All Questions
Tagged with black-holes photons
100
questions
7
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882
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Photon Escape Angle From Black Hole
Consider a photon source emitting photons near the surface of a Schwarzschild black hole.
What angle, as a function of the source's radius from the event horizon, must the photons be emitted at such ...
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1
vote
1
answer
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Can we build a synthetic event horizon?
If we imagine ourselves to be a civilization capable of manipulating very heavy masses in arbitrary spatial and momentum configurations (because we have access to large amounts of motive force, for ...
- 1,719
5
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2
answers
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Kinetic energy of a photon and Schwarzschild radius
I have read here, that $\frac{1}{2}mv^2$ must not be applied on a photon ever.
If i want to calculate escape velocity $v_e$ i need to use $\frac{1}{2}mv^2$ because we say that kinetic energy (...
- 2,585
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What happens to the wavelength/frequency of a photon as it passes through an event horizon?
I've asked a similar question about photons and black holes but wanted to rephrase it more specifically, so here goes...
Ever since I learned how a photon's wavelength and frequency are indivisibly ...
- 181
4
votes
1
answer
698
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What is a virtual photon pair?
When describing a black hole evaporation in the hawking black body radiation it is usually said that is due to a virtual photon pair, is it this what happens? And what is virtual photon pair, does the ...
- 1,047
3
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2
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Why do photons add mass to a black hole?
Why do photons add mass to a black hole?
When photons are taken irreversibly into a black hole does the mass of the BH increase?
- 1,241
7
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2
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Computing the path of photons near a black hole
For a simulation, I want to compute the path that light follows near a black hole.
Non-relativistically, a massive point particle in a central newtonian gravitational field follows either an ellipse, ...
- 1,155
4
votes
2
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What happens to a photon in a black hole?
Assume a photon enters the event horizon of a black hole. The gravity of the black hole will draw the photon into the singularity eventually. Doesn't the photon come to rest and therefore lose it's ...
- 624
10
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1
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What happens to light that falls into a black hole?
When light enters a black hole, what happens to it?
I imagine the photons will either fall into the singularity, or the light will orbit just inside the event horizon indefinitely.
(Some background ...
- 826
2
votes
3
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Formation of black holes
If stars start with a finite density and light can escape from them, how can they be compacted to form a mass with infinite density which light cannot escape? The black hole will have the same mass as ...
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