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Is our universe trapped inside a black hole? This JWS Telescope discovery

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Re: Is our universe trapped inside a black hole? This JWS Telescope discovery

#21

Post by lostmsu »

alabastervlog wrote: post #10
jagged-chisel wrote: post #3

> These [baby] universes would be unobservable to us because they are also behind an event horizon, a one-way light-trapping point of no return from which light cannot escape, meaning information can never travel from the interior of a black hole to an external observer. Also meaning that “our” blackhole (the one containing us) is unobservable from the parent universe for the same reason. So where is all this extra l…

I figure our whole universe so far has existed in the first nanosecond (or whatever) after the creation of the black hole in the parent universe, so very little energy or light has had time to enter. By one or two seconds in the parent universe’s time scale, our universe will have settled down to its extremely long state of being a cold, dark void of slowly decomposing subatomic particles. No good reason to think thi…

Time in high gravity usually flows slower than in flat regions, not faster.

Re: Is our universe trapped inside a black hole? This JWS Telescope discovery

#22

Post by dghughes »

Aerroon wrote: post #20
alabastervlog wrote: post #10

Earlier quoted context omitted.

I figure our whole universe so far has existed in the first nanosecond (or whatever) after the creation of the black hole in the parent universe, so very little energy or light has had time to enter. By one or two seconds in the parent universe’s time scale, our universe will have settled down to its extremely long state of being a cold, dark void of slowly decomposing subatomic particles. No good reason to think thi…

Scales are a very interesting thing to think about. There's a theory that the universe didn't really 'start' with the big bang, that it was always there, but at a different scale. The big bang was essentially an increase in the scale of the universe, possibly in terms of time and space.

Our universe may be a rotating detonation engine only it's our universe being made not combustion.

Re: Is our universe trapped inside a black hole? This JWS Telescope discovery

#23

Post by perihelions »

fprog wrote: post #13

An alternate hypothesis which seems equally interesting, albeit for different reasons, is at the end of the article: > Another explanation for why the JWST may have seen an overrepresentation of galaxies rotating in one direction is that the Milky Way's own rotation could have caused it. > Previously, scientists had considered the speed of our galaxy's rotation to be too slow to have a non-negligible impact on observ…

I'm utterly confused what's going on. They're measuring galaxies' rotations by looking at images of the subset that are spiral galaxies, and checking which direction the arms spiral. They describe their image processing algorithm in their paper [0]. (it's around figure 3)

How can local movement of stars within the Milky Way affect which way spiral galaxy arms are pointing?

[0] https://academic.oup.com/mnras/article/538/1/76/8019798.

Re: Is our universe trapped inside a black hole? This JWS Telescope discovery

#24

Post by cvoss »

rocqua wrote: post #8

How does this work with matter falling into 'our' black hole and hawkins-radiation leaving our black hole? Heck, Hawkins radiation means black holes can evaporate. Does that correspond to a universa collapsing? Would matter falling into our black hole come shooting out of the white-hole we see? Would time on either side of the event horizon even be related?

> Would time on either side of the event horizon even be related?

I think that's exactly the right question to ask. And ask it for space too. Perhaps the entire history of the interior universe unfolds between the black hole's formation and its final evaporation. Perhaps a heat death of the interior universe, where everything spreads out until nothing interesting is left, can fit inside this ever shrinking volume.

Re: Is our universe trapped inside a black hole? This JWS Telescope discovery

#25

Post by Georgelemental »

perihelions wrote: post #23
fprog wrote: post #13

An alternate hypothesis which seems equally interesting, albeit for different reasons, is at the end of the article: > Another explanation for why the JWST may have seen an overrepresentation of galaxies rotating in one direction is that the Milky Way's own rotation could have caused it. > Previously, scientists had considered the speed of our galaxy's rotation to be too slow to have a non-negligible impact on observ…

I'm utterly confused what's going on. They're measuring galaxies' rotations by looking at images of the subset that are spiral galaxies, and checking which direction the arms spiral. They describe their image processing algorithm in their paper [0]. (it's around figure 3) How can local movement of stars within the Milky Way affect which way spiral galaxy arms are pointing? [0] https://academic.oup.com/mnras/article/5…

