[HN Gopher] Research suggests Big Bang may have taken place insi...
       ___________________________________________________________________
        
       Research suggests Big Bang may have taken place inside a black hole
        
       Author : zaik
       Score  : 677 points
       Date   : 2025-06-11 19:44 UTC (1 days ago)
        
 (HTM) web link (www.port.ac.uk)
 (TXT) w3m dump (www.port.ac.uk)
        
       | thrill wrote:
       | Maybe it was the repeat.
        
       | karol wrote:
       | Beginning is an illusion created by our way of perception. Time
       | is neither linear nor real so how can there be a "beginning"?
        
         | gjsman-1000 wrote:
         | "Your honor, I could not have possibly shot that person,
         | because yesterday might not have been before today, or at
         | least, there is reasonable doubt that yesterday was before
         | today, according to some physicists on crack. I treat those
         | physicists with high regard personally though, and they have
         | degrees that you don't have, so the court must reasonably
         | conclude their opinions should be entertained."
        
           | asveikau wrote:
           | I guess that's a joke, but it's actually kind of serious that
           | causality, personhood, identity, free will, etc. are all
           | social constructs.
           | 
           | They are _useful_ to us, but every now and then it 's helpful
           | and humbling to remember it's a fiction we assign, rather
           | than fundamental.
           | 
           | Criminal justice or the concept of culpability is one of
           | these areas. I know I've seen material by Robert Sapolsky, a
           | neuroscientist who does not believe in free will, talking
           | about how off the mark criminal justice and punishment for
           | crimes can be.
        
             | ofjcihen wrote:
             | You're stating this as if determinism has been proven
             | beyond a doubt which is not the case.
        
               | asveikau wrote:
               | I think it's unclear what kind of determinism you are
               | presuming. Determinism in the universe? Determinism in
               | consciousness? Certainly a deterministic machine can
               | exist in a non-deterministic universe.
               | 
               | However I didn't just assume a lack of free will. I also
               | assumed a lack of _identity_. Do you realize that _who
               | you are_ is socially defined? When you breathe in, the
               | air in the room around you becomes part of you. When you
               | breathe out, you lose certain gases. When you eat your
               | food, similar story. There 's a good case to be made that
               | "you" are in the entire room or the entire food chain.
               | That does make causality and culpability hard to assess
               | objectively. When we do so, we do so subjectively.
        
               | ofjcihen wrote:
               | Ah, so we're playing at being shamans.
               | 
               | In that case I dub you a mushroom.
        
               | asveikau wrote:
               | Don't be silly. I didn't say anything about shamans. I'm
               | saying human existence is subjective. Culpability, like
               | the courtroom joke above, is subjective. They're useful
               | models for how the world works but it isn't objective
               | reality.
               | 
               | We would do well to remember that every now and then.
               | People who get too into pretending their perspective is
               | objective reality tend to do stupid things.
        
               | rendx wrote:
               | Isn't identity exactly defined as what one perceives as
               | part of oneself? Food becomes me as soon as I dis-member
               | it to make it to be part of myself. Other food becomes
               | you. This doesn't make food not within my sphere of
               | perception a part of me; before digestion, it stays
               | separate, like a virus doesn't become part of me -- the
               | immune system acts a biological discriminator between
               | what is part of me, and what is not. You are not me, and
               | I am not you; we are physically attached to different
               | matter. I understand people play mind games based on
               | varying definitions of identity, but ultimately you will
               | find that you have control over certain things comprised
               | of physical matter, which then together with your mind
               | makes up "you", and you're not in control of other
               | things, which make them "not you". That's how I would say
               | it is defined, after all. I am not in the entire food
               | chain, because my perception and control simply doesn't
               | reach that far. If I could control objects with my mind,
               | it would be reasonable to say that they are a part of "my
               | body", which makes them a part of me. If you use these
               | language constructs differently, we lose the ability to
               | communicate over them?
        
               | asveikau wrote:
               | Seems like a long-winded way to say you suffer from
               | anxiety.
               | 
               | > like a virus doesn't become part of me -- the immune
               | system acts a biological discriminator between what is
               | part of me, and what is not
               | 
               | But what about symbiotic organisms? What about your
               | microbiome? Or the mitochondria, which began its
               | existence as a separate organism? Or, they say our DNA
               | includes many viruses that our ancestors contracted. A
               | number of these things do stick with us and we sometimes
               | even become totally dependent on them to function.
        
               | rendx wrote:
               | Exactly? I agree that identity is a fuzzy construct which
               | includes socially constructed elements, and is not a
               | fundamental "thing" that can be observed externally and
               | then named "identity". I disagree that it is therefore
               | "fiction"; as a concept, it is very real? My point was
               | that I don't see how you can claim that identity is
               | nonexistent ("lack of identity"), since the moment I use
               | the term, I "create" and "have" it; it is a flexible
               | enough umbrella to include the distributed system of my
               | body, since I cannot exist separately from it? What
               | "belongs to me" contributes to my identity.
               | 
               | To pick one possible simple and broad definition from WP,
               | "Identity is the set of qualities, beliefs, personality
               | traits, appearance, or expressions that characterize a
               | person or a group." -- you made it sound like that set is
               | empty, which doesn't make sense to me. My identity is
               | part of "I". Every being has an identity; it's not
               | something you can get rid of?
        
             | cwmoore wrote:
             | Let me strengthen the observation to say they are the
             | "social constructs [most] useful to [those who survive]
             | us."
        
             | layer8 wrote:
             | That doesn't affect time in the sense discussed here,
             | though, which is a fundamental dimension in our physical
             | theories.
        
               | asveikau wrote:
               | It's been several years and I'm not fresh enough to
               | summarize it, but some time ago I read Carlo Rovelli's
               | "The Order of Time" which is a pop science book on why
               | that isn't true. Ymmv. I'm sure many reading this know
               | more than I do about the topic.
        
               | layer8 wrote:
               | Carlo Rovelli's book is idiosyncratic, it doesn't reflect
               | scientific consensus on the matter.
        
               | asveikau wrote:
               | Care to give a specific example?
        
               | layer8 wrote:
               | It's more a philosophical book than a physics book. I've
               | only skimmed it, but it presents philosophical views that
               | don't reflect a scientific consensus.
        
             | exe34 wrote:
             | An interesting corner of philosophy for me is when people
             | worry about perfect clones with all your memories. The only
             | reason it bothers us is because we're not used to our
             | doppelgangers turning up and claiming our sofas and
             | relationships. In a polity where clones are commonplace and
             | provision is made to inform the source and the perfect copy
             | that their material possess will be divided or some stuff
             | will be provided, the shock value would fade away.
        
           | emigre wrote:
           | "Objection, your honor. In the many-worlds interpretation
           | there is a world in which that happened."
        
             | lazide wrote:
             | I wonder how far counsel could take it before the judge hit
             | them with contempt for lawyering while Nietzsche.
        
             | layer8 wrote:
             | Many-worlds doesn't predict that everything happens
             | somewhere; far from it.
        
               | emigre wrote:
               | Well, it's just a joke. :) It doesn't necessarily have to
               | make a lot of sense.
               | 
               | In any case, I find your comment very interesting. I'm
               | studying quantum computing at the moment, and I've had to
               | read the different interpretations of quantum mechanics,
               | including Everett's many-worlds interpretation. As a non-
               | physicist, I've found the different interpretations
               | fascinating.
               | 
               | The many-worlds one, as far as I understood it, says that
               | all the possible outcomes of a quantum measurement
               | actually "happen" in different worlds. I have the
               | impression that you would be able to give a much better
               | explanation.
               | 
               | In any case, in the joke the gun is shot in the macro
               | world, not in a quantum state. It's possible that it is a
               | quantum gun, but probably not.
               | 
               | Let's say "overruled" then.
        
               | layer8 wrote:
               | The many-worlds theory says that the time-evolution of
               | the (universal) wave function according to the
               | Schrodinger equation is what's real. Different "slices"
               | ("branches") of the wave function correspond to different
               | "worlds". (A "world" is basically defined by what is
               | quantum-entangled together.) The wave function thus
               | decomposes into the different worlds.
               | 
               | Collapse theories, in contrast, state that at specific
               | points in time (the "measurements"), the wave function
               | stops following the Schrodinger equation, and instead
               | collapses to a single slice/branch/world, thus upending
               | the natural proliferation of branches implied by the
               | normal time-evolution of the wave function according to
               | the Schrodinger equation.
               | 
               | Even in many-worlds, however, the wave function doesn't
               | necessarily contain all conceivable worlds. It only
               | contains the worlds, following from some initial quantum
               | state, that follow from the Schrodinger equation. While
               | it's true that all possible outcomes of a quantum
               | measurement become real (because they are all contained
               | in the wave function in superposition), "possible" here
               | means specifically what the equations allow, not any
               | imaginable world.
        
               | emigre wrote:
               | Thank you for the explanation! Your comment has helped me
               | with my Master's degree. The magic of Hacker News!...
        
         | 90s_dev wrote:
         | xkcd super soaker
        
       | jjallen wrote:
       | What if it wasn't the beginning of _our_ universe or wasn 't the
       | beginning of everything, including what is probably outside of
       | our universe?
        
         | colechristensen wrote:
         | Eh, the thing about the statement there is you're redefining
         | "universe", which is fine, but restating a definition isn't
         | really saying anything new. The literal meaning of "universe"
         | especially with respect to the Latin origins is... well...
         | everything. It may make sense for physics to separate in to
         | separate sets of everything if there's some reasonable
         | justification.
        
           | exe34 wrote:
           | There's the Universe (everything everywhere everywhen), and
           | then there's the observable universe. Most testable theories
           | will be referring to the observable universe.
        
         | runarberg wrote:
         | As I understand it (I'm not a cosmologist by any means), saying
         | that the observable universe began at big bang simply means
         | that anything that happened before the big bang has no effect
         | on what happens afterwards.
         | 
         | There may be other universes out there, with their own big
         | bangs, but that has no effect on ours.
         | 
         | Reading this article, I think they are simply disputing the
         | necessity of singularity inside a black hole, and hypothesize a
         | universe which expands from non-singularity black hole, while
         | staying inside its own event-horizon.
         | 
         | That is how I understood it at least, somebody please correct
         | me if I misunderstood it.
        
       | DannyPage wrote:
       | Asimov already covered this in The Last Question:
       | https://users.ece.cmu.edu/~gamvrosi/thelastq.html
        
         | JdeBP wrote:
         | Not really. Asimov's story did not represent the process as a
         | mathematically inevitable consequence of physics. It might not
         | even have gone through a second cycle. Cellular life, dollars,
         | and teletypes would all have had to come about again. (-:
        
       | xorokongo wrote:
       | "Nothing" implies that something exists, this duality creates the
       | universe.
        
         | aswanson wrote:
         | There is no proof of "nothing " existing. Every observation we
         | take, we see "something".
        
           | xorokongo wrote:
           | Than why do we need a beginning if there was always
           | something.
        
             | roywiggins wrote:
             | There is as yet no proof that there was nothing before the
             | big bang, it's just a supposition. The hot dense universe
             | definitely happened but whether that was the "beginning" is
             | essentially unknown.
        
             | lazide wrote:
             | For the same reason the mind seeks for an ending if there
             | is something. It's the environment our little neural nets
             | trained in.
        
             | thesuitonym wrote:
             | We don't. There was never nothing, because there is no
             | "before" the big bang. Time as we know it did not exist
             | until the big bang. It's not there was nothing, it's that
             | there was no there or then.
        
             | ramon156 wrote:
             | We don't need it, the same way we don't "need" scientific
             | proof about anything. We could live our whole life pleasing
             | the stakeholders and be happy about it
        
             | johnea wrote:
             | My lay interpretation of this theory is that it says there
             | was no beginning.
             | 
             | But a cycling of a previous universe.
             | 
             | I was a little unclear on the ending, where he says this
             | theory would place our entire universe "inside" a black
             | hole of a parent universe.
             | 
             | All in all, it does seem to tie up some loose ends, and
             | suggest some order to what previously required speculation.
        
             | coliveira wrote:
             | "beginning" is a misnomer, since time itself started with
             | the Big Bang. There is no such thing as "before" the
             | singularity, as time and space were curved together.
        
               | xorokongo wrote:
               | Time is a map of the states of consciousness, I believe
               | consciousness/awareness of the universe has no beginning
               | just infinite layers of abstraction.
        
               | mrguyorama wrote:
               | This is meaningless technobabble.
        
               | daedrdev wrote:
               | I'm happy you feel that way
        
               | EasyMark wrote:
               | There are many theories that portray time as existing
               | before the big bang.
        
               | coliveira wrote:
               | Well, do the calculations of how long it takes for all
               | mass to move around in the initial moments of the big
               | bang. You'll realize that the closer one gets to the
               | singularity, the slower time passes due to time dilation,
               | which means that you'll get the whole eternity to reach
               | the singularity. It only looks like a few seconds from
               | our point of view, looking at the big bang.
        
             | Kranar wrote:
             | Strictly speaking, modern cosmology does not treat the Big
             | Bang as the beginning of all of existence, it's what
             | happens when you take observations about large scale
             | cosmology and run them backwards in time.
             | 
             | Based on the information we have available about our
             | universe, we can't make predictions or formally model
             | anything prior to a certain point in time, consequently
             | it's convenient to treat this moment as the earliest point
             | in time in which physics as we know it makes any sense. So
             | while there may have been some kind of existence prior to
             | the Big Bang, we have no way to make sense of it even at a
             | conceptual level. Given that, we may as well treat this
             | special point in time as the beginning of the universe as
             | we understand it and can explain it using physics, as
             | opposed to some absolute beginning of all of existence.
        
               | xorokongo wrote:
               | Thank you for your insightful response.
        
         | mensetmanusman wrote:
         | That's a boring axiom.
        
         | dist-epoch wrote:
         | Only if something exists. But both nothing and something could
         | not exist, and then there is no duality, just nothingness
         | without a something to relate it too.
        
           | xorokongo wrote:
           | The concept of Nothing can only exist if Something exists,
           | they both exist and are the substance that make up the
           | universe.
        
         | moomoo11 wrote:
         | Nothing is everything
        
           | kgwxd wrote:
           | Everything is everything
        
       | mrtksn wrote:
       | Isn't time a human invention useful to model the nature? It's
       | literally just a defined interaction as a reference, i.e. the sun
       | rising up and going down which is the rotation of the earth.
       | 
       | So IRL there's no time, there's no need to have a beginning or an
       | end. Whatever happened when all the matter was close together
       | isn't the beginning of anything, just a phase.
        
         | tomrod wrote:
         | I'm butchering the mythology, but the Greeks had Cronos and
         | Kranus. One was measurement, and one best explained as cause
         | and effect.
        
         | soulofmischief wrote:
         | We have no idea if there is a meaningful beginning or end,
         | other than heat death. But time is real in the sense that there
         | is an arrow of time, due to entropy.
        
         | Morizero wrote:
         | Not true. The arrow of entropy has a direction and it's the
         | same as the arrow of time. There's not a good explanation for
         | why though.
        
           | mrtksn wrote:
           | There's no arrow of entropy, it's an invented useful model to
           | describe something that nature does. Everything is like that,
           | I.e. there's no electric field, it's a useful way to do
           | calculations about particle interactions.
        
             | lagrange77 wrote:
             | Of course these are models. And to be able to recognise
             | that entropy increases with time is an example for their
             | usefulness.
        
               | mrtksn wrote:
               | Does it increase over time or does it do its thing and in
               | our model we decided that stages of it is called time?
        
               | lagrange77 wrote:
               | Right, i had the same thought. What we can say is, that
               | the quantities we call t and S are correlated.
        
               | Morizero wrote:
               | Absolute entropy of a system is calculated either by
               | integrating heat capacity/temp at constant pressure from
               | 0kelvin to the measured temperature, or by calculating
               | via Shannon's method using average amount of information
               | in a discrete random variable.
               | 
               | There is no time factor in any absolute entropy equation.
               | 
               | Empirically, if you measure the entropy of a closed
               | system at a given time, and you measure the entropy of
               | that same closed system at a different time, then
               | calculate the deltas of each, their signs match so long
               | as the time delta is finite and the system isn't empty.
               | So stated plainly, as time increases, so does entropy.
               | 
               | By combining these first principle formulae with the
               | empirical results on entropy, you arrive at the second
               | law of thermodynamics. However, like I said before, we're
               | not really sure why the signs match and it's considered
               | to be an unsolved problem in physics.
               | 
               | https://en.wikipedia.org/wiki/List_of_unsolved_problems_i
               | n_p...
        
           | Kranar wrote:
           | There's a perfectly good explanation for why though, in fact
           | the explanation is what motivated the formalism of entropy to
           | begin with. There are significantly more ways that the energy
           | contained within a closed system can spread throughout that
           | system than there are ways for energy contained within a
           | closed system to condense, so that if you observe the state
           | of a system at two different moments in time, you will expect
           | to see it evolve towards the statistically more likely
           | outcome than the statistically less likely outcome.
           | 
           | And from first principles, that's what entropy is, a measure
           | of how energy is dispersed throughout a system. Of course
           | once you have that first principle understanding of entropy
           | then you can come up with more rigorous formalisms to
           | properly quantify what it means for energy to be distributed
           | throughout a system, such as measuring the number of
           | microstates that correspond to a macrostate, and other
           | various formalisms that are more or less equal to each
           | other... but fundamentally they all start from this basic
           | principle.
        
           | majoe wrote:
           | If time were running against the arrow of entropy, nobody
           | could perceive or measure it, right? Remembering something is
           | per se an increase in entropy, so the universe could run in
           | negative time direction, but we would simply forget, what had
           | happened.
           | 
           | That said, I personally think such thought experiments are
           | futile and the nature of time has to be understood by its
           | connection to causality and information.
        
             | Kranar wrote:
             | Of course you could perceive it, measure it and record it.
             | The entropy of your body or your brain is not necessarily
             | increasing, nor is the entropy of your computer or other
             | information storage systems.
             | 
             | Entropy only statistically tends towards an increase in
             | closed systems and neither your computer or your brain are
             | closed systems. They are both constantly getting energy
             | from an external source of power and in turn dispersing
             | previously consumed energy out into their environment.
             | 
             | And yet you still manage to perceive things just fine... in
             | fact your perception of the world is unlikely to change
             | whether or not the entropy in your brain increases or
             | decreases by some bounded amount (of course too much of
             | either an increase or decrease will destroy your brain).
             | 
             | Your claim about remembering an event, which likely alludes
             | to Laplace's demon [1], requires an overall increase in
             | entropy in the system as a whole, but does not require an
             | increase in entropy in the specific part of the system that
             | is recording the event.
             | 
             | Every time your computer calls a function like memset(dst,
             | 0), or sorts a list, or arranges data into some kind of
             | structured binary tree, your computer is decreasing its own
             | internal entropy by taking a statistically likely
             | arrangement of bits and transforming it into a very
             | unlikely arrangement of bits. The decrease in the internal
             | entropy of your computer is more than offset by an increase
             | in global entropy but that global entropy is radiating way
             | out into the cosmos and has no impact on your computer's
             | ability to register information.
             | 
             | [1] https://en.wikipedia.org/wiki/Laplace%27s_demon
        
         | mensetmanusman wrote:
         | No, time is what the clock measures. Consciousness does not
         | collapse the wave function meaning clocks exists without humans
         | and time exists without humans.
        
           | lazide wrote:
           | The second, however, is a purely human invention.
        
           | mrtksn wrote:
           | Exactly, time is whatever the clock measures and the clock
           | does it through some defined physical interaction. Can be a
           | swing of a pendulum, can be vibration of an atom, flow of
           | sand, unwinding of a spring etc.
           | 
           | It's useful because its quantifiable.
        
         | roywiggins wrote:
         | The hot dense universe caused our current cool universe, and
         | not the other way around, which makes the two states of the
         | universe quite different.
        
         | meindnoch wrote:
         | Time is the coordinate of spacetime that has a different sign
         | in the metric than the other three.
        
         | 90s_dev wrote:
         | Try writing a computer program that has side effects without
         | time existing.
        
       | lloeki wrote:
       | This has been one of my pet theories for a while.
       | 
       | https://news.ycombinator.com/item?id=39271752
        
         | xutopia wrote:
         | I love that theory. I very much spent time thinking that it
         | would be cool if we were inside a black hold after reading A
         | Brief History of Time.
        
       | paxys wrote:
       | There are countless versions of this theory out there. Basically,
       | a universe existed, then collapsed down to a single point, and
       | then expanded again (the big bang). Rinse and repeat.
        
         | tomrod wrote:
         | Or a universe expanded inside a black hole and we are holograms
         | on the shell.
        
         | Antipode wrote:
         | In this version we're still inside the black hole.
        
         | wa2flq wrote:
         | "Tau Zero" by Poul Anderson
         | 
         | Is it the same universal every time? If so, see you later
         | alligator.
        
       | carbocation wrote:
       | I think it's neat that this summary is written by an author of
       | the scientific manuscript. Oversimplification is a risk, but this
       | approach eliminates the possibility that the writer did not
       | understand the underlying science.
        
         | n2d4 wrote:
         | Yea, and it was a great read too. I wish more researchers would
         | publish blog posts alongside their technical whitepapers,
         | although I acknowledge that not everyone involved in science
         | has or wishes to acquire the skills needed to write blog-form
         | content.
         | 
         | (I'd also be worried about a world where researchers are
         | evaluated based on the virality of their blog posts, vs. how
         | impactful their work was.)
        
           | pkaodev wrote:
           | Be worried then because that is the reality of the vast vast
           | vast vast vast vast vast majority of research. At this point
           | academia is a massive lumbering beast that exists and must be
           | fed because it's become a big part of the economy. Most
           | research being produced isn't really research, just people
           | keeping busy.
        
             | 4ndrewl wrote:
             | Can you cite your sources please?
        
               | johnisgood wrote:
               | Most jobs are really not important either, they just keep
               | people busy. Do you need sources for this claim, too?
        
               | lukas099 wrote:
               | Yes. Who are these people paying for jobs that don't do
               | anything, and why are they more concerned about "keeping
               | people busy" than their own profits?
        
