All Questions
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What are regular event horizons?
I am studying uniqueness theorems of Black Holes and I often see the word "regular event horizon" instead only event horizon. Many textbooks and literature do not define this term. Please ...
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Black hole information paradox
I read that it is generally believed that information is preserved in black hole evaporation, and people's views only diverge when it comes to how information is preserved. Is this true?
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What is the difference between the cosmological and the black hole horizons in thermodynamics?
I want to know the different thermal behaviors between cosmological and black hole horizons, such as temperature, entropy and so on.
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How increase in area of the horizon implies that the horizon in spacelike using Raychaudhuri equation?
In a talk The enigma of black hole horizons, (at 24:37), it is said that
"Raychaudhuri equation implies, if the flux into H is positive, area increases and horizon is spacelike".
How ...
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2
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Is entropy dependent on mass alone?
The entropy of a non-rotating, non-charged black hole is only proportional to the surface area of its event horizon (Bekenstein, 1973).
The area of the event horizon of a spherical black hole is only ...
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Past null horizon
What are past null horizons and future null horizons? Are they the same as past event horizons and future event horizons? The literature on Black Holes often uses these terms but I don’t get it. ...
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2
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434
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Does the interior volume of a black hole grow forever?
Recently, I was reading about a article which tells about something known as "Susskind Complexity". The article states that the interior volume of a black hole grows forever.
How/why does ...
user355398
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Ergodicity and spin connections at the event horizon
Hawking famously relates the entropy $S$ to the surface area of a black hole $A$ as $S=A/4$. Should I be thinking of the entropy as the number of possible configurations of a spin connection at the ...
- 241
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Why is the temperature of a black hole inversely related to its mass?
From what I've read
The temperature of a black hole is measured by the amount of Hawking Radiation emitted.
For a photon to escape, it must travel perfectly perpendicular to the event horizon.
The ...
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3
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Why are physicists surprised that the information of a black hole is proportional to its boundary? #2
Inspired by Why are physicists surprised that the information of a black hole is proportional to its boundary?
Intuitively, one of two things must happen to information that enters a black hole: ...
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Why are physicists surprised that the information of a black hole is proportional to its boundary?
I don't understand why physicists are surprised that the information of a black hole is proportional to its boundary.
From a pure GR perspective, in my understanding, an observer outside a black hole ...
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2
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Will a black hole disappear?
Reading The brief history of time by Stephen Hawking and the chapter 7 BLACK HOLES AIN’T SO BLACK has below.
Does it mean if his theory is correct, a black hall can disappear on its own?
Because ...
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3
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Where does all the energy in black holes go?
The temperature inside of a black hole is almost absolute zero, so particles inside a black hole have almost zero motion.
So if they don't give out any heat or light, where does all the energy it ...
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109
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Do black hole horizons always increase?
In asymptotically flat spacetimes, the area of a black hole event horizon must always increase, provided the Null Convergence Condition is followed ($R_{\mu\nu}k^{\mu}k^{\nu}\geq0$ for all null ...
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What's the current theory on final stages of black hole decay? [duplicate]
Okay, firstly, I know this question was asked here 11 years ago. And I know the correct answer is that we don't know because we haven't run the experiments and don't have a solid theory of quantum ...
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