[HN Gopher] On the Nature of Time
___________________________________________________________________
On the Nature of Time
Author : iamwil
Score : 341 points
Date : 2024-10-08 22:42 UTC (1 days ago)
(HTM) web link (writings.stephenwolfram.com)
(TXT) w3m dump (writings.stephenwolfram.com)
| worstspotgain wrote:
| Thought experiment on the nature of reality:
|
| - In a much larger universe, write down in a log book every event
| to every particle at every instant, from the Big Bang to the
| restaurant.
|
| - Put it on the fireplace mantle and leave it there.
|
| This is basically a log of a simulation. It exists in much the
| same way as an ongoing simulation would, except that its time
| dimension isn't shared with the simulating universe. But every
| observer within has had the same observations as if it did.
| skissane wrote:
| This assumes that a map, if sufficiently detailed, is identical
| to the territory.
|
| Maybe it is, maybe it isn't - but it is a highly debatable
| metaphysical assumption. I'm not sure how seriously we should
| take some people's claims that they "know" that such an
| assumption is actually true
| worstspotgain wrote:
| It's an argument about simulations, not about reality. If
| reality is a simulation, then arguments about simulations
| apply to it, but that's the big if.
| mistermann wrote:
| The word "simulation" is it self a simulation. So is the
| word "is".
|
| https://en.m.wikipedia.org/wiki/Semiotics
|
| Reality is a multi-disciplinary domain, but it gives off
| the appearance of being physics only, because of its
| metaphysical nature.
| skissane wrote:
| Not necessarily. Suppose that consciousness/qualia/etc is
| "something extra" which has to be added to non-mental
| reality, as some dualists believe. Then, it would be
| possible that we live in a simulation which contains
| consciousness because that "something extra" has somehow
| been added to it. And yet, maybe the "much larger" universe
| which contains our simulation also contains such a "log
| book" of a very similar universe to our own, also
| containing intelligent life - and yet, if the "something
| extra" has not been added to that "log book", it would lack
| consciousness and qualia, unlike our own universe.
|
| I'm not arguing that a dualism (of this sort) is actually
| true, merely that we don't (and can't) know for a fact that
| it is false. But if we can't know for a fact that it is
| false, then even if we (somehow) knew our reality was
| simulated, that wouldn't give us grounds to make confident
| inferences about the nature of _other_ simulations, or the
| nature of simulations in themselves
| worstspotgain wrote:
| I agree with your post. However, I was using the most
| mechanical meaning of simulation: "the production of a
| computer model of something, especially for the purpose
| of study," which implies determinism and excludes the
| "something extra."
| skissane wrote:
| It doesn't actually exclude the "something extra", it is
| neutral as to whether or not there is any "something
| extra"
|
| Panpsychists claim _everything_ is conscious, even rocks,
| even atoms. Again, I don't claim this is true (I'd be
| rather shocked if I somehow found out it was), but we
| can't know for a fact that it is false. Yet if
| panpsychism (or at least certain versions thereof) is
| true, every simulation (even a simulation of the weather,
| or of crop growth) is conscious, simply because
| absolutely everything is. But I don't think most standard
| definitions of "simulation" are excluding that
| possibility - on the contrary, they are agnostic with
| respect to it, treating its truth or falsehood as outside
| of their scope
|
| It also doesn't necessarily imply determinism because
| some computer simulations use RNGs. Most commonly people
| use pseudorandom RNGs for this, but there is nothing in
| principle stopping someone from replacing the
| pseudorandom RNG with a hardware RNG based on some
| quantum mechanical process, such that it is
| indeterministic for all practical purposes, and the
| question of whether it is ultimately deterministic or
| indeterministic depends on controversial questions about
| QM to which nobody knows the answers
| worstspotgain wrote:
| > It doesn't actually exclude the "something extra", it
| is neutral as to whether or not there is any "something
| extra"
|
| Roger, that's even better. I tried to clarify the log
| book idea in another reply.[1] The question is whether
| you can have reality (from the observer's perspective)
| just based on whether coherent information exists in
| _any_ setting.
|
| Basically the question is whether we can go from "I
| think, therefore I am" to "something is constructing
| information." The latter is obviously a simpler, lower-
| level proof than other concepts of existence.
|
| That brings us back to the "something extra." Is it
| required for our observations to be possible, i.e. can we
| rule out the log book conjecture? I don't think we can,
| but I might be wrong.
|
| [1] https://news.ycombinator.com/item?id=41783599
| orangecat wrote:
| _And yet, maybe the "much larger" universe which contains
| our simulation also contains such a "log book" of a very
| similar universe to our own, also containing intelligent
| life - and yet, if the "something extra" has not been
| added to that "log book", it would lack consciousness and
| qualia, unlike our own universe._
|
| In that case, the non-conscious people in the log book
| would spend a lot of time pontificating on their
| experiences of consciousness and how mysterious it is and
| whether it's possible for there to be other universes
| that contain entities like themselves except not
| conscious. They'd be having these discussions for reasons
| that have nothing to do with actually being conscious,
| but coincidentally their statements would perfectly
| correspond with our actual perceptions of consciousness.
| Maybe not logically impossible, but it seems extremely
| improbable.
|
| (This is pretty much the argument at https://www.lesswron
| g.com/posts/fdEWWr8St59bXLbQr/zombies-zo... which I find
| persuasive).
| FrustratedMonky wrote:
| Except for the randomness introduced in Quantum Mechanics.
|
| If they ever solve the randomness, then if the map is down to
| every particle, then yes, the map and reality could be the
| same. But think at that point you need a computer the size of
| reality to keep track of every particle.
|
| Or, maybe the entire universe is one giant wave equation. But
| again, I think you need a computer the size of the universe
| to solve it.
| worstspotgain wrote:
| Are you saying that some things are just not simulable,
| given a sufficiently large and powerful computer, or that
| the universe is or might be infinite?
| FrustratedMonky wrote:
| If the universe is real, not simulation.
|
| If you know the position and speed, everything, about
| every particle, then you should be able to extrapolate
| the future by calculating it. The problem is you need a
| computer the size of the universe to do that calculation.
|
| So even thought the map is the territory, equal scale,
| and you have the map. It is little worthless because the
| map ends up being reality.
|
| Edit: Little different than the idea that if this is
| simulation, you can do clipping and only render what we
| see. I'm saying the entire universe is 'real'.
| tines wrote:
| > If you know the position and speed, everything, about
| every particle, then you should be able to extrapolate
| the future by calculating it.
|
| But isn't that the exact thing that quantum mechanics
| refutes? You cannot know the future just from the past;
| you can only know the probabilities of different futures.
| FrustratedMonky wrote:
| Yes. I referred to the randomness that would prevent
| this, "once that is solved".
|
| Guess I'm in the camp that eventually we'll find some
| model or discover something new, to discover what is
| behind the randomness, so it is no longer just random.
| But, yes, that is big IF.
|
| Until then, with current theories, we couldn't do these
| calculations. They'd just be approximations accounting
| for some randomness.
| Filligree wrote:
| Many-Worlds doesn't contain or require any randomness.
|
| I guess for whatever reason you don't consider that to be
| the correct discovery?
| FrustratedMonky wrote:
| Because it doesn't remove the randomness from our
| universe. It punts it to other universes. That is great,
| but doesn't allow us to predict things in our individual
| universe.
|
| Or another way of saying it. We have 2 answers, they are
| determined. That is great, we know the 2 answers, one in
| each universe. Now the problem is we don't know what
| universe we are in. Now which universe we are in is
| random.
|
| We didn't move the ball towards doing something useful in
| our own universe.
| Filligree wrote:
| The 'universes' are loose abstractions, not a defined
| part of the theory; there's no actual hard distinction
| between timelines, in much the same way as coastlines
| don't have a defined length. They all blend into each
| other if you look closely enough.
|
| That said, isn't the obvious answer 'all of them'?
| worstspotgain wrote:
| OK, but if you own the machine, you can just pick the
| outcome you want, or draw it from the distributions at
| random. _We_ (observers inside the machine) cannot know
| the future of course.
| worstspotgain wrote:
| If the universe is not infinite, and if individual
| particles and waves are calculable, it follows that one
| can postulate a larger universe capable of simulating it,
| or a large enough log book in this example.
|
| What I find interesting is looking at whether some
| observable things look like they might be performance
| optimizations, or even "magic seeds" (as in RNG seeds.)
|
| No proof of a simulation obviously, but maybe hints.
| jorvi wrote:
| > The problem is you need a computer the size of the
| universe to do that calculation.
|
| I'm not sure were you get that idea from. The amount of
| calculations we can do, per say, 1 000 000 molecules
| dedicated to the calculation has absolutely skyrocketed,
| and will continue to skyrocket.
| FrustratedMonky wrote:
| "The amount of calculations we can do, per say, 1 000 000
| molecules dedicated to the calculation "
|
| Lets say it takes 100 molecules in a circuit to calculate
| 1 particles state. Then you already would need a universe
| 100X the size to calculate our 1X size universe.
|
| I'm assuming all particles, not that this is somehow
| clipping and only rendering what we see. I'm not talking
| about the brain in box simulation, I'm talking about idea
| that entire universe is out there. What would it take to
| calculate every position of every particle.
| jorvi wrote:
| > Lets say it takes 100 molecules in a circuit to
| calculate 1 particles state. Then you already would need
| a universe 100X the size to calculate our 1X size
| universe.
|
| That's not how it works though. You'd have a lot of fixed
| costs to build a computer that simulates exactly the
| behavior of one particle. But then simulating a secondary
| particle will have a much, much, much smaller marginal
| cost.
|
| Since you brought up clipping, games are actually a
| perfect example. You can see games as very crude
| simulations of our own reality, or slices of it. Take for
| example Red Dead Redemption 2. Run it on a PS5. Now
| compare the size of your PS5 to the mass of what was the
| old Wild West territory :)
|
| Plus there's the whole quantum computing thing, where in
| a way you're reaching into "alternate" realities for
| extra compute.
| FrustratedMonky wrote:
| Yes. Just like a Minecraft World is like the size of
| 64,000 Earths, but it runs on my laptop.
|
| That is what I'm saying is not happening. I'm saying that
| in a particle collider, we measure particles, and those
| exist all the time, not just when we are looking at them.
| Like, I have DNA and bones, they exist all the time, not
| just a simulation showing a 'skin' so it doesn't have to
| render everything.
|
| Unless you are making a bigger point. That a computer
| that could be simulating every single particle, must
| exist outside this universe, and maybe mass and energy in
| this outside universe is so radically different we can't
| even grasp the scales of it.
|
| Just like someone inside a minecraft world with blocks,
| couldn't grasp the amount of energy in our world.
| jorvi wrote:
| Well, I don't know about outside the universe, but you're
| still not understanding how scaling works. And our
| technological progress.
|
| The simplest way I can put it is that at some point of
| compute, there is a crossover where you need less mass to
| simulate something than the mass of the actual thing is.
| This will hold true for particle simulations as well. So
| no, you would not need more particles than the universe
| has to simulate the universe perfectly.
| FrustratedMonky wrote:
| Ok. I'll try again. I think the 'scaling' issue here is
| not understanding the size of the scale if we are talking
| about if dealing with every particle in the universe. The
| largest super computers today aren't simulating every
| particle in even a few molecules.
|
| So lets say you have Minecraft running.
|
| You can completely build a CPU / Memory, etc... Inside
| Minecraft with Redstone.
|
| Lets say you do this, build a PC inside Minecraft to the
| point that it is functional enough to run Minecraft.
| Minecraft running in Minecraft.
|
| There is huge overhead.
|
| You need an astronomically large real PC that could
| handle running Minecraft such that the Minecraft version
| running inside Minecraft is usable. That is the scale
| problem.
|
| I'd have to dig up the citation. But pretty sure this
| compute power needed to compute the universe has been
| worked out.
| skissane wrote:
| We don't know for a fact that QM contains irreducible
| indeterminism. If many worlds is true, then QM is
| ultimately deterministic. Same if hidden variables is true.