Read section 5.2 of the paper

Re: Is our universe trapped inside a black hole? This JWS Telescope discovery

#26

Post by Mertax »

perihelions wrote: post #23
fprog wrote: post #13

An alternate hypothesis which seems equally interesting, albeit for different reasons, is at the end of the article: > Another explanation for why the JWST may have seen an overrepresentation of galaxies rotating in one direction is that the Milky Way's own rotation could have caused it. > Previously, scientists had considered the speed of our galaxy's rotation to be too slow to have a non-negligible impact on observ…

I'm utterly confused what's going on. They're measuring galaxies' rotations by looking at images of the subset that are spiral galaxies, and checking which direction the arms spiral. They describe their image processing algorithm in their paper [0]. (it's around figure 3) How can local movement of stars within the Milky Way affect which way spiral galaxy arms are pointing? [0] https://academic.oup.com/mnras/article/5…

There is no absolute direction for a galaxy’s spin—it’s always relative to the observer’s perspective.

So I’d suspect they’re saying time and distance would need to be factored in rather than just looking at static images relative to our position today since our own spin may have caused a particular galaxy to appear to have been spinning in a different direction at another point in space-time

Re: Is our universe trapped inside a black hole? This JWS Telescope discovery

#27

Post by api »

It'd be neat if the universe were essentially a nested Russian doll of black holes. Our universe is a black hole with black holes inside and black holes inside them and so on, and the larger universe outside ours is also an even bigger black hole. Some of the really huge black holes in our universe might be big enough to host interesting things within, but the smaller ones probably just contain "toy" universes without much happening.

I recall reading about our universe as a black hole once -- one thing posited is that everything that is happening and what we think of as space is really information processing occurring just at the surface of the event horizon. There was some possible way of explaining non-local phenomena like entanglement that way, but I forget the details.

It's fascinating to think about how the actual universe might be something quite alien from our ordinary perception. It's not that our ordinary perception is wrong. What we're perceiving is just one perspective on something much larger and weirder. In this case our perspective would be from within this information substrate. It's almost universe-as-simulation, except that the simulation does not have a builder. It's a naturally occurring phenomenon. The Matrix has no architect, or if it does it's something fully outside the event horizon of this object and thus un-observable.

Of course at this point we're well into physicists smoking pot territory.

Re: Is our universe trapped inside a black hole? This JWS Telescope discovery

#28

Post by perihelions »

Georgelemental wrote: post #25
perihelions wrote: post #23

Earlier quoted context omitted.

I'm utterly confused what's going on. They're measuring galaxies' rotations by looking at images of the subset that are spiral galaxies, and checking which direction the arms spiral. They describe their image processing algorithm in their paper [0]. (it's around figure 3) How can local movement of stars within the Milky Way affect which way spiral galaxy arms are pointing? [0] https://academic.oup.com/mnras/article/5…

Read section 5.2 of the paper

Do you or other HN commenters understand it in a satisfying way?

The author writes about the Doppler effect creating a systemic bias in brightness depending on which way the galaxies are rotating. I don't understand that argument either, but it's moot, because they state categorically that that effect would be too small to explain their results. ("This explanation is challenged by the fact that the effect of the rotational velocity have merely a mild impact on the brightness of galaxies, and therefore is not expected to lead to the dramatic difference of 50 per cent in the number of galaxies as observed through JADES.")

That's the only explanation I recognized as an explanation. Then I lost track of their argument following that. They refer to several speculative physics theories like MOND, but I don't understand them to be saying something that concretely predicts distant galaxies to appear to be rotating differently.

I'm appealing to anyone on HN who knows enough about this field to understand the meat of this argument.

Re: Is our universe trapped inside a black hole? This JWS Telescope discovery

#29

Post by jagged-chisel »

lostmsu wrote: post #21
alabastervlog wrote: post #10

Earlier quoted context omitted.

I figure our whole universe so far has existed in the first nanosecond (or whatever) after the creation of the black hole in the parent universe, so very little energy or light has had time to enter. By one or two seconds in the parent universe’s time scale, our universe will have settled down to its extremely long state of being a cold, dark void of slowly decomposing subatomic particles. No good reason to think thi…

Time in high gravity usually flows slower than in flat regions, not faster.

With our math, yes. But maybe that’s because we are the imaginary part of the equation.
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