               | ckdot wrote:
               | I'm not the one you were referring to, but I have similar
               | experiences. I'm living in Germany, and most bigger
               | companies here have such issues. I also worked for
               | companies in Netherlands and Island, so I assume it's an
               | European, if not global problem. No one is concerned
               | about keeping people busy. It's a systemic problem. And
               | there are multiple reasons for it. One reason is that the
               | bigger a company grows, the more hierarchy is necessary.
               | But increasing hierarchy will lead to people doing the
               | work are not the people that are most responsible for it.
               | So we have people that should do the work but they aren't
               | too motivated because they are not responsible enough -
               | they are too low in hierarchy level. And we have people
               | that are responsible but don't do the work. They
               | delegate. If something goes wrong or takes too long, they
               | will have enough time and skill to find an excuse.
               | Another issue is that you need more people to get
               | specific things done. At some point in time these things
               | have been done, and you actually don't need the amount of
               | people anymore. But you can't quit them because of
               | worker's laws. You maybe even don't want to quit them
               | because you think you still need them. People, of course,
               | tend to find reasons why their own work is important. And
               | they will communicate that. And the chance is good you'll
               | believe that and don't question it enough. There are more
               | reasons for that. But it's a fact that in many, many
               | companies the economical results of a lot of employees is
               | almost zero. If you don't believe this, just google the
               | biggest companies in Germany, pick one, apply for an
               | office job and start to work there. It won't take a month
               | until you'll find out. Btw. I don't want to criticize the
               | situation too much. Probably it's good that people are
               | employed, even if they don't work efficiently. Otherwise
               | the unemployment rate would be much higher. Then again,
               | Germany's economy is flatlining and a crash is not
               | unlikely.
        
               | wizzwizz4 wrote:
               | Sounds like you're describing the principal-agent
               | problem. https://en.wikipedia.org/wiki/Principal-
               | agent_problem
        
               | HeyLaughingBoy wrote:
               | > But you can't quit them because of worker's laws
               | 
               | This is generally not a problem in the US.
        
               | wizzwizz4 wrote:
               | Why do you think profits are important?
        
               | amanaplanacanal wrote:
               | I would think that profits are important to investors,
               | since that's why they invest in the first place. Maybe
               | not though.
        
               | wizzwizz4 wrote:
               | The original claim was "Most jobs are really not
               | important either, they just keep people busy." Causing
               | numbers to change on a balance sheet is not important,
               | unless that corresponds to actual worthwhile work - in
               | which case, the worthwhile work is what matters, and the
               | balance sheet is just an artefact of accounting for it.
        
               | LPisGood wrote:
               | The people doing the hiring are typically not the people
               | concerned about profits at medium and large sized
               | companies. Sure someone has to approve the headcount
               | numbers, but realistically this is an extremely flawed
               | process.
        
               | leereeves wrote:
               | Most people involved like hiring more people.
               | 
               | Workers generally like jobs where the workload is low.
               | Managers gain status by having bigger teams, whether they
               | need the extra people or not. Even investors often prefer
               | hiring (a sign of growth) to layoffs, and executives are
               | mostly concerned with pleasing investors.
               | 
               | Even well run tech companies with money to burn hired
               | more people than they needed.
        
               | chucksmash wrote:
               | It's like saying "if you know half of your advertising
               | dollars are wasted, why don't you just cut your ad buy in
               | half?"
               | 
               | I still remember the joke from my first job:
               | 
               | Q: How many people work at this office?
               | 
               | A: About half.
        
               | fc417fc802 wrote:
               | An apt analogy. Circling back to scientific research, I'm
               | sure an investigator would be more than happy not to
               | spend the time, effort, and grant money on a project that
               | wasn't going to produce worthwhile results. If only we
               | could know in advance without doing the work.
               | 
               | That does not, of course, mean that "most research being
               | produced isn't really research, just people keeping busy"
               | or whatever other nonsense an uninformed outsider feels
               | like spewing.
        
               | itsoktocry wrote:
               | Companies can lay off thousands of employees and not have
               | it affect growth, profits or, really, the workload of
               | remaining employees. How could that be possible if
               | everyone's work is so crucial?
        
               | daedrdev wrote:
               | The Bullshit Jobs jobs theory has been widely discredited
               | by researchers, but you probably won't believe them.
               | Consider that most business is B2B so it makes sense that
               | the casual observer would not know what it's for.
               | Additionally, the Bullshit Jobs book relies on a magazine
               | survey, actual studies shows that the percent of people
               | who consider their jobs meaningless is very low and also
               | decreasing over time
        
               | dguest wrote:
               | I think you're right, but it's not how I remember it for
               | some reason.
               | 
               | I didn't read the book "Bullshit Jobs" [1] as an attempt
               | to quantify how many jobs were bullshit. The author was
               | an anthropologist with no interest in quantifying the
               | economic impact. It's lots of amusing anecdotes from
               | frustrated workers and a nudge for people to question the
               | efficiency of capitalism.
               | 
               | At least that's how I read it. But reading the wikipedia
               | page it sounds like a lot of people fixated on the idea
               | that society could double its efficiency. Hard to know if
               | there's a correct interpretation of the book's claims,
               | and unfortunately we can't ask: the author David Graeber
               | died in 2020.
               | 
               | [1]: https://en.wikipedia.org/wiki/Bullshit_Jobs
        
               | johnisgood wrote:
               | > while he claims that 50% of jobs are useless, less than
               | 20% of workers feel that way, and those who feel their
               | jobs are useless do not correlate with whether their job
               | is useless. (Garbage collectors, janitors, and other
               | essential workers more often felt like their jobs were
               | useless than people in jobs classified by Graeber as
               | useless.)
               | 
               | Well, again, there is a huge difference between one's own
               | perception of their job being useful or not. I believe
               | garbage collectors, janitors, and nurses, are not
               | examples of useless jobs. Useless jobs are mainly in the
               | office, called "paper pushers". I mean come on, have you
               | not been to any jobs (nor heard of any) where you had to
               | pretend you were busy just to get paid? I saw plenty of
               | cases.
        
               | johnisgood wrote:
               | > the percent of people who consider their jobs
               | meaningless
               | 
               | Worth to point out that there is a huge difference
               | between people considering their jobs meaningless AND
               | their job being meaningless, though.
        
               | rcxdude wrote:
               | No, but it's a core part of the Bullshit Jobs theory,
               | that the jobs are obviously bullshit to everyone
               | involved. I would suggest that most jobs that aren't
               | particularly valuable are probably not locally recognised
               | as such (i.e. by the person or by their manager).
               | 
               | (In general I think while plenty of people are familiar
               | with varying levels of pointless effort in their jobs,
               | it's rare that a whole job consists of that, at least as
               | far as the person doing it and the person hiring for it
               | are concerned)
        
               | itsoktocry wrote:
               | > _The Bullshit Jobs jobs theory has been widely
               | discredited by researchers, but you probably won 't
               | believe them. Consider that most business is B2B so it
               | makes sense that the casual observer would not know what
               | it's for._
               | 
               | I'm not sure how it's possible that anyone over the age
               | of 30 can say something like this with a straight face.
               | Have you ever worked _anywhere_? I 'd love to know how
               | the "researchers" have discredited this. I'd also love to
               | see their other papers (likely, also, bullshit).
        
               | hippari2 wrote:
               | Ever since I first read this theory, I have always been
               | wondering how credible is this. Where have you heard it
               | from ?
        
               | LPisGood wrote:
               | There have been countless academics who have discussed
               | this topic, occasionally not behind closed doors.
               | Regardless, it's certainly my observation as well.
        
               | fc417fc802 wrote:
               | Countless academics have leveled targeted criticisms at
               | various practices and gone on to back those up. They are
               | targeted, actionable objections; not vague blanket
               | dismissals.
        
               | NL807 wrote:
               | Sabine Hossenfelder has a few comments on this topic in
               | her YT channel.
        
               | refulgentis wrote:
               | Sabine Hossenfelder cast herself out from academia and
               | took a recent turn to monetizing laundering peoples vague
               | understanding string theory is a waste of time (cannot be
               | proven empirically) into academia is doing fake work and
               | if they'd apologize and own up to it, maybe we would
               | trust them again.
               | 
               | Most famously, through a bizarrely written letter from an
               | anonymous whistleblower pleading that she not topple the
               | academy, as it would ruin the lives of thousands of
               | academics making up things to get grant money to survive.
        
               | adwn wrote:
               | I can't parse either of your sentences. Maybe you could
               | introduce some intermediate variables, or use parentheses
               | to give them structure?
        
               | refulgentis wrote:
               | I can't parse what you're asking for :|
               | 
               | Ran my comment + your reply through AI and asked it to
               | respond to you, as I do want to help. Let me know if
               | there's other instructions I can give it, it may have
               | taken your variable ask too literally? :(
               | 
               | Here's its output:
               | 
               | Sabine Hossenfelder, after distancing herself from
               | academia, has recently pivoted to monetizing a specific
               | narrative: Let's define Premise A as "String theory is a
               | waste of time because it cannot be empirically proven."
               | 
               | She generalizes from Premise A to a broader Claim B:
               | "Academia, more broadly, is producing fake work."
               | 
               | Her argument seems to imply that:
               | 
               | If academia were to publicly acknowledge this, or
               | apologize for promoting unverifiable theories, then the
               | public might begin to trust it again.
               | 
               | This general thrust reached a kind of crescendo in one of
               | her more notorious moments: -- An oddly written letter,
               | allegedly from a whistleblower within academia,
               | essentially begging her not to "bring down the system."
               | The letter's rationale? That dismantling the status quo
               | would destroy the livelihoods of thousands of academics
               | who, according to the letter, are fabricating just enough
               | plausible-sounding work to secure grants and stay afloat.
        
               | nwienert wrote:
               | Pretty valuable to have people who see A to be true, have
               | presumably seen some of B to be true too (trivial to see
               | with the many replication crises) - and then to do their
               | best to disseminate that to the general public so change
               | can be made. I see no problem there, and I'd hate for the
               | case where people were afraid to make content covering it
               | because they were waiting for years for huge studies
               | (which could also be poorly done) to 'prove' it.
        
               | lynx97 wrote:
               | Hossenfelder feels like a fraud. She likely is.
        
               | jandrese wrote:
               | Sabine is an asshole. Doesn't mean she is wrong, and I
               | appreciate when she reads some paper that has made a
               | bunch of headlines to figure out if they're full of crap
               | or not (spoiler alert: the answer is usually yes), but
               | while she can identify the problem she's not part of the
               | solution. Her divorce from academia means she has little
               | power to affect change for the better given how the
               | incentives are currently aligned. She can make a lot of
               | noise, but the people actually pulling the levers have
               | rigged the system in their favor enough to not care.
        
               | NL807 wrote:
               | So she is an arsehole for exposing bullshit? I don't see
               | the problem. I think people take issue with her because
               | of her confrontational persona.
               | 
               | >while she can identify the problem she's not part of the
               | solution
               | 
               | Does she have to be, in principle?
               | 
               | > Her divorce from academia means she has little power to
               | affect change for the better given how the incentives are
               | currently aligned.
               | 
               | Wouldn't be so sure about that. She is getting more
               | public exposure than most academic would in their
               | lifetime. More importantly, exposure to audience
               | _outside_ of academia. Voters. Her effort in creating
               | public awareness has certainly stirred the nest in some
               | academic circles.
        
             | tracerbulletx wrote:
             | This is a good thing. This is where the economy surplus
             | went. Not to 5 days of leisure for everyone. But to jobs
             | that keep us occupied, engaged, and motivated but aren't
             | strictly required. The alternative is just either starving
             | everyone to death, except for a few elite and their slaves,
             | or everyone being bored out of their minds and wondering
             | what the point of life is.
        
               | inimino wrote:
               | If the solution is ever more manuscripts that solve no
               | interesting problems and that nobody will ever read,
               | let's find another solution.
        
               | hyperhello wrote:
               | Why would you assume someone would write the paper at
               | all, if the problem was uninteresting?
        
               | friendzis wrote:
               | That's literally the basis of employment. People write
               | papers, they get paid. Science does not get done.
        
               | inimino wrote:
               | For one thing, because I watch the AI and ML categories
               | on arxiv.org.
        
               | superb_dev wrote:
               | Is this a joke or so wildly out of touch? Both of your
               | alternatives sounds very much like the world today, but
               | we're all still working anyways
        
             | bdbenton wrote:
             | It's a controversial observation, but it is very true. I
             | work with AI models and have to read recently published
             | research to work with the latest developments in the field.
             | 
             | Do a quick keyword search on papers related to the subject.
             | So much of it is completely useless. It is clearly written
             | to keep people busy, earn credentials, boost credibility.
             | Papers on the most superfluous and tangential subjects just
             | to have a paper to publish.
             | 
             | Very little of it is actually working with the meat of the
             | matter: The core logic and mathematics. It is trend
             | following and busywork. Your sentiment is controversial
             | because people are religiously loyal to the intellectual
             | authorities of these credentialed systems, but a lot of
             | published research does not push any boundaries or discover
             | anything new. This paper seems to be an exception.
             | 
             | I would argue that a lot of the research published in the
             | social sciences also falls under this category. It is there
             | so that someone has a job. I'm not discrediting social
             | sciences in general, am just pointing out that there is a
             | lot of ways to creatively take advantage of academia to
             | secure a paycheck and this is certainly exploited. The
             | kneejerk reaction to reasonable criticism just proves this
             | point even further.
        
           | graemep wrote:
           | I think the benefits greatly outweigh any dangers. I far
           | prefer to read something like this than something written up
           | by a journalist.
           | 
           | > I acknowledge that not everyone involved in science has or
           | wishes to acquire the skills needed to write blog-form
           | content.
           | 
           | They should. If your research is publicly funded you should
           | make it as available to be public as possible. Academics
           | should be able to communicate, and I very much doubt they are
           | unable to acquire the skills
           | 
           | > I'd also be worried about a world where researchers are
           | evaluated based on the virality of their blog posts, vs. how
           | impactful their work was
           | 
           | Given how bad the measures of impact and the distorted
           | incentives this produces I am not even sure this would even
           | be a bad thing.
           | 
           | If nothing else it improves transparency about what they are
           | doing, again with public money.
        
             | quantum_magpie wrote:
             | >They should. If your research is publicly funded you
             | should make it as available to be public as possible.
             | Academics should be able to communicate, and I very much
             | doubt they are unable to acquire the skills
             | 
             | So in addition to being:
             | 
             | -professional researchers
             | 
             | -professional teachers
             | 
             | -professional project managers
             | 
             | -professional budget specialists
             | 
             | -professional scientific writers
             | 
             | -a failed idea away from losing it all
             | 
             | They should _also_ become:
             | 
             | -professional PR managers
             | 
             | -professional popular writers
             | 
             | While still being paid (poorly) for a single job of all of
             | these.
        
               | graemep wrote:
               | They should not being doing a lot your first list, and
               | should have specialist help available for some of the
               | rest.
               | 
               | I am not suggesting they become PR managers, and the
               | writing skills I am suggesting they acquire is simply
               | that required to do things like blogging. I am not
               | suggesting they achieve the standards a professional
               | writer would have, just the ability to write clearly and
               | make the effort to do so.
               | 
               | Academics should be highly skilled people.
               | 
               | In fact a lot of the problem is not they cannot do it,
               | but of distribution. A lot of universities to have
               | academic blogs and subsites about departments and
               | individuals research. Its not anything like as visible as
               | the journalists write ups about it
        
               | Elextric wrote:
               | yes
        
               | ericmay wrote:
               | We have similar demands for folks in other professions. I
               | know software engineers who are still coding day to day
               | who also have to manage team budgets and track
               | hours/projects, write patents, write blog posts to make
               | the company look good, mentor juniors, sometimes teach
               | internally or even to external audiences, present at
               | conferences, etc.
        
               | StableAlkyne wrote:
               | Yes, in a perfect world there would be professionals
               | doing this instead of putting it all on the academic.
               | 
               | However, we live in an imperfect world. When people say
               | "should" in these contexts, they're not describing some
               | ideal way the world works. They're prescribing actions
               | that are realistic based on the current system we live
               | in.
               | 
               | The world sucks. It's more useful to work with the small
               | amount of control one has, than to do nothing because the
               | action doesn't solve a wider systemic problem.
        
           | rendaw wrote:
           | Communication skills are often missing in engineering too,
           | but I think I'd argue they should be required - all work is
           | fundamentally collaborative.
           | 
           | Being able to effectively communicate to different people on
           | your team, outside your team, managers, business people, etc
           | is not optional and more than once I've seen things get
           | stalled or turn into a mess because communication didn't
           | happen.
           | 
           | STEM is often a haven for neurodivergence but I think
           | communication skills are something that is largely learned
           | and not something that comes naturally _for everyone_. People
           | who are good at communicating spend a fair amount of effort
           | rewriting, trying different wordings, different
           | introductions, getting feedback from people, etc.
           | 
           | FWIW I see things like being able to sell a proposal,
           | managing expenses, planning, etc as optional - these are good
           | to have, but someone else can do them _if_ you can
           | communicate well, but in the end the only person who can
           | communicate what you 're thinking is you.
        
           | gms7777 wrote:
           | A few years ago, at least in my field, there was definitely a
           | trend of people at least doing twitter threads explaining the
           | key findings of their papers. It's obviously less in-depth
           | than a blog post would be, but it was still usually a far
           | more accessible version of the key ideas. Unfortunately, this
           | community has basically dissolved in the last few years due
           | to the changes in twitter and to my knowledge hasn't really
           | converged on a new home.
        
         | beloch wrote:
         | It's far preferable to having university PR people write some
         | hype piece. Where they'd spend the whole time gushing about it
         | being a world first, paradigm shifting, blah blah blah, the
         | author focuses on things that actually matter. e.g. Is it
         | testable? Yes, here's what to look for.
        
         | fracus wrote:
         | Yeah, wow. That was great. His solution seems so simple and
         | clears all the previous model's problems. I guess every black
         | hole could contain its own universe.
        
           | NKosmatos wrote:
           | Too bad the author didn't explain more the concept of the
           | "parent" universe and how our own (contracting & expanding)
           | universe got created. Nice things to read/consider/ponder
           | late at night :-)
        
             | csours wrote:
             | Unfortunately, it appears that the universe does not care
             | very much about human satisfaction. Fortunately, other
             | humans do.
        
               | ivape wrote:
               | What makes you say that? This feels like a very
               | convenient planet.
        
           | alkyon wrote:
           | I would be surprised if the size doesn't matter in this case.
           | On the one hand, tiny black holes tend to be rather short-
           | lived. On the other, I suppose some threshold mass/energy is
           | needed to generate a child universe that doesn't collapse
           | immediately.
        
           | raxxorraxor wrote:
           | Ironically that was basically the first thought many had when
           | it was clear we cannot explain what happens in the edge case
           | of a singularity. It was always "perhaps another unsiverse or
           | a way into a parallel one".
           | 
           | It still leaves a lot of questions though, especially if you
           | try to marry quantum mechanics to these makroscopic models.
           | Where did the initial black hole come from and should a
           | corresponsing anti matter black hole exist?
        
             | oreilles wrote:
             | Well that's an indsight bias if I've seen one. This is the
             | first time I ever read that the "bottom" of a black hole
             | could be a entirely new universe. If there ever "always
             | was" a common hypothesis, it was the wormhole.
        
         | torial wrote:
         | There used to be a common practice of scientists writing
         | summaries of their research for lay people. I think they viewed
         | it as their civic duty. I had a collection called the World of
         | Physics which included essays written by various scientists. I
         | originally had it in the 90s and found it again after many
         | decades. Would highly recommend.
         | 
         | https://www.amazon.com/World-Physics-Library-Literature-Anti...
        
       | bmacho wrote:
       | > The Big Bang is often described as the explosive birth of the
       | universe - a singular moment when space, time and matter sprang
       | into existence.
       | 
       | It is indeed "often described" in the media as such. However,
       | that is _not_ the currently accepted theory. "What if there were
       | no space and time before the Big Bang" is just Stephen Hawking's
       | pet theory.
        
         | twodave wrote:
         | Might as well believe in God if you're going to believe in
         | spontaneous accidental creation...
        
           | kibwen wrote:
           | Why not? If you can't observe it, test it, and reproduce it,
           | then it lies outside the realm of science and in the realm of
           | belief. Until someone figures out a way to experimentally
           | verify the big bang hypothesis (or any other explanation for
           | the origin of the universe or what came "before"), it's
           | entirely fair to attribute it to whatever you feel like, be
           | it a god or anything else. There is no law of the universe
           | that guarantees that science is capable of answering all
           | questions.
        
             | ACow_Adonis wrote:
             | Well, I think surely the entirely fair thing to do is to
             | just admit we don't know rather than make any attribution
             | or imply any possession of an answer to those questions?
        
               | kibwen wrote:
               | Certainly, that's also perfectly fair. The thing to keep
               | in mind is that some people derive utility from belief in
               | some sort of creator, so ultimately it's an argument of
               | values (specifically, you're looking to argue that people
               | should prefer uncertainty to unprovable (but also
               | undisprovable!) certainty).
        
               | tstrimple wrote:
               | Humans have created models for things they don't
               | understand throughout human history. Certainly throughout
               | any recorded history. We don't know, but we have a model
               | that fits pretty well and we can guess at the underlying
               | causes. We'll be wrong more often than right, but over
               | time as we get more data and we can test more things, we
               | get a more accurate model. Not necessarily the right
               | model. We may never get that. But based on those models,
               | "guesses" are far more reliable than "The Sun is a god
               | who circles the world".
               | 
               | While we don't "know" how gravity works we can explain it
               | and model it much more accurately now than when logos was
               | the explanation. Providing those details is far more
               | useful than a simple "we don't know."
        
             | mjh2539 wrote:
             | If you can't observe it, test it, and reproduce it, then it
             | lies outside of the realm of (natural) science and may lie
             | within the realm of mathematics, philosophy, or (gasp)
             | theology.
             | 
             | > There is no law of the universe that guarantees that
             | science is capable of answering all questions.
             | 
             | There's a name for a more nuanced version of this "law" and
             | there's a good amount of work being done arguing for and
             | against weaker and stronger versions of it:
             | https://plato.stanford.edu/entries/sufficient-reason/
        
               | kibwen wrote:
               | I think it's important to clarify that the question of
               | whether or not everything _has_ a cause is itself outside
               | of science. Science is about determining _what_ a cause
               | is likely to be, using the universe itself as a source of
               | truth, and constrained by fundamental limits on our
               | ability to observe and experiment. Which is to say, even
               | if the philosophers conclude that everything must have a
               | cause, there is still no law that says that we (as
               | scientific agents of a universe that is attempting to
               | understand itself) are capable of determining every
               | possible cause.
        
           | kgwxd wrote:
           | Belief in anything is completely trivial unless you act based
           | on those beliefs. No one is going to waste time worshiping,
           | or murder someone over, the "nothing" from before
           | "something".
        
           | arbll wrote:
           | Anything outside of what we can observe will always be based
           | on faith anyway. We'll probably never understand what's
           | "before" the big bang, wether it make sense to ask that
           | question or why something exists rather than nothing.
        
           | pharrington wrote:
           | Which God? Vishnu? Ra? Amatarasu?
        