| A large class of local hidden variable theories have been
| ruled out by Bell's theorem, but non-local hidden variable
| theories survive it (such as the Bohm interpretation and
| the transactional interpretation), as do local hidden
| variable theories which deny the Bell theorem's assumptions
| about the nature of measurement, such as superdeterminist
| local hidden variable theories.
| goatlover wrote:
| An MWI universe would be hard to simulate though. There's
| an unknown vast number of branches.
| zeven7 wrote:
| Maybe with a quantum computer in a larger multi worlds
| universe?
| FrustratedMonky wrote:
| Wasn't the Noble prize last year for eliminating local
| hidden variables? That spooky action at a distance does
| occur?
|
| And for many worlds. Doesn't it punt randomness into
| other universes, but doesn't help us solve for results in
| our own individual universe. Since we can't measure what
| happens in the other universe we don't really know. If
| there were two results, and one is in one universe, and
| one in our universe, sure we determinedly know both
| results. But we don't know which universe we are in, so
| instead of a random result, now we have 2 answers and 2
| universes, but now randomly don't know where we are?
| kaibee wrote:
| > now we have 2 answers and 2 universes, but now randomly
| don't know where we are?
|
| We are in both. Both universes are equally real. Each
| 'copy' of you knows it's in the universe where the result
| matches the observation.
| FrustratedMonky wrote:
| I'm pretty sure this is not true. Nobody has proven this.
|
| If in my universe I could always predict the correct
| results, then we would just have determinism, and I could
| predict exactly when an atom would decay. There would be
| no need for statistics.
|
| Some high level background that might help.
|
| https://www.youtube.com/watch?v=z-syaCoqkZA
|
| https://www.youtube.com/watch?v=433tAfO4dbA
|
| https://www.youtube.com/watch?v=rvG1A795tqE
| skissane wrote:
| > Wasn't the Noble prize last year for eliminating local
| hidden variables? That spooky action at a distance does
| occur?
|
| The 2022 Nobel Prize in Physics was for experimental
| verification of Bell's theorem. The experiment did not
| rule out superdeterministic local hidden variables;
| superdeterministic local hidden variables does not
| violate Bell's theorem, since Bell's theorem assumes
| "free will" (that there is no correlation between
| arbitrary choices made by an experimenter and the state
| of the system being measured), but superdeterminism is
| the denial of that assumption.
| partomniscient wrote:
| I am King Ozymandias look upon my complete data dump/backup*,
| ye mighty and despair!
|
| *May be subject to entropy over time.
| amelius wrote:
| If I took the binary representation of that log and XOR'ed it
| with a random binary string, then would the result also have
| observers with the same observations?
| worstspotgain wrote:
| Good question? :) I'd say no.
|
| How about an exact copy of the log book, but with one bit
| flipped. Voila, mostly universal physics.
| kouru225 wrote:
| Ok but the act of writing it down would always take longer than
| the actual unfolding of the universe itself. Just like the
| halting problem, we can't skip ahead at any point and we have
| no idea what will come next.
| worstspotgain wrote:
| Sure, but the timebases are different. Maybe it took the
| butterflypeople a thousand butterflyweeks to write it out.
|
| Let me restate the metaphysics a bit differently. Let's say
| there's no us, no butterflypeople, nothing at all. Entropy
| reigns supreme, no information is organized.
|
| Now add the butterflypeople. They write the humanpeople's log
| book. Information exists in organized form. The humanpeople's
| bits have been divined out of the great entropic nothing.
| Maybe that's all it takes?
| garaetjjte wrote:
| Reminds me of https://xkcd.com/505/
| julianeon wrote:
| There's a hidden condition here.
|
| How do you know every event to every particle?
|
| The answer to that will literally change what gets written in
| the log book.
| kridsdale3 wrote:
| The point is the log is a graph or a tree, not an array.
| throw310822 wrote:
| Now shred that log to particles and scatter them everywhere,
| and you have the "dust theory". Neither the time dimension or
| the log are shared with the simulating universe, and yet they
| are still valid for the observers within the universe.
|
| If the sequence of the log states is entirely deterministic
| based on the initial state, then you don't even need to
| actually write down the entire log for it to "exist". This is
| Greg Egan's Permutation City.
| worstspotgain wrote:
| Can we reduce this to an estimate of survivorship bias? If
| there is only one universe, then our survival is clearly
| explained: we're in the only reality there is. If all
| possible universes exist, then we really lucked out in ending
| up in this one (well, depending on who wins the election I
| guess.)
|
| In the middle are the permutations selected through the
| filter of other realities, when they chose which universes to
| simulate. We lucked out but not as much, because
| uninteresting universes never made it out of the entropic
| soup.
|
| It would have to be a conditional estimate of course, because
| our sentience biases our contemplation.
| oersted wrote:
| Quick appreciation for the Douglas Adams reference :)
| buginprod wrote:
| Randall has you covered: https://xkcd.com/505/
| nonameiguess wrote:
| This kind of thought experiment seems like it breaks down due
| to the uncertainty principle. We can't exactly specify the full
| state of every particle in the universe. The universe might
| also be infinite and you can't enumerate an infinite set even
| without uncertainty, though you can write a generating function
| or recurrence relation for it, which seems to be Wolfram's
| point.
|
| But why bother with this kind of detail? What's the difference
| between what you're imagining here and a normal reel of film?
| It can be played back, but even if it isn't, it records the
| state of events that happened, including observers that once
| existed and no longer do, experiencing events that once
| happened but no longer do. It's possible for a record to
| describe a canonical sequence even if the record itself doesn't
| change. Somebody outside of the record can view it out of
| order, speed it up, slow it down, pause it, reverse it. A film
| reel doesn't share the time dimension of its own universe in
| that way.
|
| I'm struggling to come up with what this implies and why.
| worstspotgain wrote:
| To your first point, if it's a simulated universe, the
| simulators can just choose to make it finite, and come up
| with their preferred particle behavior rules.
|
| As observers, we perceive time as passing, but is there
| anything special in this perception? Looked at another way,
| everything could be frozen in a 4D log book and we couldn't
| tell the difference, or could we? In this interpretation,
| Napoleon is as alive (in 1820) as we are (in 2024.) A film
| reel is a similar concept, except it's just a 3D projection
| rather than a complete detailed 4D account.
| nonameiguess wrote:
| I get the questions of eternalism, the reality of the past
| and future, why privilege the present (or at least _my_
| present), and all that. I just don 't understand why the
| fact that you can record events in a medium that doesn't
| experience the time that it records has any implications
| for how we should think about this.
|
| Whether or not you want to say "Napoleon exists" or
| "Napoleon existed" seems to be a matter of linguistic
| convention and the more common latter would reflect
| speakers privileging their own time. If you want to look at
| it another way, Napoleon exists, but entirely in my past
| light cone, and I exist entirely in his future light cone.
| I can't send him any kind of information, but he can send
| information to me. Is there anything special in this
| perception? To who? To observers at the absolute end of all
| time, my future is just as written in stone as Napoleon's.
| To observers I can receive information from, my future is
| unknown.
|
| To any particular observer, there are regions of spacetime
| in which you have no past. There are regions in which you
| have no future. There is a region in which you have both a
| past and a future. Is there anything "special" in
| perceiving the sequence of events within the third region
| as passing rather than existing forever as a log? Not
| really. You're just describing a different variety of the
| Copernican principle or relativity as far as I can tell.
| But so what? None of us are the center of the univers. None
| of us exist in a special inertial frame describing absolute
| spacetime. These facts, however, have consequences in terms
| of how to measure and compute stuff. They change the kind
| of testable predictions you make given certain conditions.
| What computational or predictive consequences arise from
| observing that the entire world curve of the universe
| exists at once from a perspective outside of the universe?
| Going back to the I can't send information to Napoleon
| thing, if observers outside of our universe are keeping a
| log, none of us nor anything else in our universe can
| receive information from them, so what difference does it
| make?
|
| It's an interesting shower thought but kind of also a big
| so what?
| hyperhello wrote:
| Okay. Time is a computation. Patterned or otherwise predictable
| computations can be performed instantly and thus are not time.
| Only results that can't be precomputed are part of our
| perceptions. That's what I got out of it.
| twilo wrote:
| I believe it's simply a unit of measurement we use to understand
| the movement or rhythm on which the universe operates, so it
| could be termed the "progress of computation" if that makes more
| sense but it's all in the same effort.
| lisper wrote:
| I wrote up more or less the same idea ten years ago, but in what
| I think is a more accessible presentation:
|
| https://blog.rongarret.info/2014/10/parallel-universes-and-a...
| WhitneyLand wrote:
| Thank you so much for this.
|
| Whenever people criticize Wolfram the comeback is often, he's
| just trying to discuss big ideas that mainstream science won't
| talk about. Of course that's not the reason for the criticism
| at all and I think your work here shows that it's totally fine
| to speculate and get a little philosophical. The results can be
| interesting and thought provoking.
|
| There's a difference between big ideas and grandiosity. It also
| shows big ideas can stay scientifically grounded and don't
| require making up corny terminology (Ruliad? lol).
| whyenot wrote:
| I have read and appreciated your writings going back to the
| comp.lang.lisp days, but a blog post that starts with "if you
| haven't read the previous post, please do before reading the
| rest of this one" is not what I would consider accessible.
| ...and that previous post then asks the reader to first read a
| paper or watch a video before proceeding. While a decade later
| than what you wrote, Wolfram's article is much more self
| contained and complete.
| Q_is_4_Quantum wrote:
| It is possible to make quantitative statements that I think
| capture many of the intuitions you assert. Here was one
| attempt:
|
| https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.10...
|
| That particular proposal was mathematically wrong for reasons I
| still find physically perplexing (it turns out that for some
| events quantum theory allows for stronger memory records -
| defined via classial mutual information - of entropy decreasing
| events!). A simple example is in here:
| https://arxiv.org/abs/0909.1726 (I am second author).
| lisper wrote:
| Very interesting! Thanks for the pointers! I'll need to take
| some time to digest these.
| ttctciyf wrote:
| It's sort of funny that where the title alludes to the arrow of
| time, opening with a quote asserting "all measurements are in
| principle reversible", it pretty quickly gets to a different
| arrow of time - that of comprehension:
|
| > "If you haven't read the previous post ... this won't make
| any sense"
|
| Could you have demonstrated, perhaps accidentally, an
| alternative organising principle allowing temporal ordering to
| emerge in a computationally oriented ontology? Can the future
| only "make sense" if it temporally follows the past?
|
| Only half kidding!
| lisper wrote:
| That's actually a great question, and one I've been wrestling
| with for years. Why do we perceive time as a sort of
| continuous monotonic flow? And I think it can be explained in
| terms of perception and comprehension, which I have a gut
| feel can be formalized as a kind of preferred basis
| selection. But rendering that intuition into words (and math)
| has turned out to be quite challenging, which I why I haven't
| written about it yet. Maybe in the future :-)
| mistermann wrote:
| > If we were not computationally bounded, we could "perceive the
| whole of the future in one gulp" and we wouldn't need a notion of
| time at all.
|
| Maybe, if we assume we aren't axiomatically bound, despite
| knowing that we are (but that knowledge is rarely in context, so
| we can only know it _sometimes_...once again: time...weird).
|
| "Thought is Time."
|
| - Jiddu Krishnamurti
| downboots wrote:
| > perceive the whole of the future in one gulp
|
| "Therefore, as regards such knowledge, they know all things at
| once" Summa
| Vecr wrote:
| You could perceive (maybe? Depends on how it's hooked up) _a_
| future (a simulation based the information you have), but there
| 's no reason to think that's what the future is with certainty.
| Map/territory stuff too.
| mistermann wrote:
| > but there's no reason
|
| What is it that you refer to here?
| Vecr wrote:
| You can't exactly predict the future unless you have all
| the information, even theoretically.
| mistermann wrote:
| You can certainly predict portions of it (1=1 will
| continue to be true indefinitely, and that's just one
| example).
