I Can Hawking Radiation Exist If Nothing Escapes a Black Hole?

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Hawking radiation is a theoretical prediction that suggests black holes can emit radiation, leading to mass loss and eventual evaporation, but this concept is still provisional due to the lack of a complete theory of quantum gravity. The original understanding of black holes, based on classical General Relativity, stated that nothing could escape their event horizons, a notion that has evolved with the introduction of quantum effects. Current models indicate that black holes are observed not because of radiation escaping from within, but due to their gravitational effects on surrounding matter and radiation. The discussion highlights misunderstandings about black holes and the nature of Hawking radiation. Overall, the complexities of black hole physics remain an active area of research with unresolved questions.
Walrus
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Or is Hawking radiation something? Can't be both, however if you choose one theory over another, why do you do so. Those of you who are younger will not remember a World without the information paradox, but when I was younger it did not exist in any way because nothing escaped the event horizon of the black hole which could not be seen, but now we see them. Bye the way isn't it time to change the name since they are not black anymore?
 
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Walrus said:
nothing escaped the event horizon of the black hole
The Hawking radiation that comes out originates outside the event horizon.
Walrus said:
Bye the way isn't it time to change the name since they are not black anymore?
In a few trillion trillion years when they're less black than the microwave background, maybe.
 
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Walrus said:
if you choose one theory over another
You are misdescribing what physicists are actually doing.

The prediction of classical General Relativity is that a black hole cannot lose mass. (That, btw, is the prediction that changes when Hawking radiation is taken into account. So your first misdescription is of the actual prediction that changes.)

Hawking and others have developed models that take quantum effects into account at least to some extent, and those models generally predict that black holes should emit radiation, which, if nothing else ever fell into them, would cause them to lose mass and eventually evaporate away. However, these models are only provisional because we do not have a good theory of quantum gravity.

So it is not a matter of "choosing one theory over another", it is a matter of not having a theory at all that takes into account all possibly relevant effects. But in practical terms, this is not an issue at all, because, first, the estimated Hawking evaporation time for black holes of stellar mass or larger is many, many orders of magnitude greater than the age of the unvierse, and second, all real black holes do have things falling into them--CMB radiation, if nothing else--which adds mass to them that swamps any predicted mass loss due to Hawking radiation.

Walrus said:
nothing escaped the event horizon of the black hole which could not be seen, but now we see them.
This is still another misdescription. We do not "see" black holes because of anything escaping from inside their horizons. We "see" them because of their effects on nearby objects and radiation outside their horizons.
 
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The OP is based on multiple misunderstandings, which have been corrected. This thread will remain closed.
 
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