Radiation that comes from pair production quantum effects in close vicinity to an event horizon, leading to the potential for eventual evaporation of black holes. Two mirror particles are created with one falling behind the horizon, becoming casually lost to the rest of the universe, including its ...
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633 views
Black holes and positive/negative-energy particles
I was reading Brian Greene's "Hidden Reality" and came to the part about Hawking Radiation. Quantum jitters that occur near the event horizon of a black hole, which create both positive-energy ...
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6answers
763 views
Do all massive bodies emit Hawking radiation?
It is known that any accelerated observer is subject to a heat bath due to Unruh radiation. The principle of equivalence suggests that any stationary observer on the surface of a massive body should ...
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2answers
417 views
Do apparent event horizons have Hawking radiation?
As I understand it, black holes have an absolute event horizon and an apparent horizon specific an observer. In addition to black holes, an apparent horizon can come from any sustained acceleration. ...
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3answers
332 views
Hawking radiation and reversibility
It's often said that, as long as the information that fell into a black hole comes out eventually in the Hawking radiation (by whatever means), pure states remain pure rather than evolving into mixed ...
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2answers
401 views
Extremal black hole with no angular momentum and no electric charge
A black hole will have a temperature that is a function of the mass, the angular momentum and the electric charge. For a fixed mass, Angular momentum and electric charge are bounded by the extremality ...
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0answers
84 views
Information scrambling and Hawking non-thermal radiation states
Could a very small black hole where half of its entropy has been radiated, emit Hawking radiation that is macroscopically distinct from being thermal? i.e: not a black body radiator. Or would the ...
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1answer
340 views
How do we know that black holes evaporate?
This has been bugging me for some time.
As I understand it, Hawking radiation is the result of the mismatch between the vacuum state of a quantum field as seen by a free falling observer (falling ...
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3answers
802 views
From where (in space-time) does Hawking radiation originate?
According to my understanding of black hole thermodynamics, if I observe a black hole from a safe distance I should observe black body radiation emanating from it, with a temperature determined by its ...
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2answers
576 views
Analog Hawking radiation
I am confused by most discussions of analog
Hawking radiation in fluids (see, for example,
the recent experimental result of Weinfurtner et
al. Phys. Rev. Lett. 106, 021302 (2011), ...
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3answers
360 views
Why is there a flux of radiation in the Hawking effect but not in the Unruh effect? (and other questions)
This question is slightly related to this one Do all massive bodies emit Hawking radiation?, which I think was poorly posed and so didn't get very useful answers. There are several questions in this ...
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1answer
124 views
Multipolar expansion profile of Hawking radiation on Kerr black holes
I would be very curious if Kerr black holes emit Hawking radiation at the same temperature in the equatorial bulges and in their polar regions. I've been looking some reference for this for a couple ...
8
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1answer
86 views
Hawking Radiation as Tunneling
Firstly, I'm aware that Hawking radiation can be derived in the "normal" way using the Bogoliubov transformation. However, I was intrigued by the heuristic explanation in terms of tunneling. The ...
4
votes
8answers
610 views
Flat space limit of the Schwarzschild metric and Hawking temperature
The Schwarzschild metric reduces to the Minkowski metric in the limit of vanishing $M$, but the Hawking temperature which is proportional to $1/M$ diverges in the same limit. This would imply that ...
6
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4answers
452 views
de sitter cosmologic limit
It has been said that our universe is going to eventually become a de sitter universe. Expansion will accelerate until their relative speed become higher than the speed of light.
So i want to ...
4
votes
1answer
497 views
On black holes, Hawking radiation and gravitational atoms
Over the past hour or so I've been following one of my standard physics-based, wanders-through-the-internet. Specifically, I began by reviewing some details of dark energy theory but soon found myself ...
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1answer
125 views
Intensity of Hawking radiation for different observers relative to a black hole
Consider three observers in different states of motion relative to a black hole:
Observer A is far away from the black hole and stationary relative to it;
Observer B is suspended some distance ...
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2answers
262 views
Hawking radiation from point of view of a falling observer
This paper tells that Hawking claimed that the falling to a black hole observer will not detect any radiation. But only because the frequency of the Hawking radiation will be of the order $1/R_s$ so ...
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2answers
246 views
How can one reconcile the temperature of a black hole with asymptotic flatness?
A stationary observer very close to the horizon of a black hole is immersed in a thermal bath of temperature that diverges as the horizon is approached. $$T^{-1} = 4\pi \sqrt{2M(r-2M)}$$ The ...
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231 views
Why can't light escape from inside event horizon of Black Holes?
The simple answer: Its because Gravity of Black Hole there doesn't allow it. See also this and this Phys.SE posts.
Isn't it a classical answer? When we're unable to connect Gravity with Quantum ...