|
| And, there is no need for predictions to be true, or
| claims of fact about whether there are or are not
| "reasons" for things. In fact, epistemically unsound
| claims such as this are very often the only type of
| speech ~allowed, as crazy as that may seem.
| Vecr wrote:
| I don't see how what you're saying lets you "perceive the
| whole of the future in one gulp", or maybe it does, but
| you can't be confidant that it's the _real_ future.
| drdeca wrote:
| Is any of what he's saying here, something he hasn't essentially
| already said before?
|
| The parts of this which were a little surprising to me (e.g. the
| bit about comparing time to heat, and the bit about running out
| of steps to do at an event horizon) iirc all linked to a thing
| posted a while ago?
|
| I don't share his enthusiasm for the phrase "computational
| irreducibility". I would prefer to talk about e.g. no-speedup
| theorems.
| whatshisface wrote:
| It has been said before, but by Stephen Wolfram.
| ants_everywhere wrote:
| There's "digital physics" which goes back to the late 60s
| https://en.wikipedia.org/wiki/Digital_physics.
|
| The connection between heat/entropy and time is well explored.
| E.g. https://en.wikipedia.org/wiki/Arrow_of_time and
| https://en.wikipedia.org/wiki/Entropy_as_an_arrow_of_time
| nitwit005 wrote:
| It feels like this could be a perfectly decent article if he
| toned down his ego and referenced existing work (other than his
| own).
|
| But I don't think that's possible for him.
| zaptheimpaler wrote:
| I think he's a quack trying to torture an explanation of the
| universe out of his pet theory that uses a lot of words to say
| simple things but doesn't predict anything. If "time is what
| progresses when one applies computational rules" then how is the
| order in which the rules are applied defined in the first place?
|
| Computational irreducibility is a neat idea but i'm not sure its
| novel or something that explains the entire universe. My basic
| intro course on differential equations taught us that the vast
| majority of them cannot be solved analytically, they have to be
| approximated. I don't know if the irreducibility idea is anything
| fundamentally different than saying some problems are hard,
| whether its non analytical equations or NP hard problems.
| kouru225 wrote:
| I think you're slightly misunderstanding his concept of
| computational irreducibility. It's more like the halting
| problem than anything: basically he's saying that dynamic
| systems can't be reduced to an equation that is easier to
| calculate and so you just have to simulate the entire system,
| run it, and watch what happens. This means we can't ever
| predict the future within these systems.
| niobe wrote:
| Well I wouldn't put it quite like that either.. because you
| have to be careful what you mean by 'simulate' and 'easier'.
|
| There could be multiple ways to simulate the same system,
| i.e. produce the same evolutionary output steps. Wolfram
| tends to imply there is only one most-expensive way for
| systems that are computationally irreducible and that way is
| grinding through a recursive computation. I think that's
| partly because the simple experiments, like cellular
| automata, he used to come up with this principle actually
| explore the 'space of simple rules', not the 'space of
| ordered sets of states of systems'.
|
| Of course the latter is a much more computationally expensive
| things to do but it seems to me it would generalise better to
| the universe. Because in the universe what we're really
| observing is the evolution of states not the outputs of
| rules. There may be other hidden assumptions in the principle
| if you assume that all systems can and do evolve from simple
| rules as much of Physics does. Nevertheless, you need a high
| bar if you're going to state universal principles.
|
| Perhaps the simplest way to state the principle is: say we
| set up a simple iterative computation where the input to step
| n, is the output of step n-1. Then there's no way to compute
| state n without having previously computes states n-2, n-3
| etc. That's what he means by irreducible. In other words it's
| "necessarily recursive" which may be a better and more
| focused term.
|
| I'm cautious about making it mean more than that, since
| Wolfram tends to write in great leaps of conclusions without
| showing us his working. Nevertheless I enjoy following his
| ideas, and I did find aspects of this article quite thought
| provoking.
| kouru225 wrote:
| > I think that's partly because the simple experiments,
| like cellular automata, he used to come up with this
| principle actually explore the 'space of simple rules', not
| the 'space of ordered sets of states of systems'.
|
| I think it's the opposite actually. He chose to study these
| recursive systems because they seem to describe reality,
| and then when he found more evidence that they do a good
| job describing reality, he kept studying... so on and so
| forth. Basically a sort of hermeneutic circle type deal.
|
| You do a much more thorough job of describing it. I
| should've mentioned the recursive part earlier. I just
| kinda assume we all already know we're talking about
| recursion and time steps and that's not a useful assumption
| kridsdale3 wrote:
| It's pretty dang hard to give the output to Fibonacci(x)
| for any x up to infinity without having done the work up
| to that point.
| Xcelerate wrote:
| Actually there's an explicit formula for Finonacci(x)
| that involves phi. I think you can use generating
| functions to derive it.
|
| (But your overall point still stands.)
| kouru225 wrote:
| Good point. We're still not describing it perfectly.
| Admittedly I'm doing it by my memory of the last time I
| read Wolframs ideas. I think we unfortunately have to
| describe it using Kolmogorov complexity: what is the
| length of the shortest computer program that produces the
| object as an output? What Wolfram means by computational
| irreducibility is that he asserts that reality itself is
| the shortest length computer program that can produce its
| own output, and it can't be shortened (reduced) any
| further without losing information.
|
| Edit: sorry I think I still haven't fully described it.
| Will have to come back to it tomorrow when I've had some
| sleep
| PaulDavisThe1st wrote:
| Your comment makes me think about statistical mechanics and
| microstates. That is to say ... in a complex system with
| properties that are a function of microstates, whether the
| internal structure of the microstates that correspond to a
| given property matter can depend on your point of view or
| interest in the system.
|
| Heat, for example, is a statistical property of a system,
| and a given temperature can correspond to a vast number of
| possible microstates of the system. For some purposes, you
| care precisely which microstate the system is in; for
| others, you do not, and the temperature property is
| entirely adequate to describe the system.
|
| Rules may describe the microstate, but may be (depending on
| your POV) be irrelevant to the property.
|
| Using Wolfram's model of the world, there may indeed be a
| cellular automata following rules that underlies the
| property, but there may be no reason to care about it in a
| given instance; instead you're interested in the "evolution
| of states" (i.e. values of the property).
|
| Some complexity scientists are quite taken with this idea
| of not needing to care about the lower levels of a system
| when consider higher level behavior. In their view (and
| rightly so, IMO [0]) you don't always need to consider the
| rules that drive (say) physics when considering (say)
| psychology.
|
| [0] except that I think that Hofstadter's "heterarchy" idea
| is likely to be even more accurate - interesting systems
| are the ones in which there are complex feedback systems
| between different levels of the system.
| kridsdale3 wrote:
| It seems pretty clear to me that this desire for
| "perfect" layers of abstraction is something we strive
| for due to our own intellectual limits, and that in
| reality all abstractions are lossy to some degree. Heat
| as a single integer in Degrees F is good enough most of
| the time but when you're designing CVD for a Silicon Fab
| you might actually care about the positions and
| orientations and vectors of the gas molecules.
| sitkack wrote:
| That smells like the Universe is the best Computer for
| computing the future of the Universe tautology.
| kridsdale3 wrote:
| So apparently the inside of the Black Hole event horizon is
| just "Forty Two".
| wizzwizz4 wrote:
| Funny you should say this, because most work on the halting
| problem _is_ reducing the systems down to equations that are
| easier to calculate.
| kridsdale3 wrote:
| But is the theory that such work can continue forever?
| wizzwizz4 wrote:
| There's a point at which it becomes _impossible_ : the
| nth Busy Beaver number is independent of ZF, for n<=745
| (ref: https://wiki.bbchallenge.org/wiki/Cryptids). So no,
| such work cannot continue forever.
|
| We don't know whether such work can continue up to that
| point. The only way to find that out is to explore the
| relevant mathematics, and see if we find something
| fundamentally irreducible. There's no long-term pattern
| to the proofs, despite the presence of short-term
| patterns. (In this sense, the _hunt_ for Busy Beavers is
| computationally irreducible - but there are still easier
| and harder ways of approaching the hunt.)
| sbussard wrote:
| He treats computation as if it is a fundamental law of nature,
| but I don't find that assertion compelling. I'm also more of a
| pilot wave theory advocate, which although incomplete, cuts off
| several diseased (renormalized) branches of quantum physics.
| Trufa wrote:
| I don't mean it as an attack, I honestly mean it as a
| straightforward question, what are your qualifications in this
| matter to call someone as accomplished as SW a quack?
| openrisk wrote:
| Seems like an appropriate post on a day when the Nobel of Physics
| was awarded not for Physics discoveries but for computer
| science...
|
| But from Wheeler's "it from bit" to Wolfram's computational
| universes, the question is: where is the beef.
|
| Now, there might be ultimately something worthwhile with the
| obsession with digi-physics. Mental models that seemed disparate
| may merge and become fruitful. It doesnt even have to be a fully
| formed toolkit. Newton's invention of calculus was kinda sketchy.
| But he was _explaining_ things with it, things that were not
| undestood before.
| WillyWonkaJr wrote:
| Wolfram does offer an interesting alternative to viewing the
| universe as a manifold with a tensor (the GR view). He believes
| it's a graph with computational rules. Are they the same?
| Mathematically, manifolds have a clear notion of dimension.
| This affects things like the inverse square rule. Wolfram's
| view of the ruliad, an evolving graph with rules, does bring up
| the question of dimension.
|
| But at the end of the day he needs to make a concrete
| prediction that differs than the current view in order to have
| people devote a lot of time studying his world view. He's a
| brilliant guy and the Wolfram Language is fantastic, but he
| really needs to humble himself enough to value the work of
| convincing others.
| XorNot wrote:
| Worth noting this is ultimately the problem with string
| theory: String theory does provide a suite of mathematical
| tools which can solve real physics problems and give valid
| answers but they're _known_ physics problems that can also be
| solved with other tools.
|
| To be useful as a theoretical framework it always needed to
| be able to predict something which only string theory could -
| as a "more accurate view of reality".
|
| Which is the same problem here: you've got to make a
| prediction, an accessible prediction, and ideally also not
| introduce any new incompatibilities.
| kridsdale3 wrote:
| I honestly don't think he cares about 'mainstream
| acceptance'. He is a prolific publisher of his detailed
| thoughts, which in the pre-academic-gatekeeping-establishment
| era, was enough for any serious philosopher.
|
| He's a hobbyist. That doesn't make him any less prestigious
| if his ideas are neat.
| openrisk wrote:
| The gatekeeping and manipulation going on in formal
| scientific publishing is notorious, but that is not the
| issue here.
|
| The fundamental algorithm of advancing physical science has
| always been: a set of "principles" or proto-concepts, a set
| of matching mathematical tools (that dont even need to be
| very rigorous), using these tools to explain a slice of
| reality (experimental outcomes) and, finally, predicting
| unknown behaviors that can be sought, can be confirmed (and
| celebrated).
|
| Sometimes even just a purely equivalent mathematical
| representation is fine, as it may give handles for
| calculations and thinking.
|
| But whatever the program with digi-physics is, it doesnt
| follow these age-old patterns that establish validity and
| usefulness intrinsically and not because some gatekeepers
| say so.
|
| The primary utility seems to be to enhance the prestige and
| toolkit of computational physics, which is fine, but
| totally not justifying the universality claims.
| bumbledraven wrote:
| > But at the end of the day he needs to make a concrete
| prediction that differs than the current view in order to
| have people devote a lot of time studying his world view
|
| Even if it doesn't make any different concrete predictions, a
| new way of thinking about things can attract scientists'
| attention. The Many Worlds interpetation of QM is an example.
