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Black Hole Evolution Traced Out with Loop Quantum Gravity

physics.aps.org

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Re: Black Hole Evolution Traced Out with Loop Quantum Gravity

#3

Post by branislav »

melling wrote: post #2

If you’re interested in black holes, Shep Doeleman’s efforts might be of interest. Taking a Photograph of a Black Hole https://youtu.be/RTKIZvDQ6Jk Einstein’s Shadow: https://www.amazon.com/Einsteins-Shadow-Black-Astronomers-Un...

I also highly recommend this [1] episode of the Omega Tau podcast which touches on black holes, holography and quantum gravity.

[1] http://omegataupodcast.net/191-string-theory/

Re: Black Hole Evolution Traced Out with Loop Quantum Gravity

#4

Post by nabla9 »

If I understood the article correctly:

1. Black hole gradually evaporates (Hawking radiation) until it's Plank size.

2. Quantum transition and Plank star.

3. White hole is formed and "the collapsed star is bouncing back".

I Always thought that black hole evaporating energy as Hawking radiation contains all the energy that went into the black hole when the evaporation is complete. This theory assumes that there is energy left.

How is the total energy that went in is distributed between the Hawking radiation and the white hole that follows the evaporation?

Are all white holes equal in size and does Hawking radiation account for the black hole size difference?

Re: Black Hole Evolution Traced Out with Loop Quantum Gravity

#5

Post by enkid »

nabla9 wrote: post #4

If I understood the article correctly: 1. Black hole gradually evaporates (Hawking radiation) until it's Plank size. 2. Quantum transition and Plank star. 3. White hole is formed and "the collapsed star is bouncing back". I Always thought that black hole evaporating energy as Hawking radiation contains all the energy that went into the black hole when the evaporation is complete. This theory assumes that there is ene…

My understanding is the transition to a white hole exists instead of a singularity at the interior of the black hole, and is therefore hidden by the event horizon. When the event horizon shrinks to the Planck length, the white hole is exposed.

Re: Black Hole Evolution Traced Out with Loop Quantum Gravity

#7

Post by SiempreViernes »

Rovelli himself wrote this more popular account and didn't manage to state a clear physical reason for the bounce, so the title is overstating the result.

I take this to be an interesting technical advance for a theory whose relevance in general is still an open question.

Re: Black Hole Evolution Traced Out with Loop Quantum Gravity

#8

Post by acd »

If white holes exist that are the inverse of black holes. The universe could exist forever. Black holes would suck matter in and white wholes on the other side would create new matter on the other side.

Black wholes and white holes would then be gateways to other universes.

Multi verse https://en.wikipedia.org/wiki/Multiverse

https://news.nationalgeographic.com/news/2010/04/100409-blac...

https://en.wikipedia.org/wiki/Wormhole

Re: Black Hole Evolution Traced Out with Loop Quantum Gravity

#9

Post by nabla9 »

enkid wrote: post #5
nabla9 wrote: post #4

If I understood the article correctly: 1. Black hole gradually evaporates (Hawking radiation) until it's Plank size. 2. Quantum transition and Plank star. 3. White hole is formed and "the collapsed star is bouncing back". I Always thought that black hole evaporating energy as Hawking radiation contains all the energy that went into the black hole when the evaporation is complete. This theory assumes that there is ene…

My understanding is the transition to a white hole exists instead of a singularity at the interior of the black hole, and is therefore hidden by the event horizon. When the event horizon shrinks to the Planck length, the white hole is exposed.

Yes, but the event horizon shrinks by emitting Hawking radiation, right?

When the white hole is exposed, what it looks like? Is it just hole in the space that does not emit anything? Nothing exits (because Hawking radiation already emitted all of the energy) and nothing can enter.

What is the radius of the white hole?

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