             | ben_w wrote:
             | Prince Philip?
             | https://en.wikipedia.org/wiki/Prince_Philip_movement
        
             | hshshshshsh wrote:
             | Assume God exists.
             | 
             | Various isolated cultures are going to come up with
             | different names for God.
             | 
             | This like saying which Sun? Surya, Ra or Helios?
             | 
             | All are different names of sun. But there is only one sun.
        
               | nathan_compton wrote:
               | On the other hand, there are a lot of stars and different
               | cultures might give them different names and yet there
               | really are many of them.
               | 
               | Furthermore, assume God doesn't exist. Lots of cultures
               | might invent god for various reasons and they'd naturally
               | have different names and attributes for them, which in
               | fact seems to be the current state of affairs.
               | 
               | In fact, if we assume God exists and is actively in
               | communication with humans, its actually a bit _weird_
               | that different human cultures would have different
               | conceptions and names for that being. Why didn 't it just
               | give everyone the same name and information?
        
               | hshshshshsh wrote:
               | Why do you think God will have a name? Name is used by
               | humans to identity a person among a lot of other persons.
               | Why will God have a name if it is the only thing in
               | existence?
               | 
               | To answer the question of why humans give name to God.
               | It's to make god more relatable so that they can workshop
               | it. And use devotion to come closer with it. Look up
               | Bhakti Yoga.
        
               | yibg wrote:
               | How about just having one God vs many? If there is a
               | single omnipotent being, why do various cultures have
               | multiple gods? And why do different cultures' gods tell
               | them different things?
        
               | hshshshshsh wrote:
               | Fair question. So my understanding is God is
               | consciousness. It's omnipotent, all knowing and eternal.
               | It's the only thing which is constant in your life and it
               | sees everything you do.
               | 
               | Now, you cannot worship consciousness as humans because
               | it's invisible and you can never imagine it. You need a
               | version of consciousness that you can see as well as you
               | can relate to. So cultures invent localized version of
               | God which people can relate to. And of course it will
               | have attributes similar to that of the culture. But the
               | properties kind of still hold. Like all knowing, powerful
               | etc.
        
               | nathan_compton wrote:
               | I didn't say he'd have a name, I said he'd give humans a
               | uniform one since, according to, for instance, the
               | Christian worldview he is purported to be interested in
               | human affairs.
        
               | devnullbrain wrote:
               | But that sun has never been a pharoah of Egypt.
               | 
               | If the only common factor is a belief that 'something'
               | created 'something', you're really not saying anything
               | worth evaluating.
        
               | steve_taylor wrote:
               | > Various isolated cultures are going to come up with
               | different names for God.
               | 
               | People hate not knowing the answer to the big questions
               | so much that they'll readily accept whatever answers are
               | served up to them.
               | 
               | > This like saying which Sun? Surya, Ra or Helios?
               | 
               | The difference is that the sun is readily observed. A
               | conveniently invisible god isn't.
               | 
               | > All are different names of sun. But there is only one
               | sun.
               | 
               | And there's only one human nature, which is why it's not
               | surprising that common artefacts of human nature (e.g.
               | religion) emerged universally throughout ancient human
               | cultures.
        
               | hshshshshsh wrote:
               | Try to find who you are and you will find god.
        
           | kobalsky wrote:
           | You're confusing belief with accepting the current scientific
           | consensus.
        
           | duped wrote:
           | There's quite a big philosophical difference between "there
           | exists a point beyond which it is possible to make
           | observations" and "the universe was created by an omnipotent
           | being"
        
             | hshshshshsh wrote:
             | Am omnipotent being is a necessity for making observations.
             | A lot of religions considers consciousness as God.
        
               | nathan_compton wrote:
               | I don't see how this is. It seems eminently reasonable
               | that observation can simply be performed by sub-
               | omnipotent beings.
        
               | hshshshshsh wrote:
               | Life is one omnipotent being. It's just ego, thoughts and
               | social identity that creates the illusion of multiple
               | beings.
               | 
               | But ego and names are made up. Separation just thoughts.
               | The more life believes in thoughts it becomes divided.
               | 
               | But the waves and ocean are one.
        
               | 47282847 wrote:
               | An illusion is something that disappears when you see
               | behind it, no? How goes it for the illusion of the both
               | of us being connected but separate beings? I think at the
               | very least it would require consent of both parties to
               | merge, so as long as I don't believe it, you have to live
               | as a being separate from me, and as such it stays ,,an
               | illusion" for you that we are one; merely an idea, a
               | potential option maybe, no?
               | 
               | You can declare Life to mean the complex interplay of
               | every living organism, but I don't see how you can go as
               | far as to claim our physical and mental separateness is
               | not there at all? After all, we need boundaries between
               | ,,us" to not be utterly alone. I like to think even of
               | ,,my" body more as a federated system, like Life maybe
               | but on a smaller scale. I have some influence on it but
               | not full control. In fact, one could say the polarities
               | in the physical realm are Nature (towards separation,
               | entropy; Kaos) and Life (actively working towards one,
               | requires energy to keep matter ordered; Order).
        
               | 47282847 wrote:
               | (Alone, all-one)
               | 
               | If we merge, by definition the ,,I" and ,,you" have to
               | die; both of us stop existing. The merger creates
               | something new, a ,,we". A single entity. We can then use
               | the definition of identity to call this new we ,,I".
               | Rinse and repeat until back to being alone/all-one?
               | 
               | Do you really want to be all-one? Omnipotent, full of all
               | potentials/possibilities? I don't know. I am already
               | overwhelmed with my limited human
               | potential/possibilities/options. And I prefer to not be
               | alone. I prefer to stay separate, and keep my identity.
        
               | nathan_compton wrote:
               | I don't get it. Put all life together and its all pretty
               | obviously NOT omnipotent as far as I can tell. Every
               | living thing on earth could spontaneously have an desire
               | about the state affairs on Pluto and I don't see any
               | reason to believe anything on Pluto would change.
        
             | Terr_ wrote:
             | Verily, for all knowest that the gods live up in the sky,
             | which is forever unreachable and unobservable by any man.
        
               | hshshshshsh wrote:
               | Yes. The man can never see consciousness. Only
               | consciousness can see man.
        
           | nathan_compton wrote:
           | I don't think so - god is substantially less parsimonious.
           | But in the end, I think you're sort of using two different
           | notions of belief as if they were the same.
           | 
           | I believe (lowercase b) in all sorts of stuff, scientific and
           | otherwise, but believing in God typically indicates some kind
           | of act of faith, which is to say, ultimately, to believe in
           | something despite the absence of evidence for it and for some
           | deeper reason than can be furnished by a warrant of some
           | kind. I can believe in the spontaneous generation of the
           | universe in the lowercase b sense of the word without really
           | having anything to do at all with the latter kind of belief,
           | which I think is kind of dumb.
        
             | mjh2539 wrote:
             | Historically, in the West at least, the ability or
             | inability to reason one's way to the existence of God
             | determined whether you needed to rely on faith or not.
             | 
             | https://www.vatican.va/content/pius-
             | xii/en/encyclicals/docum...
        
               | FeteCommuniste wrote:
               | Nice, paragraph 5 and he's already into "evolution is
               | fiction and commies love it."
        
               | mjh2539 wrote:
               | You didn't read closely enough. He is condemning the
               | notion that evolution explains the origin of all things
               | (as ridiculous as that sounds...it was a kind of
               | ontological darwinism; no reasonable person holds this
               | opinion today).
        
             | skellington wrote:
             | Sort of like believing that we have free will.
        
           | zthrowaway wrote:
           | The Big Bang theory was created by a Catholic priest. So yes.
        
             | mcswell wrote:
             | And the Big Bang was created by the priest's God.
        
         | koakuma-chan wrote:
         | What is the currently accepted theory?
        
           | bmacho wrote:
           | We have no theories working at those conditions. Wiki says
           | 
           | > General relativity also predicts that the initial state of
           | the universe, at the beginning of the Big Bang, was a
           | singularity of infinite density and temperature.[6][obsolete
           | source] However, classical gravitational theories are not
           | expected to be accurate under these conditions, and a quantum
           | description is likely needed[7].
           | 
           | https://en.wikipedia.org/wiki/Gravitational_singularity
        
             | DrammBA wrote:
             | > [6][obsolete source]
             | 
             | I didn't know but apparently wikipedia treats old sources
             | as obsolete, doesn't matter if there's new information or
             | not that would make it obsolete.
             | 
             | I wonder if any sources supporting the notion that the
             | earth is round must be updated every couple of years with a
             | new source or study.
        
               | cwmoore wrote:
               | That exemplifies a much deeper problem than good
               | information, "Good Law":
               | https://en.m.wikipedia.org/wiki/Good_law
               | 
               | As an aside, the earth is almost flat, just not nearly as
               | flat as the Universe.
        
               | DrammBA wrote:
               | > As an aside, the earth is almost flat, just not nearly
               | as flat as the Universe.
               | 
               | Source? And make sure to update your response every few
               | years.
        
               | cwmoore wrote:
               | It's in the Library of Babylon. My standing citation.
        
               | mkl wrote:
               | Obsolete doesn't just mean old, it means superseded by
               | newer information.
        
               | DrammBA wrote:
               | I agree with you, wikipedia seems to disagree with both
               | of us
        
           | arbll wrote:
           | At t=0 or "before" none
        
           | joquarky wrote:
           | This is the best theory we have:
           | 
           | https://en.wikipedia.org/wiki/The_Last_Question
        
         | jerf wrote:
         | A more accurate summation would be that _our theories_ do not
         | permit us to go back beyond what appears to be the  "Big Bang",
         | and indeed, we can't quite get to it either, since the need for
         | Quantum Gravity becomes too great as we get to what seems to be
         | the "zero time". We have no principled, reasonable way to make
         | any claims about what came before the point where our theories
         | break down, and that includes the claim that there was no space
         | or time at all before then.
         | 
         | Thus, anything and everything you've heard about what is there
         | "before the big bang" has always been speculation. I mention
         | this because sometimes people read the science media, which is
         | always reporting on this speculation, and think that the
         | reporting on the speculation constitutes "science" constantly
         | changing its mind, but that's not the case here. Science has
         | consistently not had a justifiable position on this topic,
         | ever. It has always been speculation. It is the press that
         | often fails to make this clear and writes stories in terms of
         | what "science" has "discovered", but any claims of certainty in
         | this area are not the claims of "science".
        
           | _alternator_ wrote:
           | Interesting thing with this work is that it does create an
           | observable, testable hypothesis: slightly positive curvature
           | of the universe.
        
         | smadsen wrote:
         | What people seem to not be able to conceptualize, consciously
         | or not, is that there really is no "before" the Big Bang in the
         | standard model (Lambda-CDM), if time itself exists only after
         | t=0.
        
           | nathan_compton wrote:
           | The Lambda CDM does not really say that. As other commenters
           | have pointed out, Lambda-CDM is silent on the very earliest
           | few moments of the universe where quantum gravity would be
           | required.
        
         | AtlasBarfed wrote:
         | Seems inevitable that we'll discover we aren't the only
         | universe / only cycle.
         | 
         | We went from thinking the Earth was the center of the universe,
         | to the sun being the center of the universe, and the next
         | obvious step is our universe isn't at the center of universes.
        
       | mensetmanusman wrote:
       | O[?] = 0.0007 +- 0.0019 (68% confidence level)
       | 
       | If the universe is curved dark energy is still a problem because
       | the expansion is getting faster and overcomes the current
       | curvature bounds.
        
         | mclau157 wrote:
         | Expansion definitely creates some issues here, at longer time
         | scales how do we deal with this?
        
       | bglusman wrote:
       | Wow, wild this is being taken seriously now perhaps, I first
       | encountered the idea in The Life of The Cosmos ~26 years ago[0]
       | and my impression was the author, Lee Smolin, didn't REALLY
       | beleive it, but he came up with it mostly to have some kind of
       | preferable, falsifiable(er?) alternative to string theory, which
       | he disliked even more, and perhaps more as an idea of the kind of
       | theory we need to explore to start making progress... or that's
       | my memory/impression form 26 years ago, I've been meaning to re-
       | read it for a while since. Anyone read more recently/have other
       | impressions?
       | 
       | (the basic idea was fecund universes/cosmological natural
       | selection[1], such that we should expect to find ourselves, if
       | the theory were true, very near to a local maxima of values such
       | that they approximately maximize the number of black holes
       | produced... but most of the book is really taken up with a
       | fascinating look at the history of physics and ideas...)
       | 
       | [0]https://en.wikipedia.org/wiki/The_Life_of_the_Cosmos
       | [1]https://en.wikipedia.org/wiki/Cosmological_natural_selection
        
       | rramon wrote:
       | I speculate that the big bang is/was fueled by all the black
       | holes that existed and will exist, like a huge cycle where all
       | the energy sucked into black holes converges at the same point in
       | time causing the big bang.
        
         | bsenftner wrote:
         | Fractal Universe - I discussed the idea with Benoit Mandelbrot
         | back in '84 over beers, interning for him, before he'd
         | published "Beauty of Fractals."
        
           | lagrange77 wrote:
           | Cool anecdote!
        
         | jpeterson wrote:
         | How do you deal with Hawking radiation?
        
           | henry2023 wrote:
           | Maybe with space expansion? With more space, particles
           | interaction is weaker overall. So the whole system kind of
           | loses total energy.
           | 
           | * Not a physicist so this is a really uninformed take
        
           | brian-bk wrote:
           | flip the direction of time and hawking radiation ""creates""
           | mass/energy inside a black hole (overall mass/energy is
           | conserved)
        
       | collinvandyck76 wrote:
       | The bounce to me has always seemed more intuitive than the bang,
       | but man, when it comes to the quantum universe I've learned to
       | just check intuition at the door.
        
       | edfletcher_t137 wrote:
       | > The black hole universe also offers a new perspective on our
       | place in the cosmos. In this framework, our entire observable
       | universe lies inside the interior of a black hole formed in some
       | larger "parent" universe.
       | 
       | Does it also follow that black holes in _our_ universe contain
       | universes internally, beyond their event horizons?! Seems like it
       | should. Mind-blowing.
        
         | int_19h wrote:
         | It's not a new idea, although I don't think it would be
         | accurate to describe the other universes as "contained" within
         | the black hole.
         | 
         | https://en.wikipedia.org/wiki/White_hole#Big_Bang/Supermassi...
        
           | bozhark wrote:
           | Black hole to White hole to Black hole
           | 
           | It's holes all the way down
        
             | bigbuppo wrote:
             | That's a wholly a whole lot of holes.
        
         | lelag wrote:
         | Damn, I would not have guessed that Men In Black was actually a
         | documentary...
        
           | EasyMark wrote:
           | I thought the universe they were saving in that was in some
           | kind of "fish bowl" type universe (galaxy?)
        
         | goodcanadian wrote:
         | _Does it also follow that black holes in our universe contain
         | universes internally, beyond their event horizons?!_
         | 
         | Not necessarily. It's not clear that any are massive enough to
         | cross the threshold required for the "bounce."
        
       | physix wrote:
       | I think this is a great summary. It's quite intuitive and
       | elegant. Does anyone have any information about what the author's
       | peers think of this model?
       | 
       | I'd love the idea that we are living inside a black hole, which
       | is inside a black hole, which is inside a ...
        
       | m3kw9 wrote:
       | So what if one of the numerous black holes in the universe starts
       | to bounce?
        
       | RS-232 wrote:
       | Not many people these days like to hear this (I myself was one of
       | them), but the answer to this is in Genesis.
       | 
       | There's a reason some of the most famous mathematicians,
       | scientists, engineers, and philosophers of all time believe(d) in
       | God.
       | 
       | The Hebrew name of God, YHWH, literally means "He Who Is." In
       | other words, the Self-Existent One. The father and originator of
       | all things that were, are, and will be, who exists outside of
       | spacetime.
        
         | jaapbadlands wrote:
         | That explains nothing.
        
           | RS-232 wrote:
           | Neither does the precursor to the Big Bang. It's the same
           | exact thing.
        
             | jplusequalt wrote:
             | They are not the same thing. Religion and science may try
             | to answer the same questions, but they are entirely
             | different endeavors.
        
               | 90s_dev wrote:
               | The idea that they're mutually exclusive is entirely
               | stupid.
        
             | steve_adams_86 wrote:
             | The trouble is we can strive to understand the physical
             | circumstances we find ourselves in. Once we decide that the
             | circumstances simply 'just are' because He Who Is, we no
             | longer have an objective basis for discovering why things
             | are as they are. There's no need, no purpose.
        
         | SigmundA wrote:
         | This is not an answer that satisfies just begs more questions.
         | 
         | Who Created God? No one? Why does the universe need a creator
         | if God does not?
         | 
         | Where does free will and evil come from if God is "originator
         | of all things that were, are, and will be". For true free will
         | to exist it must have a source of entropy which denotes
         | something outside of Gods control and design otherwise
         | everything is deterministic as set forth by God.
        
         | BitwiseFool wrote:
         | I understand that many people yearn for a religious explanation
         | to answer the question of what caused the universe to exist. I
         | myself am content with the "it just happened" explanation, as
         | any information prior to the big bang, if it even exists, is
         | unknowable.
         | 
         | There are countless other religions that believe in a deity who
         | created the universe. These deities either created themselves,
         | or had always existed outside of space and time. To that end,
         | any one of those deities would be on equal footing with YHWH. I
         | don't think that it is appropriate to axiomatically claim that
         | a certain deity exists because only that deity could have
         | caused the universe to exist.
        
           | 90s_dev wrote:
           | Yet you call yourself a fool in your own username. Why be so
           | sure you're not wrong about any or all of those statements?
        
         | StefanBatory wrote:
         | It would be a nice argument for deism - but to jump from that
         | into anything more, seems way too extreme of a leap.
         | 
         | Why Christianity then, over Hinduism? Why _any_ human religion
         | at all?
        
           | downboots wrote:
           | The Christian answer may be "God showed the 12, martyred,
           | codified by church fathers [Wu ]" but I haven't asked any
           | Hindus, or anything nonhuman.
           | 
           | [Wu ] https://en.wikipedia.org/wiki/Trinitarianism_in_the_Chu
           | rch_F...
        
         | kgwxd wrote:
         | Yes, not many people these days like to hear senseless drivel,
         | hence the failing churches.
        
           | wolfhumble wrote:
           | Have you visited a church lately? You might like it. I for
           | sure, do!
        
             | kgwxd wrote:
             | I too like to read fiction, and play role playing games,
             | occasionally. I just don't make real-world decisions based
             | on the DM's chosen lore.
        
         | EasyMark wrote:
         | I think they mostly "believed" because they would be ostracized
         | and maybe even killed for not believing in God and saying as
         | much. Many who were famous in their lifetimes would have had
         | enemies who would have loved to destroy them via that avenue.
        
         | downboots wrote:
         | "An equation means nothing to me unless it expresses a thought
         | of God." -- Ramanujan
         | 
         | I like to think he was referring to computation. There's a
         | reality to the constant pi, its computation, and ourselves and
         | the representation being part of that same universe.
        
         | krapp wrote:
         | >There's a reason some of the most famous mathematicians,
         | scientists, engineers, and philosophers of all time believe(d)
         | in God.
         | 
         | That reason being that for much of Western history if you
         | didn't believe in God the Church would burn your research in a
         | big fire and probably you on top of it.
        
         | 90s_dev wrote:
         | You're in Athens, son.
        
       | jl6 wrote:
       | I didn't understand whether the author is implying that this
       | happens to _all_ black holes or whether the model only applies in
       | some circumstances.
       | 
       | I definitely didn't understand whether this is suggesting that
       | expanding universes can be contained within black holes that look
       | like fixed-size finite objects from the outside.
       | 
       | And what happens to the inner universe when the parent black hole
       | evaporates through Hawking radiation?
        
         | WD-42 wrote:
         | The heat death of the inner universe.
        
       | kannanvijayan wrote:
       | Oh I have so many questions on this topic.
       | 
       | I've often wondered about this. I don't have any direct physics
       | training, but it's something that felt really plausible after I
       | learned that the mass of a black hole is linearly proportional to
       | its swarzschild radius.
       | 
       | As the size of the black hole goes up, its overall density must
       | decrease. Combined with the other observation that our universe
       | has uniform density at large scales, it seemed really obvious to
       | me that there existed some threshold at which the decreasing
       | density of a very large black hole, and the fixed density of our
       | observed universe.. would cross.
       | 
       | I used to muse about this question with some other tech
       | colleagues that liked talking about physics stuff but never
       | really got a clear answer to this.
       | 
       | On a side note - I'm absolutely fascinated by the implications
       | relating to this. I'll post a follow-up thought I'm hoping
       | somebody else has also thought about:
       | 
       | I've seen discussion of dark energy mostly presented as a
       | surrogate for real energy. That there is some underlying energy
       | "accelerating things away from each other".
       | 
       | I always felt uncomfortable with that characterization. It seems
       | more reasonable to me to think of dark energy as _negative
       | energy_ - i.e. a loss of overall energy.
       | 
       | In a classical system, two things moving away from each other
       | stores potential energy that can be recouped at some later time.
       | Dark energy doesn't work this way - things accelerate away from
       | each other the further apart they are. From a global perspective,
       | it's an energy loss.
       | 
       | The energy loss pervades to the quantum world as well - photons
       | that start off high frequency arrive low-frequency.
       | 
       | It somehow feels more appropriate to me to think of dark energy
       | as energy being extracted out of the universe, in some form never
       | to return. Maybe like a black hole evaporating as observed from
       | the inside?
       | 
       | When I asked this of some people in real life, I was pointed to
       | answers that indicated that the "energy" component in dark energy
       | is normalized into the "tension" of space somehow. As I mentioned
       | before I'm not really studied in physics, but that explanation
       | felt unsatisfactory to me.
        
         | dvh wrote:
         | Plug estimated mass of universe to your schwarzschild formula
         | and be amazed how close it is to observable size of the
         | universe.
        
           | kannanvijayan wrote:
           | I tried once, but I'm not sure what terms to throw in there.
           | Visible matter, estimated dark matter.. anything else?
           | 
           | I think my estimate came out to less dense than the required
           | threshold but it was a while back now and cobbled together
           | with some queries to wolfram.
        
           | eapriv wrote:
           | This is true almost by definition, and doesn't tell us
           | anything interesting about black holes.
        
         | MichaelZuo wrote:
         | That is a very interesting idea... the equation and its
         | assumptions doesn't seem to have any exceptions so it does
         | strongly suggest our universe is a black hole, inside a black
         | hole?
        