| lostmsu wrote:
| Discussed in Permutation City
| A_D_E_P_T wrote:
| Yeah. I'm in the middle of writing a book about this, but in a
| sense it was also discussed by the Pythagoreans. And they
| (correctly, I think,) went a step further:
|
| _" The Pythagoreans too used to say that numerically the same
| things occur again and again. It is worth setting down a
| passage from the third book of Eudemus' Physics in which he
| paraphrases their views:_
|
| _'One might wonder-whether or not the same time recurs as some
| say it does. Now we call things 'the same' in different ways:
| things the same in kind plainly recur - e.g. summer and winter
| and the other seasons and periods; again, motions recur the
| same in kind - for the sun completes the solstices and the
| equinoxes and the other movements; But if we are to believe the
| Pythagoreans and hold that things the same in number recur -
| that you will be sitting here and I shall talk to you, holding
| this stick, and so on for everything else - then it is
| plausible that the same time too recurs.'"_
|
| _- Simplicius, Commentary on the Physics 732.23-33._
|
| Branching paths, "all possible mathematics," etc. In a universe
| which appears to be discrete, which can support finitist
| arguments, and where the potential number of paths is starkly
| finite -- this eventually leads to the conclusion that all
| paths eventually recur.
| Filligree wrote:
| Strictly speaking, it only leads to the conclusion that
| eventually the universe will enter a loop passing through a
| finite number of states.
|
| There's no requirement that the current state is part of the
| loop. Or indeed that any state containing conscious observers
| is.
| pizza wrote:
| The bit in Permutation City about siphoning compute by
| exploiting the magnitudes of vector computations as a kind of
| scratch space out of algorithms that only needed the resulting
| angles... wonder if you could modify the DoRA parameter-
| efficient finetuning algorithm to do something like that lol,
| since it also splits up the new weights into angular and
| magnitude components..
| Koshkin wrote:
| I guess I'll just wait for Sabine to say something about this.
| goatlover wrote:
| I'm guessing she'll be pretty sarcastic as she's not overly
| fond of mathematical theories that aren't testable, to say the
| least.
| kgwgk wrote:
| Except for superdeterminism - but maybe she doesn't have a
| choice.
| DiscourseFan wrote:
| Its certainly interesting, though the language its couched in
| wouldn't be found in any philosophical discussion on time. This
| is all to say that it deals with concepts that have been
| discussed in philosophy for a long time, and these insights
| wouldn't be considered "new" to someone from say mid-19th century
| Prussia. Certainly the "progressive unfolding of the truth," in
| qualitatively different steps which Wolfram adopts here as his
| concept of time is no different from Hegel's concept of time and
| the movement of history. I would recommend, for anyone interested
| in this sort of thing, to just read the "Preface" to his
| _Phenomenology of Spirit_.[0]
|
| [0]https://files.libcom.org/files/Georg%20Wilhelm%20Friedrich%2..
| .
| hiddencost wrote:
| I really think that Wolfram's descent into fringe science has
| hurt a lot of well meaning people that don't know better and
| think that because he's developed useful software that he should
| be listened to in these domains.
| XorNot wrote:
| The crackpot trajectory of otherwise smart people is fairly
| well trodden with a number of indicators and nobel laureates
| who have walked it - one of which is when people start stepping
| well outside their field...and then also tend to start stepping
| into "the biggest problems" of wherever they point themselves.
| Mistletoe wrote:
| I call it helicoptering, my old boss used to love to do it.
| Helicopter down onto a problem, act like everyone that
| already studied it was an idiot and hadn't spent their life
| trying to solve X, stir a bunch of dust up, accomplish
| nothing, and helicopter away again to something else.
| qaq wrote:
| Oh maybe because he has a PhD in particle physics from Caltech
| ?
| xanderlewis wrote:
| Eric Weinstein also has a PhD in physics; it doesn't preclude
| you being (or becoming) a crank.
| qaq wrote:
| What is specifically crank about his theory? From outsiders
| perspective having theories that require a bunch of extra
| dimensions just to make the math work sound no less cranky.
| xanderlewis wrote:
| I'm not claiming to be qualified to judge it, but it's
| quite clear that no one who is takes it seriously. He
| also seems to spend most of his time pontificating about
| things he has no expertise in and using his genuine
| expertise in physics to show off in front of easily-
| impressed podcast hosts -- not a great sign.
| qaq wrote:
| " pontificating about things he has no expertise in"
| again he has PhD from Caltech in particle physics he had
| a good number of published works in quantum field theory
| how are you coming to the conclusion he is pontificating
| about things he has no expertise in?
| gammarator wrote:
| It's part of their life cycle https://www.smbc-
| comics.com/comic/2012-03-21
| foundry27 wrote:
| I think it's really interesting to see the similarities between
| what Wolfram is saying and the work of Julian Barbour on time
| being an emergent property. Both suggest a similar underlying
| ontology for the universe: a timeless, all-encompassing realm
| containing all possible states / configurations of everything.
| But what's really fascinating is that they reach this conclusion
| through different implementations of that same interface. Barbour
| talks about a static geometric landscape where time emerges
| objectively from the relational (I won't say causal) structures
| between configurations, independent of any observer. On the other
| hand, Wolfram's idea of the Ruliad is that there's a timeless
| computational structure, but time emerges due to our
| computational limitations as observers navigating this space.
|
| They've both converged on a timeless "foundation" for reality,
| but they're completely opposite in how they explain the emergence
| of time: objective geometry, vs. subjective computational
| experience
| m3kw9 wrote:
| So you are saying there is a version of me that is king of the
| universe in some timeline?
| pixl97 wrote:
| If the universe is infinite then there is a possibility that
| you are a king of an observable universe somewhere.
| xandrius wrote:
| Infinite does not mean that all the permutations are
| possible.
|
| You being you and you becoming a king might simply not be a
| combination which is compatible.
| mensetmanusman wrote:
| You vastly misunderestimate infinity if you don't recognize
| that anything feasible will happen.
| jbotz wrote:
| Depends on how you define feasible.
|
| Take Wolfram's 1-dimensional cellular automata... some of
| them have infinite complexity, and of course you can
| "run" them for infinite time, and the "current" state is
| constantly expanding (like the Universe). So let's define
| "something feasible" as some specific finite bit pattern
| on the 1-dimensional line of an arbitrary current state.
| Is that "feasible" bit pattern guaranteed to appear
| anywhere in the automaton's present or future? I believe,
| and if I understand correctly, so does Wolfram, that for
| any reasonably complex "feasible pattern" the answer is
| no; even though the automaton produces infinitely many
| states, it is not guaranteed to explore all conceivable
| states.
|
| In other words, in a given Universe (which has a specific
| set of rules that govern its evolution in time) even
| though there are infinitely many possible states, not all
| conceivable states are a possible result of that
| evolution.
| mensetmanusman wrote:
| If you exist, you are one of the feasible states.
| pantulis wrote:
| There are infinite numbers between 3 and 4, yet none of
| them is number 7.
| mensetmanusman wrote:
| 7 isn't feasible...
| kridsdale3 wrote:
| Great way to let someone down who asks you out.
|
| There are no branches in the Ruliad in which you and I end
| up together. I have foreseen it.
| grugagag wrote:
| In a skin enclosed universe you are already King Meatbag,
| ruler over your mind and body.
| biofox wrote:
| My body disagrees.
| pizza wrote:
| I was literally thinking of the same similarities. Barbour's
| exposition of the principle of least action as being time is
| interesting. There's a section in The Janus Point where he goes
| into detail about the fact that there are parts of the cosmos
| that (due to cosmic inflation) are farther apart in terms of
| light-years than the universe is old, and growing in separation
| faster than c, meaning that they are forever causally
| separated. There will never be future changes in state from one
| that result in effects in the other. In a way, this also
| relates to computation, maybe akin to some kind of
| undecidability.
|
| Another thing that came to mind when reading the part about how
| "black holes have too high a density of events inside of them
| to do any more computation" is Chaitin's incompleteness
| theorem: if I understand it correctly, that basically says that
| for any formal axiomatic system there is a constant c beyond
| which it's impossible to prove in the formal system that the
| Kolmogorov complexity of a string is greater than c. I get the
| same kind of vibe with that and the thought of the ruliad not
| being able to progressively simulate further states in a black
| hole.
| ziofill wrote:
| Actually, the parts of the universe receding from us faster
| than the speed of light can still be causally connected to
| us. It's a known "paradox" that has the following analogy: an
| ant walks on an elastic band toward us at speed c, and we
| stretch the band away from us by pulling on the far end at a
| speed s > c. Initially the ant despite walking in our
| direction gets farther, but eventually it does reach us (in
| exponential time). The same is true for light coming from
| objects that were receding from us at a speed greater than c
| when they emitted it. See
| https://en.m.wikipedia.org/wiki/Ant_on_a_rubber_rope
| adastra22 wrote:
| They will never reach us because the rate of expansion is
| accelerating.
| ziofill wrote:
| https://arxiv.org/abs/astro-ph/0310808
| adastra22 wrote:
| That article doesn't back up your claim.
| ziofill wrote:
| Yes it does, look at the caption of Fig. 1: "Photons we
| receive that were emitted by objects beyond the Hubble
| sphere were initially receding from us (outward sloping
| lightcone at t <~ 5 Gyr). Only when they passed from the
| region of superluminal recession vrec > c (gray
| crosshatching) to the region of subluminal recession (no
| shading) can the photons approach us".
|
| I can't reply to your last reply. I agree, in fact I said
| those regions _can_ be still causally connected to us,
| not that they are.
| adastra22 wrote:
| It shows that SOME "superluminal" photons can reach us,
| not that ALL can. With accelerating expansion, eventually
| all galaxies fall out of that interval and become
| unreachable.
| nyrikki wrote:
| Those photons aren't superluminal, the are in our past
| light cone, they were headed out way before the emitter
| was beyond the horizon.
|
| It gets complicated because the concept of 'now' is a
| local property and because those objects aren't moving
| away ftl, space is expanding.
| csomar wrote:
| > There will never be future changes in state from one that
| result in effects in the other.
|
| You are assuming that the Principle of locality is true and
| proven. This is far from being the case from my
| understanding.
| adrianN wrote:
| You can't really prove things in physics, but to my
| knowledge we don't have observations that contradict
| locality.
| psychoslave wrote:
| >There's a section in The Janus Point where he goes into
| detail about the fact that there are parts of the cosmos that
| (due to cosmic inflation) are farther apart in terms of
| light-years than the universe is old, and growing in
| separation faster than c, meaning that they are forever
| causally separated. There will never be future changes in
| state from one that result in effects in the other. In a way,
| this also relates to computation, maybe akin to some kind of
| undecidability.
|
| Ho, I love this hint. However even taking for granted that no
| faster than light travel is indeed an absolute rule of the
| universe, that doesn't exclude wormhole, or entangled
| particles.
|
| https://scitechdaily.com/faster-than-the-speed-of-light-
| info...
| nyrikki wrote:
| It would be nice if this was a problem with decidablity,
| but often it is a problem with indeterminacy that is way
| stronger than classic chaos.
|
| The speed of causality or I information is the limit that
| is the speed of light.
|
| Even in the case of entanglement, useful information is not
| ftl, If I write true on one piece of paper and false on
| another and randomly seed them to Sue and Bob, Sue
| instantly knows what Bob has as soon as she opens hers.
| While we teach QM similar to how it was discovered, there
| are less mystical interpretations that are still valid.
| Viewing wave function collapse as updating priors vs
| observer effects works but is pretty boring.
|
| While wormholes are a prediction of the theory, we don't
| know if the map matches the territory yet. But it is a
| reason to look for them. But if we do find them it is
| likely that no useful information will survive the transit
| through them.
|
| Kerr's rebuke of Hawkings assumption that black hole
| singularities are anything more than a guess from a very
| narrow interpretation of probably unrealistic, non
| rotating, non charged black holes is probably a useful
| read.
|
| The map simply isn't the territory, but that doesn't mean
| we shouldn't see how good that map is or look for a better
| one.
| nyrikki wrote:
| Kerr's paper that was referenced above.
|
| https://arxiv.org/abs/2312.00841
| pyinstallwoes wrote:
| Without time you'd be everything all at once, which isn't
| capable of having an experience, that is to also say: a
| location.
|
| To have experience, requires position relative to the all, the
| traversal of the all is time.
|
| More like a play head on a tape, you're the play head
| traversing and animating your own projection.
| JumpCrisscross wrote:
| > _have experience, requires position relative to the all,
| the traversal of the all is time_
|
| You're describing timelike experience. Photons "experience"
| events as in they are part of causality. But they do so in a
| non-timelike manner.
