Can Hawking Radiation Exist If Nothing Escapes a Black Hole?

In summary, the article explores the concept of Hawking radiation, a theoretical prediction by physicist Stephen Hawking that suggests black holes can emit radiation due to quantum effects near their event horizon. It discusses the paradox of how radiation can exist if nothing is supposed to escape a black hole, examining the interplay between quantum mechanics and general relativity. The piece highlights the implications for our understanding of black holes and the universe, suggesting that Hawking radiation might allow for the slow evaporation of black holes over time, challenging traditional notions of their permanence.
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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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Thread closed temporarily for Moderation...
 
  • #4
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.
 

FAQ: Can Hawking Radiation Exist If Nothing Escapes a Black Hole?

What is Hawking radiation?

Hawking radiation is a theoretical prediction by physicist Stephen Hawking that black holes can emit radiation due to quantum effects near the event horizon. This radiation results from particle-antiparticle pairs forming near the event horizon, with one particle falling into the black hole and the other escaping, leading to a gradual loss of mass and energy from the black hole.

How can Hawking radiation escape if nothing can escape a black hole?

Hawking radiation does not actually escape from within the black hole. Instead, it originates just outside the event horizon. Quantum fluctuations cause particle-antiparticle pairs to form near the event horizon. If one particle falls into the black hole while the other escapes, the escaping particle is observed as Hawking radiation.

Does Hawking radiation violate the principle that nothing can escape a black hole?

No, Hawking radiation does not violate this principle because the radiation is not coming from inside the black hole but from just outside the event horizon. The process involves quantum mechanical effects in the vacuum near the event horizon, not the escape of material from within the black hole itself.

What happens to the black hole as it emits Hawking radiation?

As a black hole emits Hawking radiation, it loses mass and energy over time. This process causes the black hole to gradually shrink. If the black hole continues to lose mass without gaining any, it could eventually evaporate completely, although this would take an extremely long time for large black holes.

Has Hawking radiation been observed experimentally?

As of now, Hawking radiation has not been observed directly. The effect is extremely weak and difficult to detect with current technology, especially for large black holes. However, researchers continue to study indirect evidence and analogous systems in laboratory settings to better understand and potentially observe this phenomenon.

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