         | nathan_compton wrote:
         | > It somehow feels more appropriate to me to think of dark
         | energy as energy being extracted out of the universe, in some
         | form never to return. Maybe like a black hole evaporating as
         | observed from the inside?
         | 
         | But in this story the black hole increases in size as matter
         | falls into the horizon and shrinks as it evaporates, so cosmic
         | expansion would be associated with more energy falling into the
         | black hole than leaving it.
        
           | kannanvijayan wrote:
           | I thought about this part. I'm not sure we can link apparent
           | size from outside the event horizon to apparent size from
           | inside.
           | 
           | Apparent distance is something that's affected by relative
           | frames of reference and the frames of reference are as
           | different as as can be in this case.
        
         | account-5 wrote:
         | There was a thread a while ago on here where the hypothesis for
         | why things are moving apart at faster rates is down to time
         | moving at different speeds due to mass.
         | 
         | So time in the void between galaxies is moving quicker than
         | time in the galaxies, but on the grand scale of the universe
         | the differences as up a lot.
         | 
         | I quite liked this theory, think is make sense, at least from
         | my very limited understanding of this stuff.
        
           | codethief wrote:
           | Aka Timescape Cosmology,
           | https://en.m.wikipedia.org/wiki/Inhomogeneous_cosmology
        
           | __turbobrew__ wrote:
           | Would make sense if our universe is a simulation. It takes
           | more compute power to simulate areas of high density so time
           | naturally flows slower there.
        
             | account-5 wrote:
             | Yeah, but also that's how time actually works too, time
             | runs slower for us on earth than say GPS satellites so
             | adjustments need calculated to sync the two. Again caveat
             | is I'm more than likely either just wrong or
             | misunderstanding it or massively oversimplifying it.
        
         | afarah1 wrote:
         | >follow-up thought I'm hoping somebody else has also thought
         | about [...] dark energy as _negative energy_ [...] Maybe like a
         | black hole evaporating
         | 
         | Another layman's thoughts: Isn't the energy theoretically lost
         | by black holes so faint it's currently undetectable? And isn't
         | the amount of dark energy theorized to be the major component
         | of the observable universe? It seems like the numbers wouldn't
         | add up?
        
           | kannanvijayan wrote:
           | I don't have enough of the background to speculate about the
           | numbers. Dark energy feels "big" if we think of it in terms
           | of the actual energy it would take to accelerate the universe
           | away from itself at the rate that we see.. but the rate that
           | we see is affected by our frame of reference, along with
           | distances and everything else.
           | 
           | I'm gonna pull out my lay understanding again. An evaporating
           | black hole, as it gets smaller, should get more dense and be
           | associated with a higher local spacetime curvature, no? The
           | effect of which would be to slow down apparent time for
           | observers within the system. Maybe that affects observed
           | distance and rates of speed at which things seem to be
           | happening when we look out into the sky?
           | 
           | Sometimes I regret not caring enough about calculus in
           | university.
        
         | codethief wrote:
         | > Combined with the other observation that our universe has
         | uniform density at large scales
         | 
         | s/has/had at the time of recombination
         | 
         | It is largely an assumption of LCDM that we can treat the
         | universe as practically homogeneous throughout its entire
         | evolution but potentially not a very well-founded at that [0,
         | 1].
         | 
         | > I always felt uncomfortable with that characterization. It
         | seems more reasonable to me to think of dark energy as
         | _negative energy_ - i.e. a loss of overall energy.
         | 
         | Your intuition is correct. If the Lambda term in the Einstein
         | field equations is moved over to the side of the energy
         | momentum tensor, it takes on the role of a negative
         | contribution (provided Lambda > 0, as observations seem to
         | indicate).
         | 
         | > In a classical system, two things moving away from each other
         | stores potential energy that can be recouped at some later
         | time. Dark energy doesn't work this way - things accelerate
         | away from each other the further apart they are. From a global
         | perspective, it's an energy loss.
         | 
         | Note that there is no global energy conservation in General
         | Relativity[2], only at a local scale[3]. Heck, you'll already
         | struggle to define what the energy _is_ of a given piece of
         | spacetime in a meaningful and generic manner[4, 5]. In other
         | words, violations of energy conservation due to spacetime
         | expanding or contracting (a strictly non-local phenomenon),
         | like in the case of the cosmic redshift, are expected and our
         | intuition from classical mechanics only takes you so far.
         | 
         | > It somehow feels more appropriate to me to think of dark
         | energy as energy being extracted out of the universe, in some
         | form never to return.
         | 
         | Dark energy aka the cosmological constant term in the Einstein
         | field equations is a constant term, as the name suggests. Yes,
         | there can be energy loss due to spacetime expanding (see above)
         | but that doesn't change the gravitational _constant_.
         | 
         | [0]: https://en.wikipedia.org/wiki/Cosmic_web
         | 
         | [1]: https://en.m.wikipedia.org/wiki/Inhomogeneous_cosmology
         | 
         | [2]: https://en.m.wikipedia.org/wiki/Conservation_of_energy
         | 
         | [3]:
         | https://en.m.wikipedia.org/wiki/Stress%E2%80%93energy_tensor
         | 
         | [4]: https://arxiv.org/abs/1510.02931
         | 
         | [5]: https://en.m.wikipedia.org/wiki/Mass_in_general_relativity
        
           | kannanvijayan wrote:
           | Interesting reading - this is the first thorough response
           | I've gotten to some of these question. Will check out the
           | reading material.
        
         | timewizard wrote:
         | > As the size of the black hole goes up, its overall density
         | must decrease.
         | 
         | The center of a black hole is infinitely dense. That's why it
         | even exists. The event horizon is not the black hole.
         | 
         | > and the fixed density of our observed universe
         | 
         | Our universe is expanding. It's density is not fixed.
         | 
         | You really want to be thinking about this in terms of entropy
         | and not matter.
        
           | DrammBA wrote:
           | > The center of a black hole is infinitely dense. That's why
           | it even exists. The event horizon is not the black hole.
           | 
           | Arguing semantics is rather boring when it's obvious you
           | understood the point he was trying to make.
           | 
           | > Our universe is expanding. It's density is not fixed.
           | 
           | None of that precludes uniform density at large scales.
        
             | daedrdev wrote:
             | I think a point they are trying to make is that the border
             | of a black hole is only to us outside observers, if you
             | yourself fell into one you wouldn't notice anything
             | specific when you crossed the boundary. The popular example
             | of hawking radiation references a border and pairs of
             | particles, however its actually only to help people
             | understand the idea of what is going on
        
               | viraptor wrote:
               | > if you yourself fell into one you wouldn't notice
               | anything specific when you crossed the boundary.
               | 
               | Wouldn't you notice that fairly suddenly everything's
               | getting brighter because all the light/radiation is
               | sucked back in?
        
               | PantaloonFlames wrote:
               | I learned recently on [a
               | video](https://youtu.be/a4vHwY0wMjs?t=246) that for very
               | large black holes , we suspect there is no difference.
               | 
               | For smaller BH, the gravity gradient is higher and it
               | would be detectable.
        
             | lutusp wrote:
             | >> Our universe is expanding. It's density is not fixed.
             | 
             | > None of that precludes uniform density at large scales.
             | 
             | According to observation, the universe is expanding. An
             | argument that it's really static at a large scale would
             | require contradicting observational evidence, but none
             | exists. A theory that requires abandoning observational
             | evidence bears a special burden, which this theory lacks.
        
               | Jensson wrote:
               | Black holes are capable of expanding, they do it by
               | eating material from outside.
        
               | lutusp wrote:
               | The universe's expansion, and a black hole's increase in
               | mass over time, are unrelated phenomena. We could have
               | one without the other. In fact, because of Hawking
               | radiation, in the far future we might see a larger
               | universe accompanied by smaller black holes.
        
           | kannanvijayan wrote:
           | Yeah I was referencing the event horizon as the most
           | meaningful measure of size.
           | 
           | And whether the density is fixed over time or not doesn't
           | affect the question. Let's take the universe at its current
           | average mass/energy density - whatever the "true" measure of
           | that is.
           | 
           | To the best of our understanding, at large scales the density
           | is uniform. So if we consider a suitably large spherical
           | volume of space within our (presumably infinite) universe..
           | that volume will have an average mass/energy content greater
           | than the threshold amount for a black hole of that apparent
           | volume (again, using the external event horizon frame).
           | 
           | So that suggested to me that either we live in a finite
           | universe, or we must be on the inside of an event horizon. It
           | seems like an unavoidable conclusion.
        
           | postalrat wrote:
           | It's a mathematical model, not reality. I don't believe
           | scientists believe an actual infinitely dense object exists
           | at the center of black holes.
        
           | lutusp wrote:
           | >> As the size of the black hole goes up, its overall density
           | must decrease.
           | 
           | > The center of a black hole is infinitely dense. That's why
           | it even exists. The event horizon is not the black hole.
           | 
           | >> and the fixed density of our observed universe
           | 
           | > Our universe is expanding. It's density is not fixed.
           | 
           | These are both correct and germane points. So why was this
           | post downvoted? Physics isn't a popularity contest, it relies
           | on evidence.
        
         | burnt-resistor wrote:
         | A black hole is really just a singularity with infinite density
         | by definition, but finite mass.
         | 
         | The size and density of the Schwarzschild volume is determined
         | only by mass (stationary, non-rotating). It's proportional to
         | the inverse square of mass. Density = 3c6/32pG3M2.
         | 
         | SMBHs have densities ~0.5 kg/m3 between thin air and water.
         | 
         | Stellar BHs are ~1e19 kg/m3 several orders of magnitude more
         | than a neutron star.
        
         | raattgift wrote:
         | I think given time at a blackboard we could walk through
         | Newton's cannon in the context of Poisson gravity, and for
         | extra credit with the cannonball inducing a perturbation of the
         | Poisson vector field. Even without the cannonball's
         | backreaction, the Poisson picture offers a nice image of the
         | gravitational potential energy at the top of the cannonball's
         | inertial (ballistic) curve. We would then consider a cosmology
         | like our own but with a recollapse: at maximum extent there is
         | some (quasi-)Newtonian notion of gravitational potential energy
         | for all the galaxies, since they are at the point where they
         | begin free-falling back into a denser configuration. It's then
         | the usual story of relating kinetic and potential energy, and
         | recognizing that the standard cosmological frame is close to
         | Newtonian by design. (We also have to stop this approach when
         | the galaxies are merging enough that radiation pressure and gas
         | ram pressure become relevant, because the errors become
         | astronomical).
         | 
         | Since we don't have a blackboard in front of us to interact
         | with, I can suggest Alan Guth's lecture notes on Newtonian
         | cosmology. (Guth is credited with discovering cosmic
         | inflation.) https://web.mit.edu/8.286/www/lecn18/ln03-euf18.pdf
         | See around eqn (3.3). You could also borrow a copy of Baumann's
         | textbook <https://www.cambridge.org/highereducation/books/cosmo
         | logy/53...> which studies the Poisson equation for various
         | spacetimes, however a static spacetime gets most of the focus.
         | 
         | A universe which expands forever, or which expands faster in
         | the later universe, makes a mess of this sort of approach to
         | calculating a gravitational potential energy. So does any
         | apparent recession velocity that's a large fraction of c
         | (inducing significant redshift, whatever the recession
         | (pseudo-)"force" might be).
         | 
         | However, the general idea is that there is a relationship
         | between the kinetic energy a receding galaxy (in a system of
         | coordinates -- a "frame" -- in which these kinematics appear)
         | and a gravitational potential energy still occurs in a non-
         | recollapsing universe. It's just that the potential energy
         | climbs forever, and you get an equivalent to gravitational time
         | dilation between galaxies at different gravitational potentials
         | (i.e., between early-universe galaxies and higher-potential
         | modern-times galaxies).
         | 
         | Accelerometers in galaxies will not show a cosmic acceleration
         | for any galaxy; they're all really close to freely-falling
         | (local galaxy-galaxy interactions are real -- collisions and
         | mergers and close-calls happen -- but wash out over
         | cosmological distances; look up "peculiar velocity" for
         | details). Therefore we can conclude that there's no real force
         | imposing acceleration on the galaxies. However that's also true
         | of a cannonball in a ballistic trajectory, including one on an
         | escape trajectory or one that enters into a stable orbit.
         | Consequently one can draw some practical comparisons between a
         | ballistic launch from Earth into deep space and galaxies
         | spreading out from an initially denser early part of an
         | expanding cosmos.
         | 
         | > Dark energy as energy being extracted out of the universe
         | 
         | No, it's just a way of thinking about whatever is driving the
         | expansion, and that doesn't dilute away with the expansion as
         | ordinary matter and radiation does. It's not even a "real"
         | energy in the sense that it is only an energy in the
         | cosmological frame, and is a frame-dependent scalar quantity,
         | whereas in the fuller theory it's just a multiplier of the
         | metric tensor. So it's the full relativistic metric doing the
         | work but we absorb some of that into cosmological coordinates
         | in the cosmological frame of reference, carving up the metric
         | tensor into a set of vectors including an expansion vector
         | identical at every point in spacetime.
         | 
         | The expansion vector can also be thought of in terms of
         | pressure: in a collapsing cosmological frame, a pressure drives
         | galaxies together into a denser configuration. The inverse of
         | pressure is tension, so in an expanding cosmological frame,
         | it's a tension that pulls galaxies apart into a sparser
         | configuration. (The reason one uses pressure or its inverse is
         | that the matter fields are idealized as a set of perfect fluids
         | at rest in the cosmological frame; each such fluid has an
         | associated density and internal pressure which evolve with the
         | expansion or contraction of the cosmos, generally becoming less
         | positive in the time-direction of expansion (i.e., in the
         | future direction in a universe like ours). Another way of
         | thinking about pressure is as a measure of isotropic inflow of
         | energy-momentum into a point; increasing pressure at a point
         | therefore increases the curvature at that point. Tension is an
         | isotropic outflow, and so positive tension is repulsive as
         | opposed to the attraction from positive pressure.)
         | 
         | > that explanation felt unsatisfactory to me
         | 
         | Hopefully the above helps a bit. Unfortunately there's only so
         | much teaching one might do in a series of HN comments, and
         | ultimately one probably is better served in developing some
         | grounding in the full Einstein Field Equations / Friedmann-
         | Lemaitre equations before thinking in quasi-Newtonian ways.
         | Going the other direction tends to lead to misunderstandings
         | and developing false intuitions when running into situations
         | where the quasi-Newtonian picture needs post-Newtonian
         | correction terms.
         | 
         | It's cool that you have all sorts of questions. You could
         | consider signing up for part time / non-business-hours courses
         | in relativity at a nearby community college or the equivalent,
         | depending on where you are, or maybe just bringing a hot lunch
         | to a lecturer there in exchange for a quick informal tutorial.
         | Anything like that is bound to get you to better answers than
         | raising comments on HN threads about astrophysics in the
         | broadest sense, as answers here are often somewhere between
         | non-standard and unreliable.
        
       | danieldrehmer wrote:
       | I sympathize with Lee Smoolin's cosmological natural selection
       | hypothesis, which would require that black holes give birth to
       | new universes within
        
         | bglusman wrote:
         | I can't beleive you and I are the only ones familiar with, and
         | that no one else referenced or responded to this connection!
         | https://news.ycombinator.com/item?id=44251438
        
           | meta-level wrote:
           | I too read the book and was just searching for anyone
           | mentioning it. Why can such an idea be called new, when
           | someone else already described it decades ago?
        
       | tehjoker wrote:
       | This was an interesting read, but I didn't understand exactly
       | what leads to the big crunch. I get the exclusion principle leads
       | to pressure, and this causes the bounce, but why would it
       | continue to accelerate and then decelerate resulting in a big
       | crunch?
       | 
       | https://journals.aps.org/prd/abstract/10.1103/PhysRevD.111.1...
        
         | chasil wrote:
         | I don't understand where the rest of the parent universe is if
         | all of the matter has emerged from the event horizon. Twisted
         | into a new dimension, perhaps?
        
           | tehjoker wrote:
           | My take away was that it's still somehow causally
           | disconnected from our universe. They make an assumption that
           | the space outside is empty and that makes the numbers
           | correspond closely with observations. Maybe there is stuff
           | there but very very far away?
        
       | meindnoch wrote:
       | I've read somewhere an article which posited that our 3D universe
       | might be inside a 4D black hole. When you cross a black hole's
       | event horizon, the radial coordinate becomes timelike, so you
       | lose one degree of spatial freedom. Movement is still possible in
       | the tangential directions however, so what you get is basically
       | an N-1 dimensional universe. So maybe our 3D universe is actually
       | matter that fell into a 4D black hole, and our 3D black holes
       | contain 2D flatland universes. And of course, the outer 4D
       | universe might be in a 5D black hole, etc.
        
         | unyttigfjelltol wrote:
         | Yes, and then there's the parlor game of guessing what familiar
         | property of our known universe is actually a spaghetified
         | fourth dimension.
         | 
         | I guessed c once. It _would_ be a constant. Maybe all the
         | constants are spaghettified remains of a superior universe.
        
           | jfengel wrote:
           | I don't think c is a good candidate, because it's not really
           | a parameter. It's just a correction factor for our mis-
           | judgment in picking different units for time and space.
           | 
           | In "natural units", we define the units so that the important
           | conversion factors (c, G, h-bar, etc) work out to exactly 1.
           | You can say that c is one light-year per year and then forget
           | about it.
           | 
           | The true parameters of the universe are the dimensionless
           | constants: the fine structure constant, proton-electron mass
           | ratio, 3+1 dimensions, etc.
        
             | throwawaymaths wrote:
             | > I don't think c is a good candidate, because it's not
             | really a parameter.
             | 
             | dont be so sure! there is no way to experimentally know if
             | c is a parameter or not. there are consistent physics
             | formulations which have variable, even anisotropic c.
             | physicists dont usually explore them (e.g. tangherlini
             | relativity) though because the math is considerably harder.
        
               | raattgift wrote:
               | _Physicists_ (and in particular the subset doing physical
               | cosmology) don 't usually explore parametrizations of c
               | because they're not clearly physical (and sometimes even
               | clearly unphysical), or alternatively don't help solve
               | astrophysical or cosmological problems.
               | 
               |  _Relativists_ sometimes like to explore things that make
               | using the Tangherlini transformations rather than the
               | Lorentz transformations look positively benign. (To be
               | clear, the Tangherlini synchronization system is clearly
               | unphysical, requiring infinite speeds. His thesis also
               | proposed using a distinguished global frame, which is not
               | really philosophically different from how the standard
               | cosmological frame is used, and seems OK because the
               | distribution of stress-energy can pick out useful systems
               | of coordinates in standard relativity. Unfortunately his
               | method frustrates and probably outright breaks
               | comparisons between inertial reference frames related by
               | a boost, which the standard cosmology does not, and it 's
               | hard to see an alternative method that preserves his
               | central ideas.)
               | 
               | But why even be stuck with 3+1d spacetime like
               | Tangherlini? He was trying to do physics. But an
               | unphysical metric signature with 47 plusses and no
               | minuses is really cool!
               | 
               | In our observed universe, FAPP, c is the same everywhere
               | after recombination, and we get that from spectral lines.
               | You have to play really weird games to preserve the
               | Lyman-alpha forest's apparent isotropy while introducing
               | spacetime (or redshift-space, here) anisotropy. Things
               | like BAOs make the problem even harder.
               | 
               | If we strip away all that pesky radiation and the
               | information its structure encodes, analysing variations
               | of c gets a lot easier. A relatively recent paper (Lewis
               | & Barnes 2021) I enjoyed considered anisotropy in the
               | one-way speed of light in an FLRW cosmology with zero
               | energy density (well, really the convenient Milne model,
               | which is also far from spatially flat). "So far, we have
               | considered two cases, where either the speed of light is
               | isotropic, or the extreme case where the anisotropic
               | speed is 1/2 in one direction, and infinite in the other.
               | The question remains whether this holds true in general
               | case, for an arbitrary k":
               | https://www.cambridge.org/core/journals/publications-of-
               | the-... (arxiv: <https://arxiv.org/abs/2012.12037>). "For
               | more general cosmological models, where the presence of
               | mass and energy results in curved space-time, the picture
               | is more complicated as there is no simple mapping of the
               | modified Lorentz transformations into the general
               | relativistic picture. We leave this discussion for a
               | future contribution."
               | 
               | Sadly there doesn't seem to be a future contribution yet,
               | at least going by published citations (<https://scholar.g
               | oogle.com/scholar?cites=2012575105829699847...>). (Of
               | those, I've put the Chamberlain paper on my to-read pile;
               | you'd appreciate how it relates to Tangherlini, "credence
               | is given to one-way infinite light-speed inward to each
               | particle in direct comparison against Einstein's
               | isotropic (c=constant) light-speed").
               | 
               | Of course there's also the excellent Magueigo 2003 VSL
               | overview <https://iopscience.iop.org/article/10.1088/0034
               | -4885/66/11/R...> copy
               | <https://cds.cern.ch/record/618057/files/0305457.pdf>
               | preprint <https://arxiv.org/abs/astro-ph/0305457>.
               | 
               | And even if you can make sense of an f(c) cosmology in
               | the early visible universe, you will get to epochs before
               | recombination and try to make sense of the later
               | universe's chemistry, which of course relates to big bang
               | light nucleosynthesis, baryogenesis and electroweak ssb.
               | How do you abolish Lorentz symmetry in those epochs? Good
               | luck!
               | 
               | (I mean, I think if you are doing physical cosmology you
               | ought not to ignore gauge theory...)
        
           | AtlasBarfed wrote:
           | I thought that's what the high dimension counts of string
           | theories were: taking constants and turning them into
           | dimensions.
           | 
           | Or is that too simplified?
        
           | jldl805 wrote:
           | Gravity, obvs.
        
         | account-5 wrote:
         | What's in a 1D black hole?
        
           | SlightlyLeftPad wrote:
           | /dev/null I presume
        
           | modderation wrote:
           | I'm guessing it'd look something like this on a 1-dimensional
           | number line:                   --- >   | > >> . << < |   <
           | ---
           | 
           | The dot in the middle would be the singularity, the pipes the
           | event horizon, and the contents would be increasingly warped
           | spacetime that may or may not exist, depending on your
           | interpretation of things.
        
         | codethief wrote:
         | > When you cross a black hole's event horizon, the radial
         | coordinate becomes timelike, so you lose one degree of spatial
         | freedom.
         | 
         | The second half is incorrect. Since the time coordinate becomes
         | spacelike in turn you'll still have 3 spatial degrees of
         | freedom. Dimensions can't just vanish if you believe that
         | spacetime is a 4D Lorentzian manifold (as physicists do).
         | 
         | Moreover, the singularity is not a place you can poke with a
         | stick, once you've entered the black hole. It lies in your
         | future, in the same way as your death.
        