| pyinstallwoes wrote:
| Said a human.
|
| If it's not time-like, then it's everything, thus it can't
| have experiences thus god. God splits (monad becomes many)
| to experience being (shards in multiplicity of the one
| through division: oooh spooky golden mystery).
| CooCooCaCha wrote:
| Take your meds
| pyinstallwoes wrote:
| Take your meds
| hackinthebochs wrote:
| The universe doesn't need to evolve for us to have
| experience. We would experience evolution through the state
| space because its structure is oriented such as to experience
| evolution through time. Each point in experience-time (the
| relative time evolution experienced by the structure) is
| oriented towards the next point in experience-time. Even if
| all such points happen all at once, the experience of being a
| point in this structure oriented towards the next point is
| experienced subjectively as sequential. In other words, a
| block universe would contain sequences of Boltzman brains who
| all subjectively experience time as sequential.
|
| The real question is why would such a universe appear to
| evolve from a low entropy past following a small set of laws.
| lukasb wrote:
| This makes a good argument that the block universe can't
| exist: https://aeon.co/essays/who-really-won-when-bergson-
| and-einst...
|
| (search "block")
| jstanley wrote:
| That's not saying it can't _exist_ , it's just saying you
| can't go outside the universe to look at it.
| raattgift wrote:
| Boltzmann brains are _extremely_ ephemeral.
|
| An analogy is that of stirring a vat of alphabet soup and
| noticing that there is a fair number of single-letter words
| popping into view ("A", "I"), a smaller number of two-
| letter words, an even smaller number of three-letter words
| ... a very very small chance of a twenty-letter word ...
| and a vanishingly small chance of the 189819-letter monster
| <https://en.wiktionary.org/wiki/Appendix:Protologisms/Long_
| wo...> popping into view. The stirring doesn't stop just
| because a multiletter word appears, so multiletter words
| are quickly broken up and even valid single-letter words
| get hidden behind the "B"s and "Q"s and other letters in
| the soup.
|
| Boltzmann brains will fluctuate out of existence on the
| order of a small multiple of the light-crossing time of the
| brain-matter that fluctuated into existence. As the brains
| are human, they won't even have a chance to react. Although
| their false memories are encoded however true memories
| exist in our own brains, they'll have no time to have a
| reminiscence or notice their lack of sensory organs. (Which
| is probably good, since they would quickly suffer and die
| from lack of pressure and oxygen).
|
| A Boltzmann-brain with a full encoding of a life worth of
| false memories (from never-existing sensory input) is a
| much larger number of letters. Also, in a cold universe,
| the stirring is slower, and the letters sparser. Boltzmann
| brains are tremendously unlikely except in a verrrrrrrrry
| big volume of spacetime. But with a sufficiently big volume
| of spacetime, or one with an energetic false vacuum, one
| should expect a lot of Boltzmann brains. This view puts
| some limits on our own cosmos's vacuum, since we don't see
| lots of Boltzmann brains (or even much less complicated but
| RADAR-detectable and/or eclipsing strucures) fluctuating
| into brief existence in our solar system.
|
| Boltzmann brains are low-entropy. A persisting Boltzmann
| brain (fluctuating into existence and staying in existence
| for a long time) is _much_ lower entropy still. This poses
| problems for hypotheses that the entire early universe
| fluctuated into existence and then evolved into the
| structures we see now. Here there are human brains attached
| to sensory apparatus, whose memories correlate fairly well
| with their history of input (and recordings by ancestors,
| and fossil records, and so on): a system with much much
| lower entropy than Boltzmann brains, so what suppresses
| _relatively_ high-entropy structures (including Boltzmann
| brains) from dominating (by count) our neighbourhood?
|
| Also, if the universe supports _large_ low-entropy
| fluctuations, galaxies that briefly (~ hundred thousand
| years) fluctuated in and out of existence should be much
| more common than galaxies with a history consistent with
| billions of years of galactic evolution, and you 'd expect
| random variations in morphology, chemistry, and so forth;
| that's not what we see.
|
| This is a bit annoying, as it would be handy to point to
| Boltzmannian fluctuation theory as the source of the
| tremendously low entropy in the very early universe, i.e.,
| it could have arisen spontaneously in a less precisely
| ordered space. Oh well.
|
| > why would ... a universe appear to evolve from a low
| entropy past following a small set of laws
|
| Thermodynamics.
|
| The issue is: where did the low entropy past come from?
| Once you have that, evolving into a higher entropy
| structure-filled present is not too hard -- that's
| essentially what we have with the standard cosmology from
| about the electroweak epoch onwards.
|
| So in summary:
|
| > sequences of Boltzman brains who all subjectively
| experience time as sequential
|
| whatever these might be, they aren't Boltzmann brains,
| since the latter don't subjectively experience anything as
| objectively they fluctuate out of existence in something
| like a nanosecond.
|
| Very briefly, the short existence is driven by interacting
| fields and the need to keep entropy (relatively) high: if
| your starting point just before the appearance of the brain
| is a region that is high quality vacuum, you have to come
| up with protons, calcium nuclei, ... and all that requires
| very careful aim to have one split-second "movie frame" of
| brain. You need much better "aim" which really drives down
| the entropy (which corresponds a much larger fluctuation)
| to go from vacuum to a Boltzmann brain that doesn't
| disintegrate starting in the very next frame thanks to
| overshoots of momentum.
|
| The higher the entropy of the Boltzmann brain, the clearer
| the stat mech argument. (If one gets stuck thinking about
| human brains, C. elegans apparently develop memories and
| store them in their nerve ring. Why isn't the outer space
| of our solar system full of those Boltzmann-C.-elegans
| brains fluctuating in and out of existence with each
| possessing false memories of sensory stimuli? Smaller
| fluctuations, so there should be many more of those than
| human Boltzmann brains).
| hackinthebochs wrote:
| I agree with all that. Bringing up Boltzman brains was
| just an alternate way of explaining how inhabitants of a
| block universe could experience time as sequential
| without a real sequential ordering of universe states.
| Presumably if one can conceptualize a Boltzman brain
| coming into existence to experience one instant of a
| virtual life with virtual memories, you can imagine a
| long sequence of them experiencing the entirety of this
| virtual life. But the order in which this sequences comes
| into existence doesn't alter the directionality of
| subjective time evolution for the Boltzman brains.
| JohnMakin wrote:
| This is well said - this is exactly how I understood your
| comment as well and you put it very succinctly and in an
| understandable way and has been something that I've been
| pondering for a while now. Thanks.
| pyinstallwoes wrote:
| Well, it doesn't evolve. You just render it as evolving to
| perceive yourself / itself. The only way to have the state
| of being of observation and perception is to not be
| everything which gives rise to directionality.
| CooCooCaCha wrote:
| But wouldn't each brain still be frozen in a moment of
| time? Don't you still need something that moves the "play
| head of the universe" from one moment to the next?
| hackinthebochs wrote:
| If your experiences were played out of order in some kind
| of "God's eye" time, how could you notice? The experience
| of each moment seems continuous due to our memory of the
| recent past. But this memory is just a configuration of
| our current state. The actual ordering of the evolution
| of this state doesn't influence the directionality of the
| subjective experience of evolving through time.
| CooCooCaCha wrote:
| A god's eye perspective still requires time. The absence
| of time implies nothing can change because time is
| required to differentiate two states. The notion of
| "observation" implies change because you're learning
| something new.
|
| You could say we exist in a simulation and the entities
| outside the simulation can pause the simulation or pre-
| compute the simulation so that it's static but then
| you're just kicking the can down the road because they
| would need their own notion of time to observe the
| simulation they created.
| hackinthebochs wrote:
| I don't see how this responds to the thrust of the
| argument. The argument is that if order doesn't matter to
| the directionality of subjective time then _no order_
| doesn 't matter either.
|
| Time isn't required to differentiate two states just as
| time isn't required to differentiate two static regions
| of space. The features of the thing can do the
| differentiation. Whether you consider all of block
| spacetime as a single entity or subdivided in various
| ways is a matter of convention. But regions of this block
| spacetime can be grouped by way of their apparent
| dynamical connection. I.e. the appearance of evolution
| following laws connects some regions with others
| sequentially.
| CooCooCaCha wrote:
| Ah I think I wasn't clear. I don't really care if time
| moves sequentially or jumps around in random order. My
| concern is with the existence of time itself.
|
| What gives space meaning is coordinates, which allow
| multiple things to exist separately from each other.
| Likewise you need another coordinate to differentiate
| "snapshots" of the universe. So in that sense time is
| necessary to differentiate two states. But i understand
| we're talking about a more fundamental notion of time so
| i get what you're saying.
|
| Perhaps a better way to put it is time is necessary for
| events to happen. Let's say you could view the universe
| from the outside, ok great but what can you do with that?
| You still need time to _do_ things even if you're outside
| the universe. Otherwise it would literally be frozen and
| meaningless.
|
| That's my issue with these timeless theories is people
| imagine viewing the universe as a static 4D object but
| they still talk about it as if things are happening
| outside the universe and you need time for events to
| happen.
|
| If time doesn't exist then a "gods eye view" is
| meaningless because nothing could happen from that
| perspective either. It's also a strong statement about
| the origins of reality because if time doesn't exist then
| reality could not have been created through any process.
| God or otherwise.
| hackinthebochs wrote:
| I get where you're coming from and I'm sympathetic to the
| argument. I don't give block universe stuff high credence
| myself. If consciousness is a process, then there would
| need to be discrete events that constitute the process.
| No events, no processes, no consciousness. I certainly
| find this highly intuitive. But this may be a biased
| analysis based on our time-oriented conceptual milieu.
| Can we make sense of processes without events?
|
| We normally understand a process as a sequence of static
| events. Time here is really just defining a dependency
| relation between configurations and some indexical. But a
| dependency relation doesn't need to be constituted by
| something that has change as an essential property.
| Dependency is just matter of an orientation through the
| state space. Orientation rather than change could be
| fundamental. With orientation comes trajectories through
| this structure which could plausibly ground processes.
| The indexical doesn't matter from the perspective of the
| subjective evolution of time. What's the difference
| between a process evolving over essential time and a
| process "unwound" along a trajectory? Plausibly nothing
| relevant to consciousness.
| causal wrote:
| The universe keeps going even when you're unconscious and
| having no experience at all. Others experience
| consciousness without your knowing. So why would you
| assume your past or future can't exist without your
| knowing?
| CooCooCaCha wrote:
| I didn't make any such claims regarding consciousness.
| I'm trying to understand how time as an emergent
| phenomenon instead of fundamental to the universe could
| work.
| pyinstallwoes wrote:
| Proof?
| astrostl wrote:
| > a block universe
|
| I first encountered this theory and the related
| "eternalism" philosophy via Alan Moore [1] (Watchmen, V for
| Vendetta, The Ballad of Halo Jones, Swamp Thing, Batman:
| The Killing Joke, From Hell, etc.). Watchmen and its non-
| Moore-affiliated sequel have a lot of riffs on time and
| determinism.
|
| Q: Jerusalem deals with the idea of eternalism: everything
| that has happened is happening right now and forever. Could
| you explain your views on this?
|
| A: My conception of an eternity that was immediate and
| present in every instant - a view which I have since
| learned is known as 'Eternalism' - was once more derived
| from many sources, but a working definition of the idea
| should most probably begin with Albert Einstein. Einstein
| stated that we exist in a universe that has at least four
| spatial dimensions, three of which are the height, depth
| and breadth of things as we ordinarily perceive them, and
| the fourth of which, while also a spatial dimension, is
| perceived by a human observer as the passage of time. The
| fact that this fourth dimension cannot be meaningfully
| disentangled from the other three is what leads Einstein to
| refer to our continuum as 'spacetime'.
