All Questions
Tagged with black-holes thermodynamics
306
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56
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Is the Hawking radiation of a charged black hole thermal?
Suppose you have a Schwarzschild black hole of mass $M$ and angular parameter $a = 0$ (no rotation).
Question: is it possible to throw a charge $Q$ at a faster rate than it will be re-radiated? Will ...
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Why is the information paradox restricted to black holes?
I am reading Hawking's "Brief answers". He complained that black holes destroy information (and was trying to find a way to avoid this). What I don't understand: Isn't deleting information quite a ...
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How much mass can colliding black holes lose as gravitational waves?
Concerning the recent detection of gravitational waves produced by colliding black holes, it has been reported that a significant percentage of the combined mass was lost in the resulting production ...
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How does one correctly interpret the behavior of the heat capacity of a charged black hole?
Note: Although I have a provided an "answer" to the question, I did not resolve all the questions in this post satisfactorily. I invite anyone willing and able to provide a better answer, which I ...
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Can a neutron star become a black hole via cooling?
How much does thermal expansion affect neutron stars? Would the loss of temperature cause a neutron star to be more densely packed and thus collapse into a black hole?
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Is there a way to split a black hole?
Classically, black holes can merge, becoming a single black hole with an horizon area greater than the sum of both merged components.
Is it thermodynamically / statistically possible to split a black ...
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Do all massive bodies emit Hawking or Unruh 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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What was the entropy of the universe at the time of the Big Bang?
(I asked this question in Philosophy.SE; but I was advised to direct it here, despite it is, in my opinion, somewhat too speculative for physics.SE).
High entropy generally means high disorder; and ...
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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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Why doesn't Hawking radiation add to the mass of a black hole just as much as it subtracts from it? [duplicate]
If 'quantum foam'-generated particles are made of matter and antimatter in equal amounts, why don't the matter particles that fall into the black hole add to the black hole's mass just as much as the ...
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Do black holes violate the first law of thermodynamics?
When a black hole absorbs matter is it destroying that mass, thereby destroying energy, therefore violating the first law of thermodynamics?
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Metric of an Evaporating Black Hole
The famous Hawking calculation is done with an assumption that the background is static, i.e. the evaporation doesn't change the mass parameter in the metric. Thus, we simply describe the geometry ...
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Why do larger black holes emit less Hawking Radiation than smaller black holes?
Pedestrian question from a non-physicist:
I read on Wikipedia that larger black holes emit less net Hawking radiation than smaller black holes.
This seems counterintuitive to me. If black holes are ...
13
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Second Law of Black Hole Thermodynamics
I've been looking for a satisfying proof of this, and can't quite find it. I read the brief proof of the black hole area theorem in Wald, which is similar, but doesn't quite come down to the actual ...
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Nothing falls into an evaporating black hole?
The Vaidya Metric is the metric that can be used to describe the spacetime geometry of a varying mass black hole. This metric reads
$$d\tau^2=\bigg(1-\dfrac{2M(\nu)}{r}\bigg)d\nu^2+2d\nu dr - r^2 d\...
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