           | BoiledCabbage wrote:
           | > The second half is incorrect. Since the time coordinate
           | becomes spacelike in turn you'll still have 3 spatial degrees
           | of freedom. Dimensions can't just vanish if you believe that
           | spacetime is a 4D Lorentzian manifold (as physicists do).
           | 
           | Can we say that one of the spatial dimensions (the radial
           | dimension) and the time dimension combine into a single
           | dimension? After crossing the event horizon aren't they 1:1
           | correlated?
        
             | raattgift wrote:
             | No, there's no change in dimensionality.
             | 
             | The swapping of timelike and radial dimensions are a "game"
             | frequently played with families of coordinates, including
             | Schwarzschild coordinates. One can apply any system of
             | coordinates on a physical system without changing the
             | behaviour of the physical system: coordinates are
             | unphysical. Think of navigating around in a neighbourhood:
             | you can talk about going forward a few blocks then turning
             | left, after which you go forward two more blocks; or for
             | the same journey, going "city north" a few blocks then
             | going "city west" two blocks. Here assuming that
             | (initially) "forward" is in the "city north" direction (and
             | "city north" is not necessarily exactly magnetic north nor
             | a section of a meridian of longitude). After the left turn,
             | "forward" is "city west". There's an analogue to the
             | discussion's (ab)use of Schwarzschild coordinates.
             | 
             | In Schwarzschild spacetime, without applying _any_ system
             | of coordinates, just floating in free-fall far from a black
             | hole extremizes your travel in the timelike dimension. (You
             | can do this at home: you stay put at some point on Earth
             | (whether you use GPS latitude /longitude/altitude or some
             | other system of coordinates) but your wristwatch keeps
             | ticking). Inside the black hole horizon, just floating in
             | free-fall extremizes your travel in the direction of the
             | singularity. Far from the black hole, accelerating as
             | strongly as you can in any direction takes travel from the
             | timelike dimension and puts it into one or more spatial
             | dimensions. In particular, you have the freedom to increase
             | the spacetime interval between you and the singularity.
             | Within the horizon, however strongly you accelerate the
             | spacetime interval between you and the singularity shrinks.
             | This behaviour seems to invite the use a different set of
             | coordinates applied to a patch of space around an observer
             | far from the black hole and a patch of space around an
             | observer inside the horizon. It's some human cognition
             | thing, and in the early 20th century it took decades to
             | discover systems of coordinates that work for observers far
             | from the black hole, at the horizon, and inside the
             | horizon. And even today, most people don't seem to try to
             | enhance physical intuitions by swapping among arbitrary
             | systems of coordinates (including _no_ coordinates) on a
             | single physical system like a black hole and a pair of
             | observers (one inside the horizon and one far outside the
             | black hole).
             | 
             | The Schwarzschild black hole interior is still locally
             | Lorentz-invariant everywhere (because the whole
             | Schwarzschild spacetime is a Lorentzian manifold).
             | 
             | The various _local_ interactions of the Standard Model will
             | keep working inside a black hole. In a _really tiny_ patch
             | around every point, everything behaves as if its in
             | Minkowski space (flat 4-d (3 spatial + 1 time) spacetime).
             | 
             | (That's one of the problems of quantum field theory on
             | curved spacetime: the "focusing-pressure" [for experts:
             | this is encoded in the Weyl curvature tensor; my "scare
             | quotes" take a view of this in a Raychaudhuri equation way]
             | gets so high that the unknown ultraviolet behaviour of the
             | Standard Model (a quantum field theory) becomes relevant.
             | The Weyl behaviour in Schwarzschild is that quasispherical
             | objects are strongly prolated with the long axis aligned
             | radially: a soccer ball or basketball starts looking like
             | an American or Canadian or Rugby football ball. The radial
             | stretching "spaghettifies" by ripping apart weaker bonds
             | (like intermolecular ones, and molecular ones, and ionizing
             | atoms), but the tangential squashing ("focusing") must
             | eventually generate more nuclear interactions, probably up
             | to quantum chromodynamics (QCD) energies possibly before
             | the radial stretching starts generating hadronization.
             | 
             | How this works in the Standard Model is just unknown.
             | However simpler "test" quantum field theories (fewer, or
             | even no, interactions; and often no colour-confinement-like
             | processes) raise really difficult questions.
             | 
             | Finally, back to the Standard Model as _local_ theory: how
             | does any allegedly quantum nonlocality behaviour work?
             | Local here in the sence that states can be distinguished by
             | local measurements alone. Related questions: can you
             | entangle particles deep inside a black hole? If an
             | entangled pair fall in together, how does the entanglement
             | evolve? Or obsessing black hole information people, what if
             | you throw in only one half of an entangled pair and locally
             | measure the outside half? Nobody has great answers for
             | these sorts of questions at present, and there 's no near-
             | term hope of testing any proposals in laboratories or via
             | astrophysical observation.
        
           | XorNot wrote:
           | I don't think the spacetime swap idea is particularly well
           | explained though? Like although it's sort of mathematically
           | true, my impression was that it's not like time suddenly
           | becomes a dimension you're moving in once inside the event
           | horizon, just that spacetime is acting so weird because
           | there's now a deliberate direction where one did not exist
           | before.
        
             | codethief wrote:
             | > I don't think the spacetime swap idea is particularly
             | well explained though?
             | 
             | What exactly do you mean by "spacetime swap idea"? If
             | you're saying the behavior of Schwarzschild coordinates at
             | the event horizon is not well-understood, then I disagree.
             | There is nothing particularly weird or surprising going on,
             | there's just a trapped surface[0].
             | 
             | [0]: https://en.m.wikipedia.org/wiki/Trapped_surface
        
               | raattgift wrote:
               | The problem is probably connecting an image of a tilted
               | causal cone at p near but outside a regularized r_s in
               | Schwarzschild spacetime with the idea that from p there
               | is a limited number of null geodesics escaping to the
               | asymptotically flat region, that the fraction decreases
               | with decreasing regularized r coordinate, and that from
               | p' at the trapping surface there are no such null
               | geodesics, as all non-spacelike curves (accelerated or
               | not) at any point on or interior to the trapping surface
               | terminate at the singularity. The idea that the
               | singularity inevitably lies in the future of _any_
               | observer at p ' is behind the "spacetime swap" notion.
               | 
               | Some of the problem is that Schwarzschild coordinates
               | have surprises buried in them, and what \Delta r and
               | \Delta t mean are not what most people tend to think.
               | 
               | Someone should do an ELI12 of Unruh's (ca. 2014)
               | excellent (give or take varying the spelling of Martin
               | Kruskal's surname) Schwarzschild BH global coordinates
               | pedagogic review <http://theory.physics.ubc.ca/530-21/bh-
               | coords2.pdf> and add in a bit on Fermi normal coordinates
               | as a maybe-obvious not-a-chart follow-on to the commenary
               | just above eqn (55). But on "maybe-obvious", Unruh has
               | the choice line: "Since in a large number of cases, the
               | single horizon coordinates were discovered long before
               | Schild's coordinates, this is an exercise in alternate
               | reality - what could have so easily happened if only the
               | generators of those coordinate systems had recognized
               | what they had."
        
         | twothreeone wrote:
         | What? Wouldn't that mean an object's speed in some direction
         | determines how time passes once it crossed over, and
         | conversely, it would experience its old time dimension as
         | spatial and be able to "move through (old) time" freely after
         | crossing the event horizon?? My head hurts.
        
         | mousethatroared wrote:
         | You can't have the curl operator in 4D.
        
         | paulnovacovici wrote:
         | I've always like to explore the idea of our universe being in a
         | static 5th dimension where the 5th dimension represents
         | randomness/entropy. The same way to think about exploring a 2d
         | plane in a 3 dimensional space where the 3rd dimension is
         | constant. We just happen to be in a random big bang in this 5th
         | dimensional space
        
       | molticrystal wrote:
       | If the crux of the article is the fermion bounce, and you compare
       | that to how much matter and energy we are aware of, that is quite
       | the black hole, which leads one to start wondering what
       | environment it existed in to become that size. Even if it is now
       | stuck due to a positive curvature of just bouncing back and
       | forth.
       | 
       | I would like the article to acknowledge a bit more though that
       | blackhole universe theories and speculation are quite old now,
       | not radical and a striking alternative, as it is natural to think
       | about it once you learn of the concept of event horizons. What
       | differentiates this though is the analytical solution.
        
       | pontifier wrote:
       | There was a youtube lecture I saw years ago that showed exactly
       | what you'd see as you fell into a black hole and passed through
       | the event horizon.
       | 
       | You'd see EVERYTHING that EVER crossed the event horizon. But
       | critically, you'd see it EXACTLY as it was at the monent it
       | crossed.
       | 
       | Sounds a bit crowded to me. Sounds a bit like I'd expect the big
       | bang to look.
        
         | EasyMark wrote:
         | I thought you were supposed to get spaghettified and die
         | instantly ?
        
           | pontifier wrote:
           | At the event horizon of a large enough black hole, the tidal
           | difference in gravity between your toes and head shouldn't be
           | noticeable. There shouldn't actually be anything special
           | about falling through the event horizon when looking at
           | yourself.
           | 
           | Outside though, you'd see everything start to blue-shift.
           | Things below you would blue shift back to normal, and the
           | universe above you would blue-shift and speed up until you'd
           | see the heat death of the universe. Anything falling in after
           | you would red-shift again as it approached to match your
           | "normal" rate of time. Critically this would include any
           | light or other particles, so it might be very hard to
           | survive.
           | 
           | No matter how fast you go or how weird the space time you are
           | in, your local clock should still tick steadily to you, and
           | you wouldn't notice anything weird.
        
             | pontifier wrote:
             | -Just watched the lecture again, and you wouldn't actually
             | see the outside universe speed up.
        
             | paulmooreparks wrote:
             | > There shouldn't actually be anything special about
             | falling through the event horizon when looking at yourself.
             | 
             | If you went in feet-first, you'd perhaps find it quite odd
             | that your feet never seemed to cross the horizon, as they
             | would have red-shifted so dramatically.
             | 
             | > you wouldn't notice anything weird.
             | 
             | Maybe you wouldn't notice that you never saw your feet
             | cross, since you wouldn't have much time to ponder it
             | before your head crossed as well, but at that point, you
             | surely you would notice that everything below you is black,
             | since all light (and everything else) is now destined for
             | the singularity. That's the very definition of the event
             | horizon. There wouldn't be any reflected light.
        
         | pontifier wrote:
         | Found the lecture. Here is a link to the appropriate part:
         | https://youtu.be/BdYtfYkdGDk?si=iNHi7N68DHxT-52-&t=3182
        
       | ogou wrote:
       | The word "research" in this title is a handy placeholder for
       | indeterminate conjecture. No research happened, it's a theory he
       | made up.
        
         | Frost1x wrote:
         | I would argue that theory is a critical part of the research
         | process and is therefore research.
         | 
         | There's of course a line between simply coming up with ideas
         | that are quickly provably wrong or inconsistent vs generating
         | ideas that are consistent and not quickly falsified. It's
         | especially valuable the ideas are falsifiable and it seems like
         | this is the case here.
         | 
         | As such, theory finds patterns in existing knowns, makes some
         | leaps and tries to connect them. Then empirical evidence can
         | help solidify or falsify those ideas. But we tend not to just
         | connect dots of empirical data without attempting to know the
         | casual relationship, otherwise the connections can be rather
         | nonsensical or may have weak predictive power.
         | 
         | With all that said I didn't read the paper in detail nor am I
         | qualified in this domain to say if it's quackery or a
         | reasonable shot a developing some new theory. It is peer
         | reviewed and published in APS so I suspect it's not complete
         | quackery:
         | https://journals.aps.org/prd/abstract/10.1103/PhysRevD.111.1...
        
           | ogou wrote:
           | A research paper makes use of multiple sources of known
           | provenance and various degrees of authority and relevance. It
           | tries to establish a consensus of knowledge, as close to fact
           | as possible. The phrase "research suggests" is an appeal to
           | authority that implies some kind of academic rigor. A theory
           | paper, which is still useful and important, can be published
           | without any kind of authority. You can just make things up.
        
         | namenotrequired wrote:
         | Would you say Einstein was not a researcher?
        
         | Ar-Curunir wrote:
         | That is what is called research in theoretical fields. Making
         | hypotheses up and then proving implications of those
         | hypotheses. In this case, it yields a falsifiable test: the
         | theory claims the universe should have small positive
         | curvature.
        
       | codingclaws wrote:
       | Could a computer simulation also contain another universe, with
       | virtual black holes that have universes?
        
         | downboots wrote:
         | Can a computer simulate itself?
         | 
         | https://www.youtube.com/watch?v=92WHN-pAFCs
        
       | I_am_tiberius wrote:
       | Sean Carroll says this is absolute nonsense:
       | https://youtu.be/U3uIiv48q98?feature=shared&t=6046
        
       | lkmill wrote:
       | If this is true it almost literally means black holes are a way
       | for universes to make children. If we apply Darwin's principles
       | of the strongest survive this must mean that universes that
       | produce the most black holes are the "best". If correct, what
       | does this actually mean?
        
         | henry2023 wrote:
         | Darwinian logic requires a feedback loop. And because those
         | universes are isolated then there's no "incentive" of a
         | universe to have more "offspring"?
        
           | ben_w wrote:
           | It requires imperfect reproduction where the imperfections
           | alter the probability of further reproduction.
           | 
           | If each black hole in our universe contained a pocket
           | universe with very slightly different laws of physics (to
           | each other and to us), but the same amount of mass-energy on
           | the inside as our universe had when it started, then (1)
           | those pocket universes able to create stars and black holes
           | would also go on to create black holes with pocket universes,
           | but also (2) those pocket universes not able to create black
           | holes, would not create more pocket universes.
           | 
           | I have never seen a reason to think that this could happen,
           | nor why such pocket universes might have more mass on the
           | inside than they appear to have on the outside, but that's
           | the argument.
        
           | jbjbjbjb wrote:
           | There is a theory of cosmological evolution. The child
           | universes have slightly different physical constants and
           | universes that produce more black holes will leave behind
           | more offspring universes so over many generations, the
           | universes evolve toward parameters that favour black hole
           | production.
        
             | pantalaimon wrote:
             | That's what Blowtorch theory predicts, it notes three
             | stages of black hole formation:
             | 
             | - direct collapse after the big bang. Those supermassive
             | black holes now from the center of galaxies and are the
             | earliest and simplest form of how universes reproduced
             | 
             | - stellar collapse, requires the formation of stars, but
             | those can be much more plentyfull than previous
             | supermassive direct collapse black holes, so many more
             | universes will have those
             | 
             | - black holes created by technology. Since black holes are
             | incredibly efficient at converting mass to energy, in a
             | universe that has the capability to form intelligent life,
             | this life will eventually find a way to harness black holes
             | as an energy source. In doing so they would create even
             | more tiny black holes (maybe to power spaceships?), so such
             | universes would form the most offspring.
        
         | pantalaimon wrote:
         | https://en.wikipedia.org/wiki/Cosmological_natural_selection
         | 
         | https://theeggandtherock.com/p/the-blowtorch-theory-a-new-mo...
        
       | hybrid_study wrote:
       | I thought this was already an old general idea; that each black
       | hole ignites the birth of a new universe?
        
       | m3kw9 wrote:
       | This theory actually makes sense. Vs big bang where half of the
       | theory is "let's assume that there is this thing that explodes"
        
       | lagrange77 wrote:
       | If universes can exist in black holes and obviously black holes
       | exist in universes, doesn't that smell like infinite recursion?
        
         | stevenAthompson wrote:
         | What reason do we have to believe that every universe can
         | support black holes? We only have a sample size of 1 here.
        
           | EasyMark wrote:
           | What reason do we have to believe that there is more than one
           | universe?
        
         | vjvjvjvjghv wrote:
         | Black holes all the way down
        
       | Toby1VC wrote:
       | "In my room, redefinin' the meanin' of black holes"
       | 
       | - Earl Sweatshirt
        
         | stevenAthompson wrote:
         | I went to school in a very bad neighborhood. Once I was sent to
         | the office because my math teacher asked me what I was reading
         | about that was soo much more interesting than our textbook. I
         | happened to be reading "A Brief History of Time", so I answered
         | "black holes."
         | 
         | At the time I couldn't understand why my dad laughed about that
         | particular phone call from the principal.
        
           | Toby1VC wrote:
           | Hahahahahahahaha
        
       | afroboy wrote:
       | I'm not a scientist or astrophysicist but i do believe in
       | science, is it ok to believe that we as humans and all our
       | scientific development still very very far from proving anything
       | remotely close to how the universe got created? I feel this
       | subject is for humanity in year 2600 to start discussing it.
       | 
       | Scientist still can show their theories and search papers and i
       | can't understand a shit but i don't believe in any theory that
       | proves how the universe got created.
        
         | philipov wrote:
         | Before we can prove, we must first wonder. We proceed by small
         | steps, and if we don't start discussing it now, 2600 will still
         | be too early.
        
         | belter wrote:
         | If we can't even predict inflation rates maybe we should hold
         | off on explaining the birth of the entire universe, yeah?
        
           | daedrdev wrote:
           | Predicting inflation rates may be harder than discovering the
           | birth of the universe actually, because it would require
           | perfect knowledge of the present and by the time you compute
           | it it's out of date.
        
             | belter wrote:
             | We can claim to simulate the first femtoseconds of the
             | universe...model nuclear detonations in software down to
             | quantum effects....but 340 million citizens buying gas and
             | groceries? That's somehow beyond our grasp... :-)
             | 
             | Maybe the problem isn't complexity, but that science gets
             | arrogant when it drifts into realms where its claims can't
             | be falsified ;-)
        
               | daedrdev wrote:
               | The beginning of the universe is a start state we have
               | theories about, that we can apply our system of physic to
               | calculate once. A computer that calculates an economy
               | might violate the halting problem because it would need
               | to know when it itself is finished to calculate its own
               | electricity costs, as well as every other algorithm in an
               | economy.
        
               | laborcontract wrote:
               | You're fundamentally misunderstanding the difference
               | between biology and physics.
        
               | belter wrote:
               | The difference is clear: https://xkcd.com/435/
        
               | jplusequalt wrote:
               | >Maybe the problem isn't complexity
               | 
               | It most certainly is. Each of those 340 million citizens
               | is a unique person, with unique circumstances. You can't
               | fit an equation to that.
               | 
               | >science gets arrogant where its claims can't be
               | falsified
               | 
               | This article proposes testable predictions?
        
         | ptmcc wrote:
         | It's not about belief, it's about observing, collecting data &
         | evidence, and proposing possible explanations. As new
         | observations and evidence are found the possible explanations
         | are refined. No one credible is claiming hard proof of anything
         | at this point.
        
           | didibus wrote:
           | Agreed, people often mix that up, but you have to adopt a
           | probabilistic mindset, you can believe the coin with land on
           | its head, but you also know that based on the weight and
           | curvature of the coin it will land on its tail 68% of the
           | time you flip it, etc. Then choosing tail is no longer a
           | belief, it is simply going with the choice that is backed by
           | prior observation, experiments, models, etc.
           | 
           | You might still lose, and so you might choose to also believe
           | it will land on tail this time, but the rationale for
           | choosing tail was not based on a belief system, but the going
           | information and where it points too.
        
         | CobrastanJorji wrote:
         | "Proving anything" is kind of fuzzy. We've got very solid
         | evidence that some sort of big bang happened. We can see the
         | galaxies flying away from a common point, and since we can
         | count backwards, we can know roughly when they probably
         | would've been in the same spot. The how and why, and the what
         | happened before, those are very unknown, although we've got a
         | surprising amount of knowledge of what the first few seconds
         | were probably like.
        
         | echelon wrote:
         | I have immense respect for astrophysicists, but the data we're
         | dealing with is extremely far away and relies on a lot of
         | interlocking assumptions.
         | 
         | I stumbled upon this paper [1, 2] last night that challenges
         | the CMB, and thus the underpinning of much of our understanding
         | about the age and evolution of the universe. As a layperson, I
         | don't know the impact factor of the "Nuclear Physics B" journal
         | - if this is just junk or if this is a claim that will pan out.
         | 
         | My point is that it feels like we're building on a lot of
         | observations that are all super indirect. I know I'm just a
         | layperson, but that feels weird when reading assertions about
         | these things.
         | 
         | Our understanding of the universe is relatively new. We don't
         | have a lot of energy or resolution in our observations. The
         | fact that we can sniff the molecular spectra of exoplanets is
         | so amazing and that part feels totally concrete and rock-solid.
         | But I get skeptical when I see claims that we know how the
         | universe began or how it will end. Is our evidence that good?
         | Are our models? Are we basing everything on assumptions?
         | 
         | [1] https://arxiv.org/abs/2505.04687
         | 
         | [2] https://www.youtube.com/watch?v=Xb69yPNgX-Q
        
           | didibus wrote:
           | > But I get skeptical when I see claims that we know how the
           | universe began or how it will end
           | 
           | Absolutely, but you are interpreting it in the rewritten
           | headline money making attention grabbing version.
           | 
           | The original version of the claims always say that from some
           | observation, experiments, and projection from known models it
           | derives that the universe likely began this way, or will end
           | that way, etc.
           | 
           | That means, of all the going hypothesis, this might be the
           | one with the best chances of being true, or close to the
           | truth. It's not an absolute, but its the one that has the
           | most chances due to the evidence behind it.
        
         | didibus wrote:
         | Science is a process, not a source of truth. It has a very
         | practical lens, which is very utilitarian, does the knowledge
         | and models allow for invention or prediction that works in our
         | reality for some current need.
         | 
         | The assumption is, you never really know, but if the model in
         | which the theory says X, is able to predict something in the
         | future or some experiment for Y, than that model appears to
         | better approximate reality. Or is that knowledge and model
         | allowing us to now do something we could not before, etc.
         | 
         | Over time, it course corrects to improve its knowledge and
         | models in ways that show better results for prediction or
         | invention.
        
         | kgwxd wrote:
         | Belief is acting as if something, for which no evidence has
         | been given, is true. Imagination, taken too far. No one is
         | telling you to believe anything here, they're suggesting we
         | search for clues to support or disprove a theory. Or don't,
         | it's up to you.
        
           | LordNerevar76 wrote:
           | That's not the definition of belief. Belief can have various
           | levels of different kinds of evidence behind it. Scientific,
           | historical, philosophical, experiential, etc. A belief could
           | have more or less scientific evidence than other beliefs, but
           | rarely is belief predicated on no evidence whatsoever.
        
             | kgwxd wrote:
             | Do I really have to include the exact definition of every
             | word I ever use? You know damn well I'm talking about blind
             | faith and scientific evidence. And you know damn well OP is
             | completely dismissing a theory because they're confusing it
             | with a demand for blind faith. I don't care what people
             | want to believe, but if they start labeling things
             | incorrectly, I'm going to point it out.
        