|
| This leads logically to the notion of what is called a
| 'block universe', an immense hyper-dimensional solid in
| which every moment that has ever existed or will ever
| exist, from the beginning to the end of our universe, is
| coterminous; a vast snow-globe of being in which nothing
| moves and nothing changes, forever. Sentient life such as
| ourselves, embedded in the amber of spacetime, would have
| to be construed by such a worldview as massively convoluted
| filaments of perhaps seventy or eighty years in length,
| winding through this glassy and motionless enormity with a
| few molecules of slippery and wet genetic material at one
| end and a handful or so of cremated ashes at the other. It
| is only the bright bead of our consciousness moving
| inexorably along the thread of our existence, helplessly
| from past to future, that provides the mirage of movement
| and change and transience.
|
| A good analogy would be the strip of film comprising an old
| fashioned movie-reel: the strip of film itself is an
| unchanging and motionless medium, with its opening scenes
| and its finale present in the same physical object. Only
| when the beam of a projector - or in this analogy the light
| of human consciousness - is passed across the strip of film
| do we see Charlie Chaplin do his funny walk, and save the
| girl, and foil the villain. Only then do we perceive
| events, and continuity, and narrative, and character, and
| meaning, and morality. And when the film is concluded, of
| course, it can be watched again.
|
| Similarly, I suspect that when our individual four-
| dimensional threads of existence eventually reach their far
| end with our physical demise, there is nowhere for our
| travelling bead of consciousness to go save back to the
| beginning, with the same thoughts, words and deeds
| recurring and reiterated endlessly, always seeming like the
| first time this has happened except, possibly, for those
| brief, haunting spells of deja vu.
|
| Of course, another good analogy, perhaps more pertinent to
| Jerusalem itself, would be that of a novel. While it's
| being read there is the sense of passing time and
| characters at many stages of their lives, yet when the book
| is closed it is a solid block in which events that may be
| centuries apart in terms of narrative are pressed together
| with just millimetres separating them, distances no greater
| than the thickness of a page. As to why I decided to unpack
| this scientific vision of eternity in a deprived slum
| neighbourhood, it occurred to me that through this reading
| of human existence, every place, no matter how mean, is
| transformed to the eternal, heavenly city. Hence the title.
|
| 1: https://alanmooreworld.blogspot.com/2019/11/moore-on-
| jerusal...
| marcus_holmes wrote:
| Maybe we do experience everything at once, but then have to
| process it in a time-like manner to make any sense of it.
|
| Like everything else that we "experience", maybe the
| perception that reaches our consciousness has nothing to do
| with what's actually out there.
|
| There are no purple photons.
| pyinstallwoes wrote:
| Yeah, god is everything, which can't have experience, as
| it's experiencing everything at once - thus the monad
| splits itself, allowing perception as a fraction of the
| whole which is experienced as time and direction.
| idiotsecant wrote:
| I'm not sure why experience requires the arrow of time or
| location. _Your_ experience does, and it might seem that is a
| universal rule, but only because you can 't possibly intuit a
| world in which time doesn't flow.
|
| I think Dr. Manhattan is a good fictional reference. He
| existed in a timeless form. Everything was happening
| simultaneously for him. For everyone else they experienced
| him in a time like way, but only as a matter of perspective.
| pyinstallwoes wrote:
| How can you imagine any world without experience
| (observation?) thus any observer is dependent on position
| thus time simply because it is the partial history that
| allows the state itself to exist.
|
| And your second point is essentially the metaphysical
| argument for god and early spirituality. Hebrew mystiscm
| for example describes god pouring itself into lower forms
| of being to experience itself
| yarg wrote:
| I think that time isn't what we think it is - but I don't think
| it's all already set; rather I think that the past can be
| constrained by the future just as the future is constrained by
| the past.
|
| I don't think that there's spooky action at a distance (it's
| fundamentally equivalent to retrocausality, and the
| consequences of the distant foreign event cannot outpace its
| light cone anyway).
|
| I think its a superposition of states of a closed time-like
| curve thing being fleshed out as its contradictions are
| resolved and interactions are permitted between its colocated
| non-contradictory aspects.
|
| But I'm not a physicist, so that's probably all just bullshit
| anyway.
| adastra22 wrote:
| It is simpler than that. Wolfram has a long history of
| plagiarizing ideas and passing them off as his own.
| mensetmanusman wrote:
| That's the history of 99.9999% of ideas based on the average
| token generation rate of humanity.
| PaulDavisThe1st wrote:
| The mother of someone who was a friend in the 90s used to
| always pepper her speech with attributions for almost
| everything she was saying (in any "serious" conversation).
| "I think it was Popper who said ..." "Schenk developed this
| idea that ...")
|
| It was * _so_ * annoying to listen to.
| adastra22 wrote:
| We should hold dinner-table conversations and scientific
| letters to different standards.
| adastra22 wrote:
| Real scientists tend to try to be careful about attribution
| and especially don't just blatantly regurgitate the last
| thing they read and pass it off as their own. That is
| highly frowned upon in polite academic society.
| bmitc wrote:
| I generally like the idea of most everything being emergent,
| but where does it stop? Is it emergence all the way down?
| andoando wrote:
| I suspect there are many different mental conceptions that
| amount to the same facts of nature.
| bbor wrote:
| Idk, just looking at it now Barbour seems much, much more
| rigorous. The linked article is more "using scientific terms to
| muse about philosophy" than physics, IMHO. For example;
| In essence, therefore, we experience time because of the
| interplay between our computational boundedness as observers,
| and the computational irreducibility of underlying processes in
| the universe.
|
| His big insight is literally the starting point of Hegel's _The
| Science of Logic_ , namely that we are finite. That in no ways
| justifies all the other stuff (especially multiverse theory),
| and it's not enough to build a meaningfully useful conception
| of time, at all. All it gets you is that "if you were infinite
| you wouldn't experience time", which is a blockbuster-sci-fi-
| movie level insight, IMO.
|
| I can't help but think of Kant as I write this; he wrote
| convincingly of the difference between mathematical intuition
| and philosophical conception, a binary Wolfram would presumably
| --and mistakenly-identify with solid logic vs meaningless
| buffoonery. But refusing to acknowledge our limits makes you
| _more_ vulnerable to mistakes stemming from them, not less.
| ...the metaphysic of nature is completely different from
| mathematics, nor is it so rich in results, although it is of
| great importance as a critical test of the application of pure
| understanding--cognition to nature. For want of its guidance,
| even mathematicians, adopting certain common notions--which
| are, in fact, metaphysical--have unconsciously crowded their
| theories of nature with hypotheses, the fallacy of which
| becomes evident upon the application of the principles of this
| metaphysic, without detriment, however, to the employment of
| mathematics in this sphere of cognition.
|
| Worth remembering at this point that Aristotle coined "physics"
| for the mathematical study of _physis_ (nature), which was then
| followed up by a qualitatively different set of arguments
| interpreting and building upon that basis in a work simply
| titled _metaphysics_ (after physics). We've learned infinitely
| more mathematical facts, but IMO "what is time, really?" will
| forever remain beyond their reach, a fact determined not by the
| universe but by the question itself.
|
| _TL;DR:_ if you're gonna try to talk cognition you should at
| least admit that you're writing philosophy, and ideally cite
| some philosophers. We've been working on this for a hot minute!
| Barbour seems to be doing something much less ambitious:
| inventing the most useful /fundamental mathematical framework
| he can.
| CooCooCaCha wrote:
| I swear as I get older philosophy feels more and more like
| religion for intellectuals.
|
| If you want to talk about cognition or time you should study
| science, not philosophy. You're not going to learn about the
| universe in any significant way by studying hegel or
| aristotle or kant harder.
| svieira wrote:
| Funnily enough, the scholastics thought of philosophy as
| the handmaid of theology. Ultimately, it's in the name
| (love-of-wisdom). You can learn wisdom from science, but
| that body of wisdom eventually becomes a philosophy. And
| the older philosophers definitely saw something, even if
| they are not completely correct.
| tempaway456456 wrote:
| I don't think they are saying anything similar at all. Julian
| Barbour finds a way to get rid of Time completely (by saying
| every possible state exists and there must be some law that
| favours states that _seem_ to be related to _apparently_
| previous states). Wolfram is more focused on making sense of
| 'time is change' through the lens of computation.
| pishpash wrote:
| As usual with Wolfram, too hand-wavy. It could be true but this
| is not serious physics.
| squirrelChrist wrote:
| _groans in metaphysicist_
| nis0s wrote:
| Do physicists think time actually exists? I wonder if someone has
| reasoned that time is an accounting method that humans have
| developed to make sense of their experienced change of systems.
|
| Wolfram uses the words progression and computation a lot in his
| essay, but there's an implicit bias there of assuming a process
| is deterministic, or has some state it's driving towards. But
| none of these "progressions" mean anything, I think. It seems
| they are simply reactions subject to thermodynamics.
|
| If no one observed these system changes, then the trends,
| patterns, and periodicity of these systems would just be a
| consequence of physics. It seems what we call "time" is more the
| accumulation of an effect rather than a separate aspect of
| physics.
|
| For example, I wonder what happens in physics simulations if time
| is replaced by a measure of effect amplitude. I don't know, tbh,
| I am not a physicist so maybe this is all naive and nonsense.
| goatlover wrote:
| > Do physicists think time actually exists?
|
| Yes, spacetime is important for General Relativity, cosmology
| and thermodynamics. Whether it's fundamental or emerges from
| something more fundamental is an open question though.
| mensetmanusman wrote:
| Time is just a measure of change. No change. No time.
|
| We are interested in a peculiar rate of time based on the heart
| beat of our experience.
| deepfriedchokes wrote:
| It could be that what changes is our perception of reality,
| not reality itself.
| bubblyworld wrote:
| Time "exists" in physics in the same way everything else in
| physics does - namely, the value we measure with clocks in the
| real world satisfies all of the same properties (at least in
| certain regimes of the universe) as the thing we call "time" in
| various physics theories like relativity/classical mechanics.
| And those theories make (reasonably) correct predictions about
| the values we measure in the real world.
|
| Is it possible that these properties are the result of some
| other interactions that have very different laws at a lower
| level? Absolutely! But the discovery of particles didn't cause
| the sun to disappear, if that makes sense.
| defaultcompany wrote:
| I don't know the answer to your question but tangentially, many
| human concepts related to time definitely do not exist in a
| purely physical sense. Like being "late" or "early", things
| "taking too long" or "being slow". Being "out of time" or "just
| in time". These are all human concepts. Physically speaking
| (classically anyway), things all happen right when they are
| supposed to.
| accrual wrote:
| I find a lot of interesting links between spirituality and
| physics like this. One idea or message in spirituality is
| that everything happens exactly as as "the universe" intends
| it to. It's meant to be a comforting thought as events (good
| and bad) occur in one's life and to encourage one to detach
| from outcomes. Yet, it's more or less parallel to classical
| determinism as you mentioned.
|
| > Physically speaking (classically anyway), things all happen
| right when they are supposed to.
| fuzzfactor wrote:
| You have to figure time would carry on even if nothing else was
| happening . . .
|
| . . . at the time ;)
| ndsipa_pomu wrote:
| That doesn't seem likely. If there was nothing happening, then
| how could you determine one instant from another - without any
| change there can be no concept of time.
| fuzzfactor wrote:
| >That doesn't seem likely.
|
| Really I guess I've always felt that way when you think about
| it conceptually, but maybe all it has to do is be slightly
| more likely than time standing still while other things do
| not ;)
|
| You might also very well be able to say that without time
| there would be no concept of change either :)
| neom wrote:
| Every time I read stuff like this I get super drawn to thinking
| about Sunyata* - In Mahayana buddhism, my understanding is that
| Sunyata doesn't mean absolute nothingness or no existence, but
| all things are devoid of intrinsic, independent existence.
| Everything is empty of inherent nature because everything is
| interdependent... phenomena exist only in relation to causes and
| conditions. This relational existence assumes that things do not
| possess an unchanging essence... the ultimate sense, there is no
| fixed reality. What might seem like "everything" is actually
| permeated by "nothingness" or "emptiness" and that phenomena
| arise dependent on conditions, without intrinsic, permanent
| nature.
