[HN Gopher] Tiny bright objects discovered at dawn of universe b...
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Tiny bright objects discovered at dawn of universe baffle
scientists
Author : Brajeshwar
Score : 84 points
Date : 2024-06-29 15:54 UTC (7 hours ago)
(HTM) web link (phys.org)
(TXT) w3m dump (phys.org)
| davedx wrote:
| > Leja explained that if you took the Milky Way and compressed it
| to the size of the galaxies they found, the nearest star would
| almost be in our solar system. The supermassive black hole in the
| center of the Milky Way, about 26,000 light years away, would
| only be about 26 light years away from Earth and visible in the
| sky as a giant pillar of light.
|
| Pretty crazy galaxies.
| amelius wrote:
| Things would be more crazy if it was different.
| bsenftner wrote:
| How's about super massive black holes are massive enough their
| gravity well accelerates the mass being captured faster than the
| speed of light, and they plunge back in time. The Universe is
| self regenerating, by sending super massive black holes back to
| the beginning of time, where they explode into our universe. Or
| something like that. Maybe, maybe not.
| exe34 wrote:
| this would make really good sci-fi, you should write it up!
| robxorb wrote:
| [GPT has entered the chat.]
| VagabundoP wrote:
| Not only is space time probably curved back on its self but the
| arrow of time as well. Time is a flat circle!
| ramon156 wrote:
| Maybe flat earther are yet to discover an even bigger truth,
| flat time
| EdwardDiego wrote:
| Pfft everyone knows it's a cube.
| oldmariner wrote:
| Leftovers from an old Big Crunch?
| exe34 wrote:
| it'd be tricky to get them from one side to the other. you'd
| think the quark soup would vaporise them.
| oldmariner wrote:
| Perhaps it didn't compress evenly?
|
| There's no reason a previous universe had to form, expand, or
| stay distributed evenly.
| frutiger wrote:
| Unfortunately we have not observed any anisotropy so it
| seems implausible.
| downvotetruth wrote:
| https://arxiv.org/abs/0811.2732
|
| 1. Introduction
|
| Since the discovery of the _anisotropy_ of the cosmic
| microwave background (CMB) radiation by COBE...
| exe34 wrote:
| is this the same one that penrose saw the ghost of
| universes past in?
| downvotetruth wrote:
| Penrose has published many papers on ghosts of black
| holes from another universe (see
| https://www.livescience.com/63392-black-holes-from-past-
| univ... for commentary), but 0811.2723 does not have
| Penrose as an author or state a reference to him by name.
| dagss wrote:
| When CMB anisotropies are studied, one question is to see
| the the universe is isotropic or anisotropic -- these are
| two different uses of the word isotropic, on completely
| different scales.
|
| The current prevailing science is saying that the CMB
| anisotropies are telling us the universe is isotropic...
|
| The linked paper does however talk about an apparent
| deviation from this standard picture...but that is not
| what the word "anisotropy" is about in that quote.
|
| Gurzadyan is not the most representative researcher to
| cite. While doing a PhD in astrophysics I remember a
| paper coming out where Gurzadyan co-published with
| Penrose but the paper had obvious flaws due to basic lack
| of understanding of statistical simulation, and there
| were many other groups jumping on showing it wrong within
| a few days..
|
| IIRC the problem was that it was assumed that independent
| random variables in one space would still be independent
| after a linear transform (Fourier transform/spherical
| harmonic transform). I.e. failure in basic statistical
| algebra stuff underpinning the statistical simulations.
| This was not nitpicking, the whole result vanished once
| other groups redid the experiment with corrected algebra.
|
| The talk was all about how Penrose could possibly have
| been fooled into putting his name on the paper -- and why
| he would not retract it even after many pointed out the
| blatant entry level mistakes.
| mr_mitm wrote:
| The anisotropies in the CMB are ridiculously tiny.
| Microscopic. And they're extremely evenly spread.
|
| On large scales, the universe is incredibly isotropic.
| munchler wrote:
| Everything in the observable universe compressed to an
| extremely uniform degree, as reflected in the cosmic
| microwave background radiation (CMBR), our earliest "image"
| of the universe. Variations in the CMBR are on the order of
| one part per million.
| theptip wrote:
| No, we know (because of the CMB) that everything was compressed
| into a dense plasma until ~300kyr (rough estimate from memory)
| so there was no way for these structures to survive a previous
| crunch.
| Zigurd wrote:
| It was just 101 years ago that galaxies outside the Milky Way
| were discovered and that the universe we can observe grew from
| being 100k light years to 93 billion light years in diameter. The
| existence of black holes was first observed in the 1970s. It is a
| good bet other astonishing objects are yet to be discovered.
| DexesTTP wrote:
| Not quite that, we've known about galaxies outside our own
| (like the Magellanic clouds or the Andromeda galaxy) for a few
| millenia, and the main reason black holes haven't been
| discovered for a while because they're black and we needed a
| theory to know where to look. The current theory of cosmology
| has overall been pretty stable for a while.
|
| What's interesting there isn't that much the object themselves
| which are bog-standard as far as celestial objects go, but how
| red-shifted (and therefore how far away/long ago) they are,
| which is something the model doesn't quite exclude but does
| warrant some tweakings of the "initial parameters" of the
| universe to make it work this way compared to what we expect.
| actionfromafar wrote:
| But did we know they were _galaxies_ and not just some
| shining object?
| macintux wrote:
| Their nature wasn't confirmed until the 20th century.
| Wikipedia tackles the history:
| https://en.wikipedia.org/wiki/Andromeda_Galaxy
| Hemospectrum wrote:
| > we've known about galaxies outside our own (like the
| Magellanic clouds or the Andromeda galaxy) for a few millenia
|
| Well, we could _see_ them, but we weren 't able to
| distinguish a galaxy from a nebula until after investing
| multiple centuries into the development of powerful
| telescopes.
| someplaceguy wrote:
| Maybe this is what a white hole looks like...
| prettyStandard wrote:
| Galaxy Brain thought:
|
| I feel like the big bang is a white hole.
|
| Come back I have more!
|
| All world lines end in black holes. All world lines start at
| white holes.
|
| Many Worlds theory is pretty popular. I buy into it. Every
| thing that can happen does happen, but also... There's this one
| that goes every black hole spawns a new universe, with slightly
| different laws of physics, based on the parent universe. So the
| multiverse starts favouring universes that can make new ones.
|
| Does this mean the Spiderman universe is out there somewhere?
| Even hypothetically IDK. There's probably some constraint on
| consistent laws of physics.
| DEADMINCE wrote:
| That's some great sci-fi.
| seo-speedwagon wrote:
| Naive thought incoming:
|
| If these old galaxies are so dense, could that help explain why
| their black hole is disproportionately large? With so many stars
| so close together, maybe they're gravitationally interacting with
| each other far more, causing a lot more instability. So you have
| a bunch of stars knocking each other around and as a byproduct
| more of them get flung close enough to the center to get captured
| by the black hole?
| MattPalmer1086 wrote:
| Loving how we are finding mysteries the further back we look.
| Super massive black holes far larger than our models can account
| for. Galaxies with more structure and more older population
| stars.
|
| What is it telling us? Our current ideas are certainly wrong.
| Looking forward to what it leads us to.
| awinter-py wrote:
| so quick bright things come to confusion
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