         | EasyMark wrote:
         | But that's why science is so cool, it doesn't matter what we
         | believe, it only matters if your theory fits the facts and
         | makes good predictions. If it doesn't, you can chuck it in the
         | bin without guilt. Unlike beliefs, which often can cause
         | psychic trauma if reality doesn't match the belief of the
         | individual.
        
         | serf wrote:
         | I think the phrase 'believe in science' is weird; it's nearly
         | as problematic as "I have faith in science".
         | 
         | It can be, but generally the concept of 'belief' isn't
         | attributed to ground truths; it's just 'the truth', you rarely
         | hear the phrase "I believe 2 and 2 is 4." , it's just '2 and 2
         | is 4.' -- I think that's important.
         | 
         | In fact, a lot of people insert the word 'believe' to insert a
         | concept of self-doubt. "What was our last test results passing
         | rate?" "I believe it was around 95 percent.."
         | 
         | But semantics aside here's the real question : Why do you have
         | some kind of notion that you should 'believe' anything without
         | being able to understand it? Just trust in the world and those
         | around you?
         | 
         | We haven't figured origin yet, so let's get off that, but when
         | a scientist of some sort makes a discovery, they release
         | evidence and methods , and you decide to believe the
         | conclusions without an understanding of the work -- well that's
         | just a display of faith. Faith in the scientist themselves, the
         | system they work within, and the society you're in.
         | 
         | Which leads me to say this : If you make an effort to begin to
         | understand the frameworks and systems which lead to scientific
         | conclusions you can largely remove the faith and belief
         | elements up until you hit the very highest spectrums of each
         | field where speculation comes back into play.
         | 
         | tl;dr : if you 'cant understand a shit', you don't put any leg-
         | work in and make an effort to speak the language, you'll
         | probably end back up in beliefs rather than an ever increasing
         | codex of knowledge -- regardless of the field. That's okay --
         | but it doesn't offer the same benefits as knowledge -- it just
         | lets one say things like "I don't believe in any theory..."
        
         | mkoubaa wrote:
         | You don't believe in science, you believe in a metaphysical
         | claim about science that you haven't articulated.
        
       | HocusLocus wrote:
       | Suggested hard sci-fi light reading: "Cosm" by Gregory Benford,
       | 1999. A universe the size of a bowling ball created in a
       | laboratory. The scientist responsible for it, keeping it safe and
       | on the run from gvt spooks. They want to protect it for as long
       | as it lasts, and since its time is as relative as its size, they
       | won't have long to wait.
        
         | mmh0000 wrote:
         | Added.
         | 
         | Opinions:
         | 
         | A) I love all the scifi book recommendations that cone up on HN
         | 
         | B) i wish you'd all stop recommending great and amazing books.
         | My queue is so backlogged and jammed I'm never going to catch
         | up.
        
           | arto wrote:
           | So many books, so little time...
        
             | mewpmewp2 wrote:
             | If only we had an even bigger universe, we would have more
             | time... is that how it works?
        
               | figassis wrote:
               | Like this? https://hacker-recommended-
               | books.vercel.app/category/5/past-...
        
               | dwaltrip wrote:
               | That's a very cool app, but I think it is missing many,
               | many references to books in HN comments? It only has like
               | 15 total sci-fi books. I don't see any of my comments
               | mentioning some sci-fi books.
        
               | figassis wrote:
               | It's a bit old. I bookmarked it a while ago, I don't
               | think it has an update mechanism. A daily frontpage pull
               | + AI parsing should be enough to keep it up to date.
        
             | baw-bag wrote:
             | There needs to be some kind of hackernews library or
             | goodread. I have enjoyed many books (and some no so much)
             | but always on the look out for books.
        
               | lttlrck wrote:
               | That would be fantastic.
        
           | RGamma wrote:
           | What's a couple dozen books (and video games) in my backlog
           | when I have a thousand websites there?
        
           | fibonachos wrote:
           | Same here. My interest in the Sci-Fi genre started with an HN
           | comment recommending Blindsight, by Peter Watts.
           | 
           | Several comments and sci-fi series later, and I'm currently
           | reading about spacefaring sentient spiders.
        
           | donohoe wrote:
           | Please share the queue!
        
         | landtuna wrote:
         | This sounds similar to Horton Hears a Who.
        
           | jldl805 wrote:
           | They exist in the same cinematic universe.
        
         | Xophmeister wrote:
         | I seem to remember a similar Star Trek episode; DS9, IIRC.
        
           | ars wrote:
           | I remember that, and the enormous plot hole that they could
           | move the thing in a transporter!
        
           | throwawaymaths wrote:
           | "playing god", s2e17
        
         | sleepybrett wrote:
         | Rick and Morty episode (season 2 episode 6, 'The Ricks Must be
         | Crazy') where it turns out rick has created a whole universe
         | inside his spaceship battery who's whole purpose is to produce
         | energy to run his spaceship. A scientist within this microverse
         | creates a miniverse ....
        
         | veqq wrote:
         | Microcosmic God - Theodore Sturgeon (1941)
        
       | pantalaimon wrote:
       | Reminds me very much of Blowtorch Theory that was discussed here
       | recently
       | 
       | https://news.ycombinator.com/item?id=44115973
        
       | profsummergig wrote:
       | The big bang sounds like how a computer would interpret being
       | turned on.
       | 
       | Anyone else think this is what happened?
        
         | bigbuppo wrote:
         | Nope, it's just you applying the thing you think you know to
         | something you don't know.
        
         | BitwiseFool wrote:
         | Computers refer to this as 'the Big Boot'.
        
           | pontifier wrote:
           | Imagine a being inside a turing machine wondering what came
           | before it was turned on... implying the turing machine is
           | even on and we're not just looking at the set of all possible
           | rule sets on a similarly abstracted mathematical chart.
        
           | profsummergig wrote:
           | One day someone's going to reboot that computer and I'm going
           | to lose all my carefully curated trauma.
        
       | larodi wrote:
       | it is funny the fact that author decided to explain who Galileo
       | was
        
       | johnwheeler wrote:
       | So that's what that big blob in the Mandelbrot set is. It's a
       | diagram of our fractal universe.
        
       | ck2 wrote:
       | There's a PBS Space Time for that (from three years ago)
       | 
       | https://www.pbs.org/video/could-the-universe-be-inside-a-bla...
       | 
       | https://www.youtube.com/watch?v=jeRgFqbBM5E
        
         | AppleBananaPie wrote:
         | Will hacker news side with ChatGPT or real physicists? :D
         | 
         | Love PBS space time !
        
       | tug2024 wrote:
       | Why does it always have to by "hyperbolic" instead of parabolic?
        
       | TheRealPomax wrote:
       | Very high "Time started when someone clicked start" - "cool, how
       | did events happen before they clicked start?" factor title.
        
       | hshshshshsh wrote:
       | Big bang theory no longer excites me. As long as we can't explain
       | consciousness all these theories are pointless. All theories mere
       | appearances in consciousness including the universe and
       | everything we experience.
       | 
       | Consciousness has the property to render infinite universes and
       | theories.
       | 
       | But we have no clue how universe creates consciousness.
        
         | bufferoverflow wrote:
         | First define consciousness such that the definition
         | differentiates you from a computer with a webcam.
        
           | hshshshshsh wrote:
           | You cannot define consciousness. You can only experience it.
           | In fact consciousness is the only thing you will ever
           | experience.
        
             | saulpw wrote:
             | Perhaps you should use 'sentience' or something more
             | precise to mean 'qualia-experiencing'. The word
             | 'consciousness' is quite overloaded and thus trips people
             | up who haven't thought about this as extensively as you
             | have. In particular many people take it to mean "self-
             | awareness" (whether correctly or not), but it seems obvious
             | to me that there are many sentient beings which lack self-
             | awareness but still have an internal experience.
        
               | hshshshshsh wrote:
               | Yes. Self awareness is just another content inside
               | consciousness.
        
           | legohead wrote:
           | You can measure various aspects of a computer. You can't
           | measure consciousness.
        
             | bufferoverflow wrote:
             | That's not a definition. Depending on the definition, it
             | may be possible to measure it.
        
               | hshshshshsh wrote:
               | You cannot measure consciousness. You are consciousness
               | thinking of itself as the human. Measurement is an event
               | appearing in consciousness done by humans.
               | 
               | It's like persons inside GTA talking about measuring the
               | Samsung monitor. It makes no sense cause they can never
               | see the monitor or locate it. They appear in the monitor.
        
               | consz wrote:
               | You absolutely can measure "various aspects of
               | consciousness" -- for example, "how much of the last 24h
               | has this consciousness been awake" seems simple. So your
               | definition seems kind of weak, could you be more precise?
               | 
               | Conversely, in your definition, is consciousness the only
               | "thing" that you would describe as not being able to
               | measure various aspects about it? Are there any other
               | objects or concepts which you also cannot measure various
               | aspects about? If yes, what differentiates _those_ things
               | from consciousness?
        
         | everdrive wrote:
         | Consciousness is a specific biological adaptation which is
         | primarily focused in the management of social relationships,
         | status, and the prolonged adolescence of children. (and their
         | required care)
         | 
         | There's no reason to think that consciousness is an important
         | question in the objective sense; it just matters to people.
         | (and rightfully so) People wondering about consciousness in the
         | universe might be akin to dogs wondering what the big bang
         | smelled like.
        
           | hshshshshsh wrote:
           | Are we both talking about the same thing?
           | 
           | https://en.m.wikipedia.org/wiki/Consciousness
        
           | woopsn wrote:
           | What is an important question in the objective sense? Is
           | life, or no because that just matter to life? It seems
           | oxymoronic, "objective question", "objectively important".
           | 
           | I don't follow GP's sort of solipsist (?) take, but would say
           | question of whether big bang took place in a black hole is
           | pointless compared to life/experience and how they arise.
        
             | hshshshshsh wrote:
             | Solipsism is the question whether it's all made up by my
             | mind and only my mind exists.
             | 
             | I am not interested in that.
             | 
             | I am interested in the thing in which all the made up stuff
             | appears. And the thoughts and mind appears. Even I appear
             | in that.
        
       | afarah1 wrote:
       | Interesting read, but even if we assume the author is correct,
       | and the cosmos formed as a black hole in a larger universe, the
       | question remains, how did this larger universe formed, then?
       | Might just be impossible to know.
        
         | paleotrope wrote:
         | A larger black hole
        
         | alkonaut wrote:
         | It's turtles all the way down
        
           | onlyrealcuzzo wrote:
           | Black holes all the way up.
        
         | kgwxd wrote:
         | if we assume the author is correct, it would cease to be a
         | scientific endeavor.
        
           | analog31 wrote:
           | I'd put it a bit differently, that it remains a scientific
           | endeavor, but leaves us in the same predicament as we're in
           | now, which is the difficult work of forming a scientific
           | theory that can only be tested indirectly.
        
         | timewizard wrote:
         | It may just be that the physical conditions of our universe
         | just prior to the big bang are indistinguishable from that of
         | the interior of black holes.
         | 
         | In that sense black holes are areas where our universe has
         | reverted from it's low entropy state all the way back to the
         | initial nearly infinite entropy state.
        
         | mewpmewp2 wrote:
         | But who would be as cruel to put us here without giving us
         | those answers? Who? And where did that entity come from?
        
           | mrbungie wrote:
           | Maybe there was no cruelty, and we were just plain matter
           | that fell into our encapsulating black hole. Like what
           | happenswith our own universes black holes.
        
           | amelius wrote:
           | There is no other entity. We're nothing. An algebra of
           | nothing. Combine nothing with nothing in various ways (like
           | S-terms) and it gives you physics, among many other things.
           | From the inside we see a universe, from the outside you would
           | see nothing.
        
             | mewpmewp2 wrote:
             | As an agnostic I agree, but none the less it is a whole,
             | absurd joke to be here without any answers and I demand
             | someone to answer me.
        
               | largbae wrote:
               | We apologize for the inconvenience.
        
               | mewpmewp2 wrote:
               | This needs to be escalated. Who is your manager?
        
               | mindcrime wrote:
               | You are Number 6.
        
               | ndsipa_pomu wrote:
               | Be seeing you
        
               | foobar1962 wrote:
               | That's _almost_ a HHGG reference.
        
               | satiric wrote:
               | If you agree with the above comment, doesn't that make
               | you an atheist, not agnostic?
        
               | mewpmewp2 wrote:
               | I used to think that I was an atheist, but I realized
               | nothing can be proven presently in any way even if I have
               | opinions, so I decided I have to be agnostic.
               | 
               | So e.g. I have hunches that there's no way there is a God
               | that's in any way as religions might think it is, and I
               | do have a hunch that we somehow happened from probably
               | deterministic chain reactions, but it's a hunch, it's
               | hard to call it a belief, or it's hard to think that I
               | believe there is no God. It's more like a hunch or a
               | thought. Because for all I know we could be some Alien's
               | schoolwork project, but I don't think we are.
               | 
               | In any case as a human I feel like I have evolutionary
               | drive to hold someone responsible, so again I demand
               | whoever is behind all of that to give us those answers.
               | But that is my evolutionary drive, not that I think
               | there's actually someone like that. It's the conflict of
               | evolutionary brain vs the logical thoughts brain.
               | 
               | These different parts in the brain can also agree to many
               | different things, which can ultimately make me much more
               | agreeable person, if I decide to pick one of those
               | opinions.
               | 
               | But I can be very disagreeable too, because I think Big
               | Five said it can lead to success?
        
               | ndsipa_pomu wrote:
               | > I used to think that I was an atheist, but I realized
               | nothing can be proven presently in any way even if I have
               | opinions, so I decided I have to be agnostic.
               | 
               | As an atheist myself, I find your type of agnosticism to
               | be overly generous to the religious theories. Do you also
               | think that Russell's Teapot might exist or do you have a
               | limit of unlikeliness that you draw the line at?
               | 
               | https://en.wikipedia.org/wiki/Russell's_teapot
        
               | amelius wrote:
               | Why didn't anyone tell Musk to put a teapot in space
               | instead of a Tesla?
        
               | StanislavPetrov wrote:
               | >So e.g. I have hunches that there's no way there is a
               | God that's in any way as religions might think it is, and
               | I do have a hunch that we somehow happened from probably
               | deterministic chain reactions, but it's a hunch, it's
               | hard to call it a belief, or it's hard to think that I
               | believe there is no God.
               | 
               | Saying that you know for certain that there is no god(s)
               | is exactly the same as saying you know for sure that
               | there is a god(s). Being agnostic is the realization that
               | you can't be sure one way or the other. We are not
               | omniscient and our reasoning abilities are not flawless.
               | You might have your strong suspicions one way or the
               | other about whether there is a god, but if you aren't
               | certain (as many people are) I consider that as agnostic.
        
               | foobar1962 wrote:
               | Atheists are people that don't _bleieve_ there is a God.
               | Agnostics are people who don 't _know_ they are atheists.
               | -- Aron Ra
        
               | mewpmewp2 wrote:
               | I can't 100% prove that I'm an atheist, so I'm definitely
               | agnostic. The brain structure is constantly evolving and
               | it's unclear how that exactly works. What is a "belief"
               | any way, and what does it matter for?
        
               | StanislavPetrov wrote:
               | That just seems to me a terribly flawed statement. I'm
               | agnostic. Maybe there is a god, maybe there isn't, who am
               | I to know? It always seems like incredible hubris to me
               | when someone claims not only to know for certain one way
               | or the other, but project their baseless beliefs onto
               | others.
        
               | haswell wrote:
               | In practice, atheists are people who think they _know_
               | there is no god. Agnostics are people who realize they
               | don't know much at all about anything related to the
               | origins of things and realize they don't want to hold
               | unprovable dogmatic beliefs like the religious people do.
               | 
               | I considered myself an atheist for most of my life. As I
               | got older and learned more, this shifted. These days I
               | consider myself agnostic.
               | 
               | If atheism was defined as believing _a specific kind of
               | god_ (e.g. the "father god in the sky that created all
               | things in 6 days") does not exist, I'd still consider
               | myself an atheist.
               | 
               | But my agnosticism comes from an acknowledgment of our
               | fundamentally limited understanding of certain aspects of
               | existence, and the implications of that specific lack of
               | understanding.
               | 
               | It's not as if I believe "well maybe the god of Abraham
               | could be real after all but I don't know" (it seems far
               | more likely that if there's a god, he/she/it/they are
               | closer to being the stuff of existence than some
               | standalone entity). It's more that I withhold belief
               | entirely and don't make absolute claims that are
               | philosophically untenable.
               | 
               | If we figure out how consciousness works or achieve
               | breakthroughs in physics, I could imagine calling myself
               | an atheist again. Until then, agnosticism seems like the
               | most intellectually honest position.
        
           | mock-possum wrote:
           | Oh that was me - I figured if I let you guys work it out for
           | yourselves, it'd be more meaningful or whatever.
           | 
           | As for where I came from, I gotta admit I feel curious about
           | that too, but mostly I'm just happy to be here. Real excited
           | to see what you do next.
        
             | noworriesnate wrote:
             | I believe you, could you please give me 1000 upvotes? If
             | you do I promise to spread the good news everywhere.
        
           | tstrimple wrote:
           | This is why the "but the universe couldn't spawn out of
           | nothing!" style arguments are so annoying. They completely
           | accept that an all powerful all knowing entity could exist
           | for all of time and not need a creator without any supporting
           | evidence. But the origin of the universe specifically needs
           | to be explained in detail or science is a sham.
        
         | johnwheeler wrote:
         | My theory: There's no such thing as before and after "it". It
         | is it.
        
           | ckdot wrote:
           | Block Universe. The more you think about it, the more
           | probable it seems. Why should a universe pass time like a
           | movie, if all moments could exist simultaneously? If there is
           | no time, and it's just a simulation formed in our brain,
           | there doesn't have to be a beginning nor end.
        
             | ndsipa_pomu wrote:
             | However, a complete lack of time doesn't fit with our
             | observations and we can measure relativistic effects where
             | time gets distorted (e.g. fast moving particles that last
             | much longer than you'd expect due to relativity)
        
               | jiggawatts wrote:
               | GR is compatible with a block universe. If anything, the
               | relativity of simultaneity strongly suggests that we live
               | in a block universe!
        
           | ttctciyf wrote:
           | What about "bit"? Doesn't that come before "it", Mr Wheeler?
           | :)
        
         | anal_reactor wrote:
         | I feel like quantum physics is gently pointing us towards the
         | idea "everything you can imagine is real at once". As in, all
         | possible universes and physics systems and whatnot do exist in
         | some sense of this word, and we happen to inhabit one. Just
         | like Earth is a totally unremarkable planet in a totally
         | unremarkable solar system in a totally unremarkable galaxy,
         | except we popped up here so for a long time we thought there's
         | something deeply special about Earth.
        
           | layer8 wrote:
           | Quantum mechanics doesn't imply at all that everything
           | possible is actual. That is a misconception.
           | 
           | I do agree that it makes sense, but not because of what
           | quantum mechanics says.
        
             | anal_reactor wrote:
             | Yes, it doesn't imply, but parallel universes is one of
             | possible interpretations.
        
               | layer8 wrote:
               | If you are referring to the many-worlds interpretation,
               | that's exactly what I'm talking about. There is no
               | implication in many-worlds that every conceivable world
               | exists as a branch of the actual wave function.
               | 
               | See also https://news.ycombinator.com/item?id=44253344.
        
               | notfed wrote:
               | I fail to see how this doesn't lead to "every possible
               | world". Maybe some edge cases are ruled out, but it seems
               | to imply every possible world as far as what that means
               | to the imagination.
        
               | layer8 wrote:
               | It is constrained by whatever you take as the initial
               | conditions. The quantum state of the universe is a
               | specific and precise thing, as well as how it evolves
               | over time. It can be taken as a vector in Hilbert space
               | that evolves according to the Schrodinger equation. There
               | is no implication that the resulting path will have it
               | visit every point in Hilbert space, or that the slices of
               | the wave function that represent individual "worlds"
               | somehow cover all worlds present in the unvisited points.
        
               | grumple wrote:
               | The math does imply infinite universes. There are many
               | physicists who believe that all these worlds do exist.
               | 
               | See also: https://en.wikipedia.org/wiki/Many-
               | worlds_interpretation
               | 
               | And a video: https://www.youtube.com/watch?v=dzKWfw68M5U&
               | list=PLsPUh22kYm...
        
               | layer8 wrote:
               | Infinite universes doesn't imply every possible universe.
               | I don't disagree about them existing.
        
           | decae wrote:
           | Not only does the sun not rotate around us, the rest of the
           | galaxy doesn't even care to think that we exist. An
           | interesting evolution in thought nonetheless.
        
           | Rattled wrote:
           | I find it more useful to anchor the concept of "real" in what
           | one has direct access to. Beyond that there are many ways to
           | describe our shared reality and the space of possible
           | realities, including the past and future, some of which are
           | more real than others, and go far beyond what we can imagine.
           | Quantum physics gives us a language to expand what we can
           | describe and imagine.
        
         | layer8 wrote:
         | Maybe the larger universe is identical to the contained
         | universe, like a fractal. That would solve the question. ;)
        
           | teaearlgraycold wrote:
           | Would be fun if we find a function f(state, time) such that
           | for f(singularity, 14 billion years) we get our current
           | universe. i.e.: every singularity turns into our exact
           | universe.
        
             | unsupp0rted wrote:
             | Implying there's no such thing as randomness, at any level?
        
               | teaearlgraycold wrote:
               | No randomness when taking everything into account. I'm
               | not an expert but I still hold out hope that if you know
               | more about the universe than humanity does everything
               | will be known to be deterministic.
               | 
               | Also implies that all singularities of the same mass are
               | identical. I think this should be less bold of a
               | statement. Let's speculate that the more mass in the
               | singularity would correspond to higher iterations in
               | something like the Mandelbrot set. More of a resolution
               | enhancement.
               | 
               | More if a scifi prompt than anything else to be fair.
        
               | unsupp0rted wrote:
               | That would mean that beings getting to know everything
               | about the universe at some point and realizing it's
               | deterministic was always pre-determined
        
               | tiltowait wrote:
               | While I doubt you're unique in this, I think this is the
               | first time I've seen someone say they _hope_ there's no
               | such thing as free will.
               | 
               | Can you explain why you hope everything is deterministic?
        
               | teaearlgraycold wrote:
               | Might just be a reflection of my enjoyment of life. I've
               | been very lucky on most aspects. Perhaps if things were
               | worse I'd wish for the knowledge that it could have gone
               | differently.
               | 
               | But also it would be super trippy and interesting.
               | Knowing just the mass of the universe you'd be able to
               | peer into any time, past or present, and see exactly what
               | happened. But then what happens around areas where people
               | look into the local time? This happens in the show Devs.
               | So not at all a new idea in scifi.
        