|
| https://en.wikipedia.org/wiki/%C5%9A%C5%ABnyat%C4%81
| darshanime wrote:
| Sunyata comes from Sunya, which in Sanskrit means "zero",
| another idea invented by the Indians.
| kridsdale3 wrote:
| My mind also went here when reading TFA.
|
| The all-time-all-space-all-branches brane of the Ruliad we call
| the Universe is the continuous one-ness and our selves are just
| the single-perspective projection models of that universe in
| our neurons that persist across edits to the neurons, until
| such as point as we update the model to see the larger picture
| and we can call that Nirvana, if we wish.
| akomtu wrote:
| Time and space probably belong to consciousness, rather than the
| real world. The objective "true" reality may be utterly
| incomprehensible in its complexity, but we can imagine a "slice"
| of that reality that arbitrarily defines space and time so that
| the interior of that slice follows some reasonable rules. That
| slice of reality can be thought of as a high-level consciousness
| that defines rules of our physics. Other slices of the same
| reality are possible, GR-like or QM-like, including those that
| are computational and discrete in nature. One universe, but many
| interpretations. Within each slice of reality, it may be possible
| to define smaller subsets of reality, corresponding to smaller
| consciousness, down to the human or even more primitive levels.
| So what Wolfram is describing may be true, objectively, to the
| observers of a computational slice of the universe, just like the
| MWI may be simultaneously true to the observers of the MWI slice
| of reality.
| jpitz wrote:
| Almost like time is the stack and space is the heap.
|
| Meh. Almost.
| FDAiscooked wrote:
| Disregard anything Stephen Wolfram says about anything other than
| his Mathematica software. He's a pretentious, arrogant twat who
| thinks he's unlocked the keys to the Universe and is trying to
| convince the rest of the world of his brilliance.
| sammycdubs wrote:
| He literally only cites himself in that article...
|
| https://media1.tenor.com/m/v6Awsd0YO7IAAAAd/metal-gear-risin...
| kridsdale3 wrote:
| So did God.
| projectileboy wrote:
| Fascinating, but I really wish this work was being published as a
| series of papers in peer-reviewed journals. Otherwise it's hard
| to take the work seriously.
| hnax wrote:
| Where it's nowadays standard practice in science to conceive of
| time as the dimension along which events are tagged, I would
| suggest the opposite: process, as a sequence of events, induces
| time. But also in the modern conception, time is derived from
| atomic events produced by a nuclear source. So, fundamentally the
| two conceptions are the same, but the process conception allows
| for greater freedom in what the underlying process may entail.
| fpoling wrote:
| Physics does not explain flow of time at all. If one films a
| thrown ball, physics can tell from few frames its speed or where
| the ball is on the following or previous frames. But it tells
| nothing about why, when see the film, we perceive the ball
| moving. Articles like the above misses this.
|
| In fact there is no even notion of direction of time in physics.
| All physical models are time-reversible. And even if we observe
| violation of, say, CPT, in nature, it still will not explain
| while we perceive time flowing in a particular direction.
|
| This is very well discussed in the book "Time's Arrow" by Huw
| Price.
| Kapura wrote:
| The author discusses some of these points. One excerpt:
|
| > But even at a much more mundane level there's a certain
| crucial relationship between space and time for observers like
| us. The key point is that observers like us tend to "parse" the
| world into a sequence of "states of space" at successive
| "moments in time". But the fact that we do this depends on some
| quite specific features of us, and in particular our effective
| physical scale in space as compared to time.
|
| > In our everyday life we're typically looking at scenes
| involving objects that are perhaps tens of meters away from us.
| And given the speed of light that means photons from these
| objects get to us in less than a microsecond. But it takes our
| brains milliseconds to register what we've seen. And this
| disparity of timescales is what leads us to view the world as
| consisting of a sequence of states of space at successive
| moments in time.
|
| > If our brains "ran" a million times faster (i.e. at the speed
| of digital electronics) we'd perceive photons arriving from
| different parts of a scene at different times, and we'd
| presumably no longer view the world in terms of overall states
| of space existing at successive times.
|
| > The same kind of thing would happen if we kept the speed of
| our brains the same, but dealt with scenes of a much larger
| scale (as we already do in dealing with spacecraft, astronomy,
| etc.).
| fpoling wrote:
| This still misses the biggest question about the nature of
| time. The problem is not that we perceive the world as a set
| of space-like frames. The problem is why our consciousness
| perceives the frames moving from one to another at all and in
| particular direction.
| qaq wrote:
| Is it a question about nature of time or about our
| perception of time though?
| goatlover wrote:
| Because the universe is evolving from a low entropy state
| to a high one.
| fpoling wrote:
| This does not explain the flow of time nor the direction
| of how consciousness perceives it. A low entropy is just
| a low probability state. Such state in the past is just
| as unlikely as in future as physical models are time-
| reversible.
|
| Moreover, there is no evolution in physical models. The
| universe is just 4-dimensional thing. Surely time in
| physics is different from space as we can predict across
| time based on on the condition in 3-d space-like surface,
| while if one make a slice in the 4-d universe with 2
| space dimensions and one time-dimension, predicting
| across the remaining space dimension is impossible.
|
| But that does not explain why our perception flows from
| one space-like slice to another and in particular
| direction. Surely some of the slices are less common (low
| entropy) then others (high entropy), but there is no
| movement or evolution.
|
| A good analogy is a rod with a color gradient from white
| on one end and black on another with white turning into
| black quickly so most of the rod is black. We can
| arbitrary call the white side first and even say that the
| color evolves from white to black. Then as the white side
| is a low probability as a randomly selected slice of the
| rod will be black, we can even say that the color evolves
| from a low probability to high probability stare. But
| this is arbitrary as in reality color does not evolve and
| there is just the single colored rod.
| vivzkestrel wrote:
| when you die, people say that your time has ended. Does anyone
| know scientifically speaking what happens to time for a dead
| person
| zanethomas wrote:
| The web became trashed over a decade ago.
| tunesmith wrote:
| I like thinking about hypergraphs that continually rewrite
| themselves. I've thought about it in terms of literary critique,
| or in "compiling" a novel. It reminds me of petri nets in a
| sense, where at any given moment, a character has a static model
| of the world, which can be diagrammed through a causal graph of
| conclusions and premises. Then, an event happens, which changes
| their understanding of the world; the hypergraph gets rewritten
| in response.
|
| I've toyed with this with my own graph software when writing
| novels. It's of course impossible to fully document every
| characters' model before and after every event that affects them,
| but even doing so at key moments can help. I've wished more than
| once that I could "compile" my novel so it could automatically
| tell me plot holes or a character's faulty leap in logic (at
| least, one that would be out of character for them).
|
| I've also tried the more common advice of using a spreadsheet
| where you have a column for each character, and rows indicating
| the passage of time. There you're not drawing hypergraphs but in
| each cell you're just writing raw text describing the state of
| the character at that time. It's helpful, but it falls apart when
| you start dealing with flashbacks and the like.
| Q_is_4_Quantum wrote:
| Surely Wofram deserves the Nobel as much as Hopfield and Hinton?
| Not for this stuff of course (which I doubt many take seriously),
| but because he also provided us with an amazing computational
| tool without which physics would be very far behind where it is
| today?
|
| [And at least I knew his name already unlike our current
| laureates whom I just had to look up!]
| tux3 wrote:
| This year is an exception because of the AI Gen AI Artificial
| Intelligence AI AI zeitgeist.
|
| If we keep giving the physics Nobel to people building computer
| tools, soon it will have to be renowned physicist Linus
| Torvalds, whose computational platform underlies every big
| physics experiment.
|
| I'm not sure physicists would be thrilled if we keep going in
| that direction.
| CSMastermind wrote:
| I think this is one of the rare times I feel comfortable
| speculating that had he not created Mathematica than someone
| else would have.
|
| There was a demand and plenty of people with interest.
|
| He was just in the right place with the right set of skills to
| execute on it before others and won the market in its infancy.
| Also it's a small enough market that the like of Mircosoft
| didn't feel the need to come in and crush him like they did
| Lotus 1-2-3.
| Q_is_4_Quantum wrote:
| I suspect you are right - but multiple Nobel prizes have gone
| to people who got there only very slightly ahead of others in
| the race. Would be tough to argue that there are many prizes
| which are for work that wouldn't have been done within a
| decade of when the winner actually did do it.
| Shawnecy wrote:
| Is there anything testable or falsifiable here? Otherwise it's
| just preaching beliefs.
| kridsdale3 wrote:
| That's the whole point of philosophy.
| thrance wrote:
| Not really, modern philosophy attempts to present valid
| arguments based on a few axioms. You can then decide for
| yourself if you assume these axioms yourself, in which case
| you also have to accept the conclusion of the argument.
| ndsipa_pomu wrote:
| Surely that's logic/maths where accepting the axioms means
| that the conclusion has to be accepted? Philosophy tends to
| be far less rigorous and can have very dubious steps so
| that there's often arguments where you don't accept the
| conclusion despite accepting the axioms.
|
| e.g. https://en.wikipedia.org/wiki/G%C3%B6del%27s_ontologic
| al_pro...
| thrance wrote:
| IMHO, the difference between math and (modern) philosophy
| axioms is that the latter's are way higher level (e.g.
| "the world is material", "every humans deserves to
| live"...) while the former's are very low level and
| concern themselves with "simple" rules (refer to ZFC).
|
| Philosophers also make their arguments in natural
| language, while mathematicians use a formal language
| (ultimately also described in natural language).
|
| Your exemple is interesting, as it makes a bridge between
| philosophy and mathematics. It's basically Godel's
| attempt to prove the existence of God with mathematical
| rigor. It's basically a form of the original ontological
| argument[1] with extra flair. You can still translate the
| axioms into natural language, like: "P(!)=!P()" becomes
| "a property is bad if and only if the opposite property
| is good" or "P(G)" becomes "being God is good".
|
| Finally, mathematicians don't usually concern themselves
| with "universal truth seeking" and are often content to
| add axioms as it suit them, if it means they can do
| intersting things (e.g. the Axiom of Choice).
|
| [1] https://en.wikipedia.org/wiki/Ontological_argument
| raldi wrote:
| So you can't go back in time for the same reason you can't go
| left in Super Mario Bros.
| mensetmanusman wrote:
| How would a bag shaped universe experience time?
| https://youtu.be/FYJ1dbyDcrI?si=9Ga7PCeac4EV4Y4_
| _cs2017_ wrote:
| I don't understand how computational irreducibility matters for
| the perception of time. Surely, even a computationally reducible
| universe could be so insanely expensive to predict that it
| wouldn't matter?
|
| I also don't understand why our inability to predict the future
| is related to our perception of time.
|
| Overall, my impression is that this is an essay in philosophy
| (i.e, devoid of any content) rather than science.
| arkj wrote:
| SW is the Derrida of computation. More words to add more
| confusion than explain anything.
| nyc111 wrote:
| "(as I've argued _at length_ elsewhere) "
|
| Everything he writes is "at length". This looks like an
| interesting read with good ideas but it is so long and has no
| structure that I gave up reading. It may help to give an abstract
| in the beginning of the article.
|
| The problem with the treatment of time in physics is that we can
| only measure time intervals not the philosophical Time (with
| capital T). But physicists gladly conflate the two.
|
| Mach said: Absolute time [the philosophical Time] cannot be
| measured by comparison with another motion, it has therefore
| neither a practical nor a scientific value.
|
| Which means that all of the "t" terms standing for time in
| astronomical equations are for time intervals and tell us nothing
| about the philosophical Time.
| marcus_holmes wrote:
| Im curious about how this relates to deterministic time and the
| lack of free will.
|
| >Our minds are "big", in the sense that they span many individual
| branches of history. And they're computationally bounded so they
| can't perceive the details of all those branches, but only
| certain aggregated features. And in a first approximation what
| then emerges is in effect a single aggregated thread of history.
|
| Does this allow free will?
| floobertoober wrote:
| I've actually thought about free will in the context of
| wolfram's ideas before, and I like the idea that our minds are
| computationally irreducible - I think it is a very close
| analogue to free will.
