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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

#31

Post by cryptonector »

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?

> How does this work with matter falling into 'our' black hole and hawkins-radiation leaving our black hole?

We would see that at the edge (if we could see it) there's new mass and energy, but that would be obscured by what appears as the CMB for us.

> Heck, Hawkins radiation means black holes can evaporate. Does that correspond to a universa collapsing?

No, it corresponds to stuff disappearing from our universe, until someday nothing is left.

> Would matter falling into our black hole come shooting out of the white-hole we see?

We'd see it as being part of the Big Bang, behind the CMB, so we wouldn't see it.

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

Er, not in any way that we could observe, so it's not a question we could answer. But we could receive information from the outside, except that the CMB would hide it from our prying eyes.

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

#32

Post by itronitron »

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.

what exactly is a flat region in high gravity?

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

#33

Post by tremon »

Mertax wrote: post #26
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…

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

I don't understand this logic. To me, that's equivalent to saying "there's no absolute direction for which way a wheel spins, it's relative to the speed of the observer". Which makes no sense to me, because my definition of spin is measured against the axis of rotation of the object itself.

I don't see how time-intermittent frame captures from our own position affect that interpretation. Or are we using an astonomy-specific definition of spin here?

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

#34

Post by nextaccountic »

Aerroon wrote: post #19
nextaccountic wrote: post #17

Earlier quoted context omitted.

Only the infinitesimally small singularity that is in the future of all objects inside the event horizon is supposed to be very dense. The space inside the event horizon is supposed to be normal-ish

If such a singularity exists at all. The thing we "observe" about black holes is the event horizon. It could be that space inside a black hole is just regular space.

Yep! Generally speaking singularities only appear because the math is deficient in some way. Other areas of physics successfully got rid of unphysical singularities by employing better math, it's just that we don't know how to fix this aspect of general relativity (maybe quantum gravity will?)

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

#35

Post by rocqua »

cryptonector wrote: post #31
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?

> How does this work with matter falling into 'our' black hole and hawkins-radiation leaving our black hole? We would see that at the edge (if we could see it) there's new mass and energy, but that would be obscured by what appears as the CMB for us. > Heck, Hawkins radiation means black holes can evaporate. Does that correspond to a universa collapsing? No, it corresponds to stuff disappearing from our universe, unt…

Hawking radiation can't just be stuff dissapearing, because the actual singularity can dissolve. Besides, where would the stuff even leave from? I could imagine the mass flux through our event horizon being related to the energy driving space expansion (or contraction). That only makes sense if time on the inside is related to time on the outside though.

The idea that any mass that will ever fall into our black hole all simultaneously appeared at the big bang doesn't feel correct. That suggests a very specific relationship between time on the inside and outside. There are at least two moments that are distuinishable on both sides. The singularity appearing, and the singularity dissapearing. Compressing all time on the outside into the big bang means weird things for the timing of when the singularity dissapears.

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

#36

Post by bilekas »

> "The discovery by the JWST that galaxies rotate in a preferred direction would support the theory of black holes creating new universes, and I would be extremely excited if these findings are confirmed.

Its an interesting theory but to be honest, given the conditions of the event horizon, I don’t see HOW it could be proven.. That said I do feel this will turn out to be a nuance of the measurement itself but maybe that’s just my mind not comprehending the scales of what’s being measured here.

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

#37

Post by rocqua »

Aerroon wrote: post #18
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?

Perhaps dark energy is hawking radiation. We just see what it's like from the inside. Something to consider is a possible time scale difference. Eg time could be dilated for us for being around so much density.

It would need to be the other way around, dark energy being matter falling into our black hole. Hawking radiation should 'suck' energy out of our universe. I can't think of a satisfying source of this energy. The best I can imagine is either space contracting (but that is gravity) or entropy increasing (but that doesn't leak energy, just free energy).

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

#38

Post by jacksnipe »

tremon wrote: post #33
Mertax wrote: post #26

Earlier quoted context omitted.

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

I don't understand this logic. To me, that's equivalent to saying "there's no absolute direction for which way a wheel spins, it's relative to the speed of the observer". Which makes no sense to me, because my definition of spin is measured against the axis of rotation of the object itself. I don't see how time-intermittent frame captures from our own position affect that interpretation. Or are we using an astonomy-s…

But what if you, the observer, are also rotating? What if you’re rotating faster than the thing you’re observing?

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

#40

Post by specialist »

sigmoid10 wrote: post #16

This newsblog takes one piece of the paper [1] and blows it up like it's the most obvious thing ever and completely hand-waves away the alternative, while the paper itself actually provides some compelling evidence for the alternative explanation: This asymmetry is because of our own galaxy's rotation. It would be an insane coincidence to have the large scale structure of our universe be more asymmetric towards the p…

Thanks for link. Amazing work. I'm less than noob, so barely comprehend this topic, much less this paper.

ELI5: Per "5.2 Physics of Galaxy Rotation", could the Milky Way's relative movement, in addition to its spin, also effect the observed assymetry? In Figure 10, is the Milky Way also moving toward the blue and away from the red?

Thanks for humouring my question. Everything about astronomy and JWST just blows my mind. Like how Figure 10 sorta resembles yinyang. What a time to be alive.

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