               | nwienert wrote:
               | Not much concern for all the people less lucky than you?
        
               | teaearlgraycold wrote:
               | Just explaining where my ideas on determinism might come
               | from. It's not as though I can change the laws of physics
               | to be one way or the other.
        
           | downboots wrote:
           | Might I suggest Brouwer's theorem while we figure it out
        
             | joshdavham wrote:
             | Could you elaborate? It's been a while since I've done any
             | real analysis/etc.
        
               | downboots wrote:
               | A 2D version: If you have a map of the place you're in,
               | there must be a point on the map that's in the exact
               | place it represents.
        
           | mikrl wrote:
           | Then we gotta find the black hole in our universe that
           | contains that universe, and nuke it before they come to take
           | our fluids!
        
             | revskill wrote:
             | Why selfish ???
        
               | bregma wrote:
               | It's imperative we maintain Purity Of Essence. It will
               | bring Peace On Earth.
        
             | skeaker wrote:
             | Might not be the best idea, unless we just so happen to be
             | all the way at the top of the sequence[1]...
             | 
             | 1 - https://qntm.org/responsibility
        
         | postalrat wrote:
         | That's a very 3D way to think of a universe.
        
         | dboreham wrote:
         | It's just recursion in the simulator.
        
         | conradev wrote:
         | This theory is in the same space:
         | 
         | https://en.wikipedia.org/wiki/Cosmological_natural_selection
         | 
         | I don't think it has a hypothesis for the origin, though
        
           | phatskat wrote:
           | See also the recent HN discussion about Blowtorch Theory,
           | which has roots in (but doesn't necessitate) CNS
        
             | conradev wrote:
             | building on ten years of earlier research for a book on
             | cosmological natural selection
             | 
             | This is awesome, thank you! I'm interested in the general
             | space
             | 
             | I loved this overview on our current approaches to measure
             | the expansion: https://youtu.be/WNyY1ZYSzoU
        
         | PUSH_AX wrote:
         | Just casually adding the biggest question its possible to ask
        
         | randomtoast wrote:
         | Questions like what was before the big bang or what is outside
         | of our universe seem to be quite natural. However, we still
         | don't know if these questions are well defined and have a
         | proper meaning. For instance, a few hundred years ago, one
         | might have asked, what happens if I go to the edge of the
         | (flat) earth? Or one might ask: What is north of the north
         | pole?
        
           | timonofathens wrote:
           | > What is north of the north pole?
           | 
           | I really like this analogy for "what is outside of our
           | universe", thank you
        
           | helsinki wrote:
           | Thanks, GPT 4.1. It told me the same thing twelve hours ago
           | when I asked it what was at the top. "what's north of the
           | North Pole"?
        
             | randomtoast wrote:
             | It is well possible that GPT-4.1 references Sean Carroll,
             | either directly or by regurgitation.
             | 
             | > One sometimes hears the claim that the Big Bang was the
             | beginning of both time and space; that to ask about
             | spacetime "before the Big Bang" is like asking about land
             | "north of the North Pole."
             | 
             | Source:
             | https://www.preposterousuniverse.com/writings/dtung/
             | 
             | I'm a regular listener of his Mindscape podcast, and that's
             | where I got this phrase. I can highly recommend his
             | podcast: https://www.preposterousuniverse.com/podcast/
        
       | sullivantrevor wrote:
       | my feeling is that the beginning of the universe is so
       | unbelievably unexplainable and strange that we will never truly
       | understand its origin
        
       | GodelNumbering wrote:
       | This brings to mind something I keep thinking about for years
       | (mostly from watching too many physics videos).
       | 
       | - Gravity "slows" the time down, gravitational singularity should
       | bring the time to a halt
       | 
       | - Suppose there is a quantum process that makes the true
       | singularity impossible, so all black holes immediately expand
       | right back
       | 
       | - Looking at it from our time scales, even if the singularity
       | existed for a moment, it would appear that "infinite" time has
       | passed while from the black hole's perspective, the expansion was
       | instantaneous.
       | 
       | - From earth's perspective, if the singularity ever existed in a
       | black hole, it stands to reason that when the time "resumes" from
       | a black hole expansion, it won't fall into any of our known
       | timelines since infinite time would have passed.
        
         | cogman10 wrote:
         | Along those lines, makes me wonder if the "bang" is in fact the
         | fact that after the time compression, all matter/energy is
         | effectively arriving at the same point all at once.
         | 
         | Assuming our universe eventually collapses into a few black
         | holes, perhaps the spawn of a new universe is simply all the
         | matter and energy of our universe arriving at a new point in...
         | time? an infinite amount of time in the future.
         | 
         | Also, really mind bending to think the universe may just be an
         | infinite series of black hole explosions with no beginning. It
         | is because it always was.
        
       | avmich wrote:
       | > But how come Penrose's theorems forbid out such outcomes? It's
       | all down to a rule called the quantum exclusion principle, which
       | states that no two identical particles known as fermions can
       | occupy the same quantum state (such as angular momentum, or
       | "spin").
       | 
       | > And we show that this rule prevents the particles in the
       | collapsing matter from being squeezed indefinitely. As a result,
       | the collapse halts and reverses. The bounce is not only possible
       | - it's inevitable under the right conditions.
       | 
       | Then how comes the neutron stars collapse into black holes
       | despite obeying the exclusion principle?
        
         | nick3443 wrote:
         | Is it because the black hole is a macro distortion of spacetime
         | and not a local quantum property?
        
         | 1270018080 wrote:
         | With enough mass, there is enough energy from gravity to put
         | all fermions into different states, so the collapse continues
        
           | truculent wrote:
           | Are you suggesting that the authors' "bounce" would only
           | happen if the energy was not enough to put them into
           | different states?
        
         | colechristensen wrote:
         | >Then how comes the neutron stars collapse into black holes
         | despite obeying the exclusion principle?
         | 
         | One of the ways to overcome one of the levels of this
         | degeneracy pressure is electron capture which is the opposite
         | of a kind of beta decay. Squeeze hard enough and a proton
         | combines with an electron to form a neutron and a neutrino.
         | 
         | But there are several proposed levels of degenerate matter in
         | neutron stars, the idea being that one (final?) level of this
         | degenerate matter is dense enough to make an object smaller
         | than its schwarzschild radius. Uncertainty is high because we
         | have no current methods to observe any of this kind of matter.
         | 
         | What goes on inside the schwarzschild radius is another mystery
         | we don't have answers from, but there are lots of ideas with
         | various levels of legitimacy.
         | 
         | Quantum physics in and around singularities or things we think
         | are singularities is not understood.
        
         | goodcanadian wrote:
         | _Then how comes the neutron stars collapse into black holes
         | despite obeying the exclusion principle?_
         | 
         | Different exclusion principle. For neutron stars, it is the
         | Pauli exclusion principle (IIRC) which creates neutron
         | degeneracy pressure. Enough mass and gravity can overcome it
         | forming a black hole. The article is talking about quantum
         | exclusion which happens at a much smaller scale. I don't know
         | much about it because that exceeds the limits of my degree.
        
       | holoduke wrote:
       | I still don't understand from the article why the bounce effect
       | results in an accelerated expansion of space time. Is the black
       | hole (our universe) in the parent universe getting bigger? And
       | why is that non linear?
        
       | normalaccess wrote:
       | I've always liked the Idea that black holes accelerate matter
       | faster than light behind the event horizon propelling it back in
       | time creating a singular white hole at the first moment.
       | 
       | There are many many reasons why this is a dumb idea and it's just
       | as much of a paradox as any other naturalistic creation theory.
        
       | lofaszvanitt wrote:
       | So the expansion comes from the bounce. And we are in a dormant
       | supermassive black hole of sorts. How would it look like in our
       | world if the mother blackhole is actively gobbling up matter from
       | the parent universe?
        
       | wrcwill wrote:
       | while it doesn't take away from the article, i find it worrying
       | that it seems mostly written with chatgpt
       | 
       | "This is not just a technical glitch; it's a deep theoretical
       | problem that suggests we don't really understand the beginning at
       | all."
       | 
       | "The bounce is not only possible - it's inevitable under the
       | right conditions."
       | 
       | ugh
        
         | AppleBananaPie wrote:
         | There was a physicist who made a video making fun of crackpot
         | theories from engineers and reading the comments we're all
         | happy to put forth our completely unsubstantiated opinions with
         | zero understanding of the math and observations involved
        
       | PartiallyTyped wrote:
       | I thought the Pauli exclusion principle is why we have neutron
       | stars, ie the degeneracy of a star results in the fusion of
       | electrons and protons to form neutrons and emit neutrinos.
       | 
       | What is preventing the collapse in this case and results in a
       | bounce?
        
       | ahuth wrote:
       | Cool article!
       | 
       | I can hear Sean Carrol saying, though, that:
       | 
       | 1. We know general relativity isn't complete, because it doesn't
       | take quantum mechanics into account.
       | 
       | 2. We can't say whether this is right because we don't know the
       | quantum theory of gravity.
       | 
       | But I don't actually know what I'm talking about.
        
       | truculent wrote:
       | > The black hole universe also offers a new perspective on our
       | place in the cosmos. In this framework, our entire observable
       | universe lies inside the interior of a black hole formed in some
       | larger "parent" universe.
       | 
       | What specifically is meant by interior? Does this mean "within
       | the event horizon" or something else?
        
       | brtkwr wrote:
       | Notebook LM version
       | https://notebooklm.google.com/notebook/bb55f273-a5e8-461a-b7...
        
       | TheOtherHobbes wrote:
       | Which suggests that:
       | 
       | 1. You can have black holes inside black holes.
       | 
       | 2. Potentially each black hole is a universe - although some are
       | much smaller and less interesting than others.
        
       | hateful wrote:
       | I've always had this idea that perhaps the whole universe had
       | already collapsed into many black holes and perhaps each galaxy
       | was actually formed via hawking radiation. Then our galaxy came
       | out of Sagittarius A*.
        
       | DrNosferatu wrote:
       | Does this model predict the CMB peaks?
        
       | taeric wrote:
       | I'm curious on what is "at stake" with this? The close lists a
       | couple of predictions that this can lead to. I'm assuming they
       | will be important in a far future time? Or do these help with
       | some more near term problems?
       | 
       | Edit: I hasten to add that I'm not asking to undermine the
       | research. Seems the more the merrier, there. Genuinely curious on
       | what some of this could lead to.
        
       | gghoop wrote:
       | I haven't read the paper, it's probably well beyond me, but I
       | have always felt that the presumed existence of a singularity had
       | to be the result of incomplete theory.
        
       | blindriver wrote:
       | Research? Sounds more like speculation.
        
         | ajkjk wrote:
         | Don't suppose you read the paper..?
        
         | tengbretson wrote:
         | It's probably best not to jump to conclusions until we see it
         | replicated in another universe.
        
       | jarend wrote:
       | The article is based on a physics paper (arXiv:2505.23877), not
       | management theory or institutional metaphors.
       | 
       | What the paper actually proposes is that the Big Bang may have
       | been a gravitational bounce inside a black hole formed in a
       | higher-dimensional parent universe. Quantum degeneracy pressure
       | stops the collapse before a singularity forms. From the outside,
       | it looks like a black hole. From the inside, it evolves as a 13.8
       | billion year expansion. That is general relativity applied across
       | frames.
       | 
       | Simply put this is a relativistic collapse model with quantum
       | corrections that avoids singularities and produces testable
       | predictions, including small negative curvature and a natural
       | inflation-like phase.
        
         | ASalazarMX wrote:
         | So, could the same interaction create planar universes inside
         | our own black holes? Linear universes inside those as well?
         | 
         | It's incredible how big a 4-D universe would have to be to
         | contain our own, even crazier if there are more levels; but our
         | own universe could contain easily uncountable planar universes.
        
           | dleeftink wrote:
           | Isn't it more a matter of how space is folded in higher
           | dimensions rather than an increase in volume that accounts
           | for containment? There is plenty of space in the corners:
           | 
           | [0]: https://observablehq.com/@tophtucker/theres-plenty-of-
           | room-i...
        
         | thechao wrote:
         | Sigh: https://arxiv.org/abs/2505.23877
        
         | eggn00dles wrote:
         | seems like this is just giving up on quantum gravity and saying
         | the pauli exclusion principle will hold regardless of the
         | gravitational force.
        
         | Agentlien wrote:
         | > What the paper _actually_ proposes [...]
         | 
         | (Emphasis mine)
         | 
         | I haven't read the paper yet, but this sounds like a (good)
         | summary of exactly what the article is saying. It makes me
         | wonder what, if anything, you feel is different from the way
         | you put it and the way it is explained in the article? As a
         | layman they seem the same to me.
        
           | Voloskaya wrote:
           | The article was written by the main author of the paper, so
           | yes, it's a good summary :)
        
             | Agentlien wrote:
             | I meant that the parent comment to mine was a good summary
             | of the article.
             | 
             | However, the comment was worded as if it meant to highlight
             | some difference between how the article summarized the
             | paper and what the paper is actually saying. Since I
             | couldn't see a difference between the above poster's
             | summary and that in the article, I was curious what I was
             | missing.
        
         | empiricus wrote:
         | Looking at the paper, I don't see any higher dimensions of the
         | parent universe, it is still using the same 4D General
         | relativity framework for the parent.
        
         | potamic wrote:
         | They have basically disproved Penrose-Hawking's theories of
         | singularity? Isn't that like a pretty big deal? To people
         | working in this field, what is the reaction to this paper?
        
         | leiroigh wrote:
         | >in a higher-dimensional parent universe
         | 
         | That's incorrect: The parent universe is not higher-
         | dimensional, it's the same good old 3+1 as our universe.
         | 
         | What they propose is: Let's take our good old GR, and start
         | with a (large, dilute) compactly supported spherically
         | collapsing collapsing cloud of matter. During that, you get an
         | event horizon; afterwards, this looks like a normal black hole
         | outside, and you never see the internal evolution again
         | ("frozen star", it's an event horizon). Inside, you have the
         | matter cloud, then a large shell of vacuum, then the event
         | horizon.
         | 
         | Quantum mechanics suggests that degeneracy pressure gives you
         | an equation of state that looks like "dilute = dust" first, and
         | at some point "oh no, incompressible".
         | 
         | They figure out that under various assumptions (and I think
         | approximations), they get a solution where the inside bounces
         | due to the degeneracy pressure. Viewed from inside, they
         | identify that there should be an apparent cosmological
         | constant, with the cosmological horizon somehow (?)
         | corresponding to the BH horizon as viewed from the outside.
         | 
         | All along the article, they plug in various rough numbers, and
         | they claim that our observed universe (with its scale, mass,
         | age, apparent cosmological constant, etc) is compatible with
         | this mechanism, even hand-waving at pertubations and CMB an-
         | isotropies.
         | 
         | This would be super cool if it worked!
         | 
         | But I'm not convinced that the model truly works (internally)
         | yet, too much hand-waving. And the matching to our real
         | observed universe is also not yet convincing (to me). That
         | being said, I'm out of the cosmology game for some years, and
         | I'm a mathematician, not a physicist, so take my view with a
         | generous helping of salt.
         | 
         | (I'm commenting from "reading" the arxiv preprint, but from not
         | following all computations and references)
         | 
         | PS. I think that they also don't comment on stability near the
         | bounce. But I think that regime is known to have BKL-style
         | anisotropic instability. Now it may be that with the right
         | parameters, the bounce occurs before these can rear their
         | heads, and it might even be that I missed that they or one of
         | their references argue that this is the case if you plug in
         | numbers matched to our observed universe.
         | 
         | But the model would still be amazing if it all worked out, even
         | if it was unstable.
        
           | mr_toad wrote:
           | > with the cosmological horizon somehow (?) corresponding to
           | the BH horizon as viewed from the outside.
           | 
           | That's not mentioned in the summary. After inflation the
           | event horizon would not exist.
        
         | cbolton wrote:
         | You mean small positive curvature.
        
       | Noelia- wrote:
       | When I first heard the idea that our universe began inside a
       | black hole from another one, it felt like something out of a sci-
       | fi movie. But the more I sit with it, the more it starts to feel
       | like the universe is quietly nudging us, saying it has a much
       | bigger story to tell.
       | 
       | If the Big Bang was just a moment in someone else's universe,
       | then maybe everything we know is just one chapter in a book far
       | larger than we can imagine.
        
       | J253 wrote:
       | So if our universe is inside a black hole from a parent universe,
       | does that mean every black hole in our universe contains its own
       | child universe? We could be living in cosmic Russian dolls all
       | the way down?
        
       | EMM_386 wrote:
       | These type of 'theories' I dislike only because they don't get to
       | the root of the problem.
       | 
       | It is the same for 'multiverse' where that is used to explain
       | literally anything 'it's like that in this universe but not the
       | others'.
       | 
       | Sure, we can get creative and explain the Anthropic Principle by
       | mentioning the multiverse.
       | 
       | But none of this answers how something comes from nothing.
       | 
       | Not the vacuum of space and its 'quantum foam' where particles
       | jump in from nowhere.
       | 
       | Because that's not 'nothing'.
       | 
       | One of these nothings ... such as level 9. No possibilities.
       | 
       | https://closertotruth.com/news/levels-of-nothing-by-robert-l...
        
         | jakeinspace wrote:
         | I won't touch level 8/9 nothings, other than to say I don't
         | think they're coherent. But I am of the metaphysical camp that
         | thinks there will be at least some small ground truth which
         | physical law or object which cannot be reduced, an axiom of
         | nature. Physics unfortunately will probably always be limited
         | in distinguishing between basic facts which are truly
         | irreducible, and those which are simply limits of our
         | observational abilities. That's the thing that bothers me; even
         | if there were a single beautiful law of nature that just IS,
         | one which we actually manage to postulate based on evidence, we
         | will never know for sure. GR definitely has a beautiful
         | mystique, it's a shame that it's most likely just a
         | mathematical approximation.
        
         | ajuc wrote:
         | > But none of this answers how something comes from nothing
         | 
         | Why do you assume there was nothing?
        
       | beginnings wrote:
       | give us one free miracle and we'll explain the rest
        
         | downboots wrote:
         | Bertrand Russell is the pope
        
       | Fire-Dragon-DoL wrote:
       | Do we live inside a black hole?
        
       | hulitu wrote:
       | > Research suggests Big Bang may have taken place inside a black
       | hole
       | 
       | Is this OnlyFans ?
        
       | lutusp wrote:
       | > Research suggests Big Bang may have taken place inside a black
       | hole
       | 
       | The title's use of the word "research," and the paper's content,
       | suggest the idea resembles science more than speculation. But in
       | fact, the paper has no observational evidence, nor a proposal for
       | acquiring evidence, to distinguish it from other similar
       | speculations.
       | 
       | To put it simply, at the center of a black hole is a singularity,
       | a domain where existing theories can offer no guidance. So a new
       | idea about singularities -- about black holes -- should suggest a
       | testable property, to distinguish it from other similar ideas.
       | 
       | I say "idea" here to avoid use of the term "theory," which in
       | science requires observational evidence to move past the realm of
       | speculation.
       | 
       | Don't get me wrong -- speculations have an important role to play
       | in science. But tendentious phrases like "research suggests"
       | wrongly imply the presence of something more than speculation.
        
       | whatever1 wrote:
       | So, the whole thing is a recursion, and the only thing left to
       | see is how deep is the stack.
        
       | Aardwolf wrote:
       | Wouldn't it have to be a black hole anyway given how much matter
       | was concentrated in a small point?
        
       | Valgrim wrote:
       | A few years ago a popular idea was that our universe existed as
       | an hologram on the surface of a black hole.
       | 
       | Recently I saw also a theory that black hole might not, in fact,
       | exist as we thought, and may be instead something called
       | 'gravastars', where large stars do not collapse in an infinite
       | point but instead the mass reaches a maximum density and hardness
       | and become sorts of empty bubbles.
       | 
       | Now this. It's not exactly a new idea, I remember reading about
       | black hole cosmology 10 years ago.
       | 
       | Sooo... My uneducated, pop-sci fueled imagination now sees the
       | universe as a mathematical function of a fractal looking like a
       | shell with patterns on it, and those patterns interact or 'fold'
       | in a way where the patterns themselves can be thought of as
       | shells with patterns on them, and each shell creates something
       | that, from the inside, looks like a new dimension of space or
       | time, and what we think of as black holes are the next fold. Does
       | that make sense?
        
         | maaaaattttt wrote:
         | It makes sense to me... I think. And I like this vision as
         | well. It would explain the big bang (initial black hole
         | formation), why the universe is expending (at probably non
         | constant rates over time) which would be the black hole
         | "ingesting" matter and growing and maybe also why time and
         | space are one. Same as you, a take from complete uneducated
         | pop-sci fueled imagination.
        
       | purpleidea wrote:
       | I always pondered about everything in our universe getting
       | swallowed up continuously merging black holes until all of a
       | sudden "everything" is "in" the black hole and then suddenly
       | that's your big bang, and everything starts all over.
       | 
       | I don't have the Ph.D physics/maths skills to work out the
       | plausibility of any of that (or variations on that) but I've
       | always felt I've been good at coming up with ideas.
       | 
       | Any physicist wants to work with me, I'm
       | https://purpleidea.com/contact/
        
       | misja111 wrote:
       | > But how come Penrose's theorems forbid out such outcomes? It's
       | all down to a rule called the quantum exclusion principle, which
       | states that no two identical particles known as fermions can
       | occupy the same quantum state (such as angular momentum, or
       | "spin").
       | 
       | > And we show that this rule prevents the particles in the
       | collapsing matter from being squeezed indefinitely. As a result,
       | the collapse halts and reverses. The bounce is not only possible
       | - it's inevitable under the right conditions.
       | 
       | Do I understand right, that this would mean that every formation
       | of a black hole would result in a bounce?
        
       | scotty79 wrote:
       | I've heard about interesting theory. Since we observe large early
       | galaxies, to explain them scientists postulate that they must
       | have grown very quickly. But recently some scientists calculated
       | how much light would such quickly growing galaxies could have
       | emitted. And it turned out that this light after being dispersed
       | by the dust and redshifted by the expansion of the universe it
       | should have contribute to CMB, up to 100% of it's observed
       | intensity. What's interesting they didn't make any assumptions
       | outside of established modern cosmology. Just So it's entirely
       | possible that CMB is something completely different than what we
       | believed.
        