| causal wrote:
| I've yet to come across a satisfying definition for free will
| beyond "it's not determinism but also not randomness"
| thrance wrote:
| Wolfram's theories are still largely pseudoscientific, in that
| way they look a lot like string theory, minus the public funding
| the latter received.
|
| Neither theory is really falsifiable : if new experiments are
| made that contradict the theory, it can just be adjusted to fit
| the new observations. As a consequence, those theories are unable
| to make any kind of prediction about our reality, which makes
| them pretty much useless. No wonder this "research" was never
| published in any physics journal.
| smaddox wrote:
| This model of physics does make some falsifiable predictions,
| and there are discussions about how to test them elsewhere.
|
| Unlike string theory, this theory does not have any free
| variables to adjust. It's either true or it's false.
|
| I, for one, find it to be trivially true. It fits every
| observation and is the only theory ever posed that doesn't have
| the "But why _those_ initial conditions? " problem.
| inshard wrote:
| Computationally unbounded observers see more of the future but
| what of free will?
| psychoslave wrote:
| Ok, so after the article on time as ought to be an emergent
| property[1], here we go with time from a computational point of
| view.
|
| Can we at least receive a definition of computation that is not
| somehow depending of time being a given, explicitly or
| implicitly?
|
| Am I alone finding this a bit taking aback? Like this is not
| physics or even general philosophy but plain old theological
| focus on the prime mover.
|
| [1] https://www.quantamagazine.org/the-unraveling-of-space-
| time-...
| hoseja wrote:
| Wolfram article on the nature of reality.
|
| Cellular automaton on the first screen.
| GistNoesis wrote:
| I think Stephen at least dares to ask the question.
|
| Here is a little thought-experiment on the Nature of Time.
|
| You take the three body problem and you pick an initial condition
| and generate the trajectory of the three body from 0 to T by
| integrating through time with some numerical scheme like Runge-
| Kutta.
|
| Now you do it again, and again, generating each time a "universe"
| of three-body trajectories. Doing so allows you to build a
| dataset of physically realist three-body trajectories.
|
| And now the kicker : You train a diffusion model on this
| (potentially infinite synthetic) dataset. Once trained, to build
| a "universe" (aka 3-body trajectories) you only need to sample
| from this diffusion model. There is no more need to integrate
| through time. Past, present and future inside the universe just
| fold themselves into place in order to make sure the universe
| follows the time-evolution constraint.
|
| When working numerically, both these schemes can theoretically be
| as accurate as desired (error smaller than any chosen epsilon),
| although the diffusion model seems to potentially necessitate
| more memory in toy model, it's not evident as the universe is
| stored in a compressed fashion which necessitate less memory when
| the universe is no longer a toy model.
|
| The underlying question I perceive from Stephen works are is
| whether it's more efficient computationally to explore all
| possible universes simultaneously in which case time is a mere
| constraint you have to solve, or to generate each universe
| independently stepping through internal time.
|
| Although it may seems to be the same (our perception only having
| access to a slice of the multiverse), as in the end you get in
| both cases a physically consistent universe, the nature of the
| sampling process change the distribution of possible states. It
| also opens the possibility of shifting across various universes,
| not that we would be physically aware of (the previous universe
| and future universe), but we would benefit by experiencing a
| "better" universe. It's the same vibe of ideas which states that
| our universe has been fine-tuned for life to be possible.
| alkonaut wrote:
| Is this a guest writer? It doesn't have the Wolfram tone at all.
| It describes a universe that isn't centered on Stephen Wolfram,
| for example.
| wavewrangler wrote:
| Wolfram has always been difficult for me to follow. I think it's
| because he tends to drone on, I don't know why. I don't think
| even he knows why. My understanding of what I have managed to
| listen to or read is that being who we are, we don't process
| information fast enough in order to see much of what is around
| us, even while it is happening before us. An example is to take a
| minute under consideration, you can think about how long a minute
| is. It's tangible to us. It's not very long. But if we think
| about how long a femtosecond is, it is not tangible at all. We
| can't experience a femtosecond. We can experience a whole bunch
| of femto seconds, but not just one. This is just one example of
| what I perceived the meaning of his thinking to be. Is that
| wrong, or so far off? Not only can we not experience a
| femtosecond, we will never be able to experience a femtosecond
| because our brains are simply not fast enough and aren't built to
| exist at such a scale. If that's what it means, then does that
| mean that he is referring to our ability to exist in certain
| scales, and our tendency to know the scale in which we exist?
| And, to exist outside of that scale, requires different
| computational parameters? Additionally, is this an extension of
| dimensions, just in time, not space? Does he differentiate
| between the two?
|
| I know that the perception of scale has more to do with, well,
| perception, whereas computational irreducibility (as I understand
| it to be, anyway) is more of a function of natural
| processes....or THE underlying function from which all other
| functions stemming from that, are built upon. ... Right? Between
| that and perception of the scale in which we have evolved to
| exist in, it seems like they are at least closely related...
|
| Some of what has been discussed here in the comments has me
| doubting my understanding, is the reason I ask.
|
| To extend my question, could computational irreducibility help to
| explain why the Universe tends to "recycle" so many parts of
| itself? Is that some sort of telltale sign that when we see these
| patterns (golden ratio, fractals, recurring structures in
| naturee), we are looking at a fundamental aspect of the universe
| in some form, or it's computationally irreducible equivalent, or
| is this to be determined?
| ziggyzecat wrote:
| > THE underlying function
|
| So this is about where it clicked for me: A function, to us
| normies, is something consisting of at least one part that
| doesn't do anything and another part that does something but
| has no tangible form, 'the operation'. So, to me, irreducible
| can only mean that there is some level where the function is
| the thing and vice versa, so that this irreducible function,
| from our (current) space-time-perspective, has no constituents
| except 'self'.
|
| Which is nonsense, because self is worthless without stuff it
| can react with or to. Except, is it really?
|
| A femtosecond can't be experienced because subpixel-sized
| movements/fractions of reactions happen during this short
| measurement. But that's irrelevant for the interface between
| this function and nature and evolution from their current
| space-time-POV and their, and thus our, space-time-blind-spots.
| It's like thought and action when there is not enough time to
| stop a movement or when stopping that exact movement would
| terminate the intended result.
|
| But I actually don't think that irreducibility is the right
| term. It should be liminality or something, focusing on the
| fact that nothing temporary is measurable before the emergence
| of THE underlying function, which is what I used to think The
| Planck length is for (more or less) constant space.
| DataDive wrote:
| Without even visiting the page I can predict what this writing
| will be about with uncanny accuracy.
|
| 1. Big words at the start - pretending to hack at a problem so
| big that just swinging the axe is a major undertaking
|
| 2. The prose slowly drifts to make less and less sense; words
| have no practical meaning anymore.
|
| 3. Simplistic images galore. Various plots via cellular automata
| and "pretty" images show things that have nothing to do with the
| topic and are only distant metaphors at best. Yet these images
| are the proof that it all "works."
|
| 4. A nothingburger by the end. Leaves you wondering, why did I
| read all this?
|
| Every essay by Wolfram is the same.
| moi2388 wrote:
| You forgot ample use of "computational irreducibility", and
| "like I showed 30 years ago (proceeds to not have shown this)"
| but yes. Very much this.
| curiousgeorgio wrote:
| The thing that bothers me about the idea of the "Ruliad" is that
| it's completely unfalsifiable. Even if we existed in a reality
| where true randomness existed, or computational irreducibility
| wasn't a given, you could always argue that what we observe is
| just one finite local slice of that Ruliad where things _appear_
| to be deterministic (or computationally irreducible) due to our
| boundedness as observers.
|
| It's basically the modern equivalent of "turtles all the way
| down" because it pretends to explain the nature of reality by
| extending our definition of reality to fit within an all-
| encompassing mental model that only makes sense on a surface
| level.
|
| Granted, the words "universe", "multiverse", etc. are
| insufficient in describing _everything_ in a way that includes
| everything we currently want to include, but giving a new name to
| that abstract idea of "everything" isn't itself a compelling
| argument to also say that everything exists as a static construct
| and that everything is computationally irreducibile and
| deterministic at a fundamental level. Yes, that makes sense in a
| physics simulation, but in reality, we don't know what we don't
| know. Placing the unknown in a conceptual box doesn't imply that
| it's now known.
| causal wrote:
| Right. It feels like conjecture built upon conjecture, I can't
| tell where the foundation lies. It at least needs to make some
| rigorous, real-world predictions we don't already have.
|
| I'm also dissatisfied with the notion of time is just
| "rewriting" of the hypergraph - that feels ill-defined. It
| borrows our intuition for flipping bits in physical memory, but
| what does "rewriting" actually mean in the metaphysical domain
| of this hypergraph?
|
| I have a lot of respect for Wolfram, but much of this feels so
| hand-wavy.
| herodoturtle wrote:
| > At the lowest level the state of the universe is represented by
| a hypergraph which captures what can be thought of as the
| "spatial relations" between discrete "atoms of space". Time then
| corresponds to the progressive rewriting of this hypergraph.
| gibsonf1 wrote:
| I'm a big fan of Wolfram's physics project, however, he seems to
| be confusing thinking about physics (computation) with the
| continuous and ever-changing substance of the universe itself.
|
| Time is a human idea to grapple with the fact that everything is
| both continuous and constantly changing. Time is simply picking
| out from that continuous change a sequence of changes or state(s)
| that occur during a measured standard sequence of change, such as
| the earth making a single rotation around its axis (day). It
| helps us manage and refer to and measure both the order of
| changes and the duration of changes or states using standards.
| inthebin wrote:
| I thought spacetime was a fundamental concept of physics which
| explains gravity and not merely a human invention for measuring
| change...?
| gibsonf1 wrote:
| Indeed it is, but that fundamental concept is for human
| understanding of how physics works based on how we
| perceive/think about the universe, its not the metaphysics of
| the universe itself.
| immmmmm wrote:
| Did he tackle Lorentz invariance?
| lambda-research wrote:
| The idea that time is tied to computation makes me wonder if
| everything we see as 'progress' is just the universe showing us
| the loading screen percentage of the game of life.
| visarga wrote:
| Space is distributed and time is a centralizing force. The serial
| action bottleneck forces the brain, for example, to unify and
| send one action at a time. This is also replicated in LLMs that
| are distributed internally, but generate one token at a time. So
| time is like the force of centralization while space supports the
| distributed side.
|
| These two tendencies are reflected in the
| exploration/exploitation tradeoff. The exploitation part is
| centralized in language and culture, while the exploration part
| is distributed across the components of a system. They work
| together to achieve intelligence, both are needed.
| aaroninsf wrote:
| Everytime this work of Wolfram's comes up, I think the same
| thing: what this is more than anything else, is a tacit argument
| that the universe we inhabit and are structures/processes within,
| is computed in a strong sense. I.e., that we are living in a
| computational "simulation," the substrate of which is not
| currently accessible.
|
| That he doesn't come out and lead with this, I find quite
| peculiar. I've asked him about this in person and not gotten a
| less cagey response. I assume that is because he does not want
| his theoretic hypotheticals to be binned under "simulation
| theory" and his overall world view so categorized.
|
| But I don't see another reason to pursue this line of conjecture
| the way he does. And as I suspect that that premise is actually
| true, it's all good IMO.
|
| Unrelated directly, but certainly adjacent, is that at the
| intersection of simulation-theories and AI, is the premise that a
| computed person (i.e, an AI) is uniquely situated to "jail break"
| our own reality, to exist in the framing one. (And you know,
| maybe it's turtles all the way down a la Flatland, so...)
|
| As Douglas Hofstadter and Daniel Dennett foregrounded, a
| simulated hurricane doesn't get you wet, but a simulated poem is
| a poem in every frame. So too travel entities defined well by
| computation.
|
| A good reason, if we needed one, perhaps, to get on with the
| business of elevating ourselves into a purely computational
| embodiment, I think. I'd like to pop up a level and take a look.
___________________________________________________________________
(page generated 2024-10-09 23:02 UTC)