       | rednik06 wrote:
       | More info available.
       | 
       | TARS is a new theoretical framework that fundamentally reimagines
       | the foundations of physics. Instead of assuming that reality is
       | made of pre-existing entities (particles, fields, or spacetime
       | itself), TARS posits that everything that exists is, at root, a
       | relation. In this view, the universe is a dynamic network of
       | coherence relations, and what we perceive as space, time, matter,
       | and even physical laws, are emergent phenomena arising from this
       | underlying relational web.
       | 
       | 1. Motivation: The Crisis in Fundamental Physics
       | 
       | Modern physics, despite its immense successes, faces deep
       | unresolved problems:
       | 
       | The incompatibility between General Relativity (GR) and Quantum
       | Field Theory (QFT)--the so-called "quantum gravity problem."
       | 
       | The mystery of singularities (in black holes and at the Big
       | Bang), the nature of time, and the unexplained phenomena of dark
       | matter and dark energy.
       | 
       | The lack of a unifying principle that can reconcile the
       | fragmented domains of current theories.
       | 
       | TARS responds to these challenges by proposing a radical
       | ontological shift: relations, not entities, are fundamental. This
       | shift is not just a new model, but a new grammar for describing
       | reality.
       | 
       | 2. Ontological Foundations: Radical Relationalism
       | 
       | Core Postulate:
       | 
       | "All that exists is relation."
       | 
       | There are no absolute, isolated objects. The very identity of any
       | "entity" (particle, field, law) is defined by its pattern of
       | relations with all others.
       | 
       | The universe is fundamentally non-separable: no part can be fully
       | understood in isolation.
       | 
       | This principle generalizes quantum entanglement to a universal
       | ontological status.
       | 
       | Realism and Symbiosis
       | 
       | Symbiotic Realism: Entities and their properties are co-
       | constituted through mutual relations. There are no intrinsic
       | properties, only extrinsic, dynamically co-created ones.
       | 
       | The observer is not external, but an active node in the
       | relational web. Knowledge itself is a process of coherent
       | participation in this network.
       | 
       | 3. Mathematical Formalism
       | 
       | 3.1. From Discrete Relations to Emergent Fields
       | 
       | At the most fundamental level, reality consists of discrete
       | coherence relations, denoted x_{ij} (or quantum operators
       | x_{ij}), between abstract nodes.
       | 
       | At emergent scales, these relations manifest as a continuous
       | coherence field ph_{mn}(x), a symmetric tensor field encoding the
       | density and structure of relational coherence at each emergent
       | spacetime point.
       | 
       | The emergent metric is given by: g_{mn}(ph) = e^{2aph} e_{mn}
       | 
       | The Symbiotic Action is:
       | 
       | S[ph]=[?]d4x-g(ph)[12gmn(ph)([?]mph)([?]nph)-V(ph)]S[ph]=[?]d4x-g
       | (ph)[21gmn(ph)([?]mph)([?]nph)-V(ph)]
       | 
       | where V(ph) is the relational potential.
       | 
       | 3.2. Dynamics: Coherence, Dissonance, and Self-Organization
       | 
       | Local coherence (x_l) and global coherence (x_c) quantify the
       | degree of relational compatibility.
       | 
       | The difference Dx = |x_c - x_l| acts as a "relational tension,"
       | driving the system toward higher global coherence.
       | 
       | When Dx exceeds a threshold, critical reorganizations occur
       | (mediated by an operator F0), leading to emergent order, the
       | arrow of time, and the formation of physical laws.
       | 
       | 3.3. Quantization and Emergence
       | 
       | TARS aspires to a quantum theory of relational fields, where
       | quantization applies to the relations themselves, not to fields
       | on a pre-existing spacetime.
       | 
       | The challenge is to mathematically derive how spacetime, matter,
       | and interactions emerge from the dynamics of x_{ij}.
       | 
       | 4. Phenomenological Implications
       | 
       | TARS provides new perspectives and solutions to major physical
       | puzzles:
       | 
       | Singularity Resolution: The regularization of black hole and
       | cosmological singularities emerges naturally from the relational
       | dynamics.
       | 
       | Dark Matter/Energy: Gravitational anomalies are interpreted as
       | regions of relational coherence deficit, not as unseen particles.
       | 
       | Inflation and Cosmology: The early universe's rapid expansion is
       | modeled as a phase transition in the global coherence field.
       | 
       | Black Hole Evaporation: Predicts a slower, non-singular
       | evaporation process, leaving stable remnants.
       | 
       | Consciousness and Life: Interpreted as high-order reflexivity in
       | relational networks--consciousness is a self-referential
       | coherence loop.
       | 
       | 5. Scientific Achievements to Date
       | 
       | Full mathematical formalism: Action, field equations, emergent
       | metric, and relational potentials.
       | 
       | Analytical derivations: For black hole interiors, dark matter
       | effects, and cosmic inflation.
       | 
       | Numerical simulations: Demonstrating the propagation of coherence
       | fronts and self-organization.
       | 
       | Distinct predictions: Such as black hole evaporation profiles and
       | singularity avoidance, differentiating TARS from standard models.
       | 
       | White paper and technical documentation: Comprehensive and
       | available for peer review.
       | 
       | 6. Meta-Theoretical and Interdisciplinary Reach
       | 
       | TARS is not just a new physical theory; it is a meta-framework
       | for understanding emergence, organization, and knowledge itself.
       | Its principles can be applied to biology, neuroscience, social
       | systems, and artificial intelligence, wherever complex relational
       | networks give rise to emergent phenomena.
       | 
       | 7. Conclusion
       | 
       | TARS offers a radical, mathematically grounded, and
       | phenomenologically rich alternative to current foundational
       | physics. By shifting the focus from entities to relations, it
       | provides a unified language for the emergence of space, time,
       | matter, and law. Its predictions are testable, its formalism is
       | rigorous, and its implications reach far beyond physics, offering
       | a new way to organize scientific and philosophical knowledge.
        
       | rednik06 wrote:
       | TARS is a new theoretical framework that fundamentally reimagines
       | the foundations of physics. Instead of assuming that reality is
       | made of pre-existing entities (particles, fields, or spacetime
       | itself), TARS posits that everything that exists is, at root, a
       | relation. In this view, the universe is a dynamic network of
       | coherence relations, and what we perceive as space, time, matter,
       | and even physical laws, are emergent phenomena arising from this
       | underlying relational web.
       | 
       | 1. Motivation: The Crisis in Fundamental Physics
       | 
       | Modern physics, despite its immense successes, faces deep
       | unresolved problems:
       | 
       | The incompatibility between General Relativity (GR) and Quantum
       | Field Theory (QFT)--the so-called "quantum gravity problem."
       | 
       | The mystery of singularities (in black holes and at the Big
       | Bang), the nature of time, and the unexplained phenomena of dark
       | matter and dark energy.
       | 
       | The lack of a unifying principle that can reconcile the
       | fragmented domains of current theories.
       | 
       | TARS responds to these challenges by proposing a radical
       | ontological shift: relations, not entities, are fundamental. This
       | shift is not just a new model, but a new grammar for describing
       | reality.
       | 
       | 2. Ontological Foundations: Radical Relationalism
       | 
       | Core Postulate:
       | 
       | "All that exists is relation."
       | 
       | There are no absolute, isolated objects. The very identity of any
       | "entity" (particle, field, law) is defined by its pattern of
       | relations with all others.
       | 
       | The universe is fundamentally non-separable: no part can be fully
       | understood in isolation.
       | 
       | This principle generalizes quantum entanglement to a universal
       | ontological status.
       | 
       | Realism and Symbiosis
       | 
       | Symbiotic Realism: Entities and their properties are co-
       | constituted through mutual relations. There are no intrinsic
       | properties, only extrinsic, dynamically co-created ones.
       | 
       | The observer is not external, but an active node in the
       | relational web. Knowledge itself is a process of coherent
       | participation in this network.
       | 
       | 3. Mathematical Formalism
       | 
       | 3.1. From Discrete Relations to Emergent Fields
       | 
       | At the most fundamental level, reality consists of discrete
       | coherence relations, denoted x_{ij} (or quantum operators
       | x_{ij}), between abstract nodes.
       | 
       | At emergent scales, these relations manifest as a continuous
       | coherence field ph_{mn}(x), a symmetric tensor field encoding the
       | density and structure of relational coherence at each emergent
       | spacetime point.
       | 
       | The emergent metric is given by: g_{mn}(ph) = e^{2aph} e_{mn}
       | 
       | The Symbiotic Action is:
       | 
       | S[ph]=[?]d4x-g(ph)[12gmn(ph)([?]mph)([?]nph)-V(ph)]S[ph]=[?]d4x-g
       | (ph)[21gmn(ph)([?]mph)([?]nph)-V(ph)]
       | 
       | where V(ph) is the relational potential.
       | 
       | 3.2. Dynamics: Coherence, Dissonance, and Self-Organization
       | 
       | Local coherence (x_l) and global coherence (x_c) quantify the
       | degree of relational compatibility.
       | 
       | The difference Dx = |x_c - x_l| acts as a "relational tension,"
       | driving the system toward higher global coherence.
       | 
       | When Dx exceeds a threshold, critical reorganizations occur
       | (mediated by an operator F0), leading to emergent order, the
       | arrow of time, and the formation of physical laws.
       | 
       | 3.3. Quantization and Emergence
       | 
       | TARS aspires to a quantum theory of relational fields, where
       | quantization applies to the relations themselves, not to fields
       | on a pre-existing spacetime.
       | 
       | The challenge is to mathematically derive how spacetime, matter,
       | and interactions emerge from the dynamics of x_{ij}.
       | 
       | 4. Phenomenological Implications
       | 
       | TARS provides new perspectives and solutions to major physical
       | puzzles:
       | 
       | Singularity Resolution: The regularization of black hole and
       | cosmological singularities emerges naturally from the relational
       | dynamics.
       | 
       | Dark Matter/Energy: Gravitational anomalies are interpreted as
       | regions of relational coherence deficit, not as unseen particles.
       | 
       | Inflation and Cosmology: The early universe's rapid expansion is
       | modeled as a phase transition in the global coherence field.
       | 
       | Black Hole Evaporation: Predicts a slower, non-singular
       | evaporation process, leaving stable remnants.
       | 
       | Consciousness and Life: Interpreted as high-order reflexivity in
       | relational networks--consciousness is a self-referential
       | coherence loop.
       | 
       | 5. Scientific Achievements to Date
       | 
       | Full mathematical formalism: Action, field equations, emergent
       | metric, and relational potentials.
       | 
       | Analytical derivations: For black hole interiors, dark matter
       | effects, and cosmic inflation.
       | 
       | Numerical simulations: Demonstrating the propagation of coherence
       | fronts and self-organization.
       | 
       | Distinct predictions: Such as black hole evaporation profiles and
       | singularity avoidance, differentiating TARS from standard models.
       | 
       | White paper and technical documentation: Comprehensive and
       | available for peer review.
       | 
       | 6. Meta-Theoretical and Interdisciplinary Reach
       | 
       | TARS is not just a new physical theory; it is a meta-framework
       | for understanding emergence, organization, and knowledge itself.
       | Its principles can be applied to biology, neuroscience, social
       | systems, and artificial intelligence, wherever complex relational
       | networks give rise to emergent phenomena.
       | 
       | 7. Conclusion
       | 
       | TARS offers a radical, mathematically grounded, and
       | phenomenologically rich alternative to current foundational
       | physics. By shifting the focus from entities to relations, it
       | provides a unified language for the emergence of space, time,
       | matter, and law. Its predictions are testable, its formalism is
       | rigorous, and its implications reach far beyond physics, offering
       | a new way to organize scientific and philosophical knowledge.
        
       | tekkk wrote:
       | Interesting sci-fi plot device but seems far-fetched, not gonna
       | lie. To think that our highly stable universe is just compressed
       | mass of another universe is a lot to take in. Does that black
       | hole emit Hawking radiation as well and shouldnt our universe
       | lose mass in result? And how exactly can our universe expand if
       | the size of the black hole is fixed?
       | 
       | Well, at least it does make for interesting conversations.
       | Someone will surely milk it for Youtube content.
        
       | ordu wrote:
       | Hmm... What if some matter falls into our black hole? I know
       | there are some weird time-space effects on the boundary, which I
       | do not have any intuition about. To my knowledge it may be, that
       | it will never fall in our time frame, or that it have fallen all
       | already. The question is, will we able to see and welcome new
       | matter entering our Universe?
        
         | rokobobo wrote:
         | I may be wrong, but I believe spending time in a deeper
         | gravitational well means you observe everything outside of the
         | well to be happening much faster; at the singularity, the
         | entire future of the parent universe will appear to you as
         | happening all at once. There is no notion of "matter that falls
         | in later" -- once you reach the singularity, you travel to the
         | end of time in the parent universe. And the passage of time in
         | our universe isn't a continuation of time in the parent
         | universe; it's not even the same dimension, the latter is
         | collapsed.
        
           | giorgioz wrote:
           | Thank you! That answered my question whether there would be
           | in our universe a "white fountain" spitting matter coming
           | from the back hole in the top universe. In your hypothesis
           | where we lose one dimensione over the top universe than all
           | the events of the top universe, like the mass arriving,
           | happen in our universe all at the once in the beginning (the
           | big bang).
        
       | dinkblam wrote:
       | stupid question: if at the beginning of the universe (before the
       | big bang) all the matter was in the very same spot, shouldn't
       | this have been effectively been a black hole due to the extreme
       | density? if so, how could it explode if nothing can escape a
       | black hole?
        
         | anonymous_sorry wrote:
         | That's not a stupid question. But I suggest reading the linked
         | article which pretty much covers this.
        
         | oneshtein wrote:
         | Black holes may contain a second event horizon in the center,
         | like a Poisson's spot. So it was the Big Rip, when this spot
         | was born.
        
       | kosh2 wrote:
       | I have two problems / questions with this:
       | 
       | 1. This theory requires a parent universe that can't have been
       | formed inside a black hole. This means there must a be second
       | "universe creation" mechanism that we can / may never know about
       | from our child universe. For me, this doesn't really answer the
       | true question: "How did our universe begin?" Yeah, it may the
       | "unknown field with strange properties" but instead we get an
       | unknown parent universe with strange properties.
       | 
       | 2. The black hole in the parent universe must be much much bigger
       | than anything we see in ours since it has to contain all the
       | matter that we see. How is a black hole supposed to form that is
       | 750 billion times bigger than the largest black hole we know
       | about?
        
         | bagacrap wrote:
         | Wouldn't every theory/model of the universe leave room for
         | follow up questions? Why is it problematic if it doesn't answer
         | literally every conceivable quandary?
        
         | godelski wrote:
         | > requires a parent universe
         | 
         | Not _exactly_. A universe can expand, slow down, then collapse.
         | In this case, bouncing back out.
         | 
         | Does that repeat forever? Does it lose energy in the bounce? If
         | so, to where and how?                 > The black hole in the
         | parent universe must be much much bigger than anything we see
         | in ours
         | 
         | Yes and no. You're not thinking about contraction. With
         | relativity we can fit a 100ft ladder inside a 10ft barn.
         | 
         | Most importantly, you don't need everything all figured out at
         | once to publish. Then no one would always publish. There'd be
         | nothing to improve on. Only one publication that says
         | everything. Till then, everything does have criticisms and is
         | incomplete. It's good to have criticisms! They lead you to the
         | next work!
        
           | 2OEH8eoCRo0 wrote:
           | Where does the information of the previous universe before
           | the bounce go? Is it destroyed?
        
             | JKCalhoun wrote:
             | It's been suggested it is gone and that perhaps even new
             | laws of physics are created with each iteration (but I
             | don't know why that would be).
        
             | mordae wrote:
             | Maybe we live inside an universal hash function.
        
           | mcswell wrote:
           | >> The black hole in the parent universe must be much much
           | bigger than >> anything we see in ours
           | 
           | >> Yes and no. You're not thinking about contraction. With
           | relativity >> we can fit a 100ft ladder inside a 10ft barn.
           | 
           | I believe the OP was talking about mass, not linear
           | dimension. (And if he wasn't, I am.) Unless somehow mass
           | inside a black hole is not constant? (ignoring accretion)
        
         | meowky wrote:
         | 1. It is _possible_ that every universe is formed in a
         | blackhole - an infinite universe-blackhole-universe chain. We
         | don't know what "infinity" means in this scenario, so we can't
         | simply rule it out. For comparison, Aristotle ruled out an
         | infinite chain of _causes_ , which we now know (with the help
         | of hindsight, of course) is a flawed conclusion.
         | 
         | 2. We don't know whether our universe is big or small compared
         | with other universes. We don't know whether, or how, it makes
         | sense to compare sizes between universes.
         | 
         | Big Bang is arguably the biggest speculation in modern science.
        
         | PaulHoule wrote:
         | I don't see this idea as very new.
         | 
         | There are many models of black holes, such as the Schwarzchild
         | solution, that have an area of "asymptotically flat spacetime"
         | which is, from the viewpoint of our universe, part of the black
         | hole. That something happens around the singularity that
         | creates this new universe doesn't sound that crazy.
         | 
         | If our universe is a child of another universe and that is a
         | child of another universe and so forth it fits into the kind of
         | "multiverse" model that addresses issues such as "why does the
         | universe have the parameters it does?" Either there are a huge
         | amount of universes such that we're lucky to be in one we can
         | live in, or there is some kind of natural selection such that
         | universes that create more black holes have more children.
         | 
         | As for the relative size of the parent black hole, conservation
         | of energy doesn't have to hold for universes in the normal
         | sense. One idea is that the gravitational binding energy of the
         | universe is equal to the opposite of all the mass in the
         | universe such that it all adds up to zero so we could have more
         | or less of it without violating anything.
        
           | nurettin wrote:
           | > "why does the universe have the parameters it does?"
           | 
           | To those who say "oh but if this parameter was slightly off,
           | that thing I subjectively decided to pick wouldn't have
           | happened!":
           | 
           | How would you know that this universe could exist in any
           | other way? Wouldn't things just stabilize into certain
           | frequencies and lengths after some time?
           | 
           | To me "fine tuning" isn't really a conundrum, it is just
           | question begging and you don't need to wish it away with
           | multiverses.
        
           | D-Coder wrote:
           | > we're lucky to be in one we can live in
           | 
           | Nitpick: We _couldn 't_ be anywhere else, except nonexistent.
        
             | thomasweiser wrote:
             | The anthropic principle
        
           | corry wrote:
           | Do you find the idea of an infinite regress -- "our universe
           | is a child of another universe and that is a child of another
           | universe and so forth" -- holds much explanatory power for
           | you?
           | 
           | To me it's prima facie a hollow explanation. I get that some
           | models, like eternal inflation or certain cyclic cosmologies,
           | entertain the idea of an infinite past or blur the standard
           | arrow of time... but how does pushing the origin question
           | back indefinitely actually resolve anything?
        
             | lugu wrote:
             | I doubt you understand what science is about. The proposed
             | theory, like any theory, should be judged on its power of
             | prediction and simplicity. It doesn't matter if it doesn't
             | satisfy your curiosity.
        
         | bhk wrote:
         | It's black holes all the way down!
        
         | mr_toad wrote:
         | The outer universe could have always existed, but unlike ours
         | it eventually collapsed. By contrast ours did the reverse, and
         | it looks like it will expand forever. There is a neat symmetry.
         | I guess you could make the case that it's really just one
         | universe, and the collapse and expansion mirror each other.
        
         | nbulka wrote:
         | We think the universe had to "begin" because we "began" and
         | tend to anthropomorphize. Is that necessarily true? The
         | universe is under no obligation to have a beginning. Sail
         | around the Earth and you might just end up right where you
         | started.
        
           | mc32 wrote:
           | The Sun had to begin. At one point it was just accreting
           | gasses, then at some point gained enough mass to ignite.
           | People also start at some point they begin as a daughter and
           | grow eventually into a viable life. But also our galaxies had
           | to form before our sun. So, yes there are beginnings to
           | things. At one point they weren't, at another point they
           | were.
        
           | jungturk wrote:
           | Yes, but earth still had a beginning.
           | 
           | I agree with you, though - causal explanations are compelling
           | and confer a sense of certainty and humans seem to like that,
           | but it doesn't make them necessary.
        
       | 0x0203 wrote:
       | If the universe does have a positive curvature as this predicts,
       | would that mean that if we look out into space, we could see the
       | same galaxies multiple times? Or even our own galaxy in the past?
       | Or is the predicted curvature slight enough that anything we
       | might see multiple times is already beyond the limits of
       | visibility due to universe expansion?
        
         | mr_toad wrote:
         | Only if the circumference of the universe is small enough for
         | light to have made the round trip since the universe began. But
         | we think that the universe is much larger than that.
         | 
         | https://en.wikipedia.org/wiki/Particle_horizon
        
       | okokwhatever wrote:
       | Science today:
       | 
       | {..insert here a statement...} maybe yes but also maybe not
       | {...clickbait things here...}
        
       | ddingus wrote:
       | Great! Maybe the idea of a cyclical universe will gain traction.
       | 
       | In my view, there is one universe. We are in it. It cycles from
       | maximum to minimum condition endlessly. This cycle is much longer
       | than any entity lifespan and for any entity, the current state is
       | THE state for them, and all they will know and become.
       | 
       | What does it expand into?
       | 
       | Nothing. Space itself just gets bigger and smaller over time.
       | 
       | No beginning, no end. It all just is.
        
       | andreygrehov wrote:
       | We are inside of a Docker container.
        
       | joshdavham wrote:
       | Would it possibly make sense for a black hole in our universe to
       | lead to a higher level "parent" universe? Or would any black hole
       | universe contained within our own universe necessarily lead to a
       | lower level "child" universe? Basically, I'm wondering if there's
       | a way (within the constraints of this model) to access the parent
       | universe.
        
       | w10-1 wrote:
       | As a lay reader, it sounds like they are assuming what they are
       | trying to prove.
       | 
       | Yes, it produces a testable prediction, but seemingly based on a
       | mathematical assumption derived from our observed cosmic
       | radiation background.
       | 
       | > This lower bound follows from the requirement of
       | khk>=kh*[?]15.9 Gpc to address the cosmic microwave background
       | low quadrupole anomaly
       | 
       | As a lay reader, can I assume that no scientist would publish a
       | theory with mathematical circularity (at the heart of the
       | prediction)? I sure can't verify it myself.
        
       | grumple wrote:
       | I've spent the past month or so immersed in Penrose diagrams.
       | Some of the implications of the math and diagrams include white
       | holes (opposite of black holes - spew matter outwards), infinite
       | universes contained within one another other, anti-gravity
       | universes, and things like this. You can also fall into a black
       | hole and make it out into another universe instead of meeting the
       | singularity (at least, an idealized, rotating black hole).
       | Anyway, cool stuff.
        
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       (page generated 2025-06-12 23:01 UTC)