All Questions
Tagged with black-holes photons
25
questions
19
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3
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How close does a photon have to get to a black hole to do a full loop?
How close does a photon have to get to a black hole to do ONE full loop? By full loop I mean it curves once around the black hole, and then it ends up on the same trajectory as it was one before it ...
- 2,908
1
vote
3
answers
399
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Speed of light originating from a star with gravitational pull close to black-hole strength?
Imagine you have a star which is on the brink of turning into a black hole. Lets say it is infinitely close to become a black hole, but not there yet.
Since there is no event horizon, but a great ...
10
votes
1
answer
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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
4
votes
3
answers
1k
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Photons straight into black hole
What happens to a photon shot straight into a black hole? Does it gain infinite momentum before it crosses the horizon? If it has a finite momentum going in, then it would seem that a photon of the ...
2
votes
3
answers
5k
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How much energy does a photon need to form a black hole?
I was wondering if it is possible for a single photon to form a black hole if it has a small enough wavelength.If so, what would this wavelength be? I came across this question because I am reading ...
- 3,997
9
votes
2
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Rainbow Blackhole?
Can white light be broken into its component colors when gravitationally shifted by a black hole, in a manner similar to what a prism does?
http://www.physics.utah.edu/~bromley/blackhole/index.html
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5
votes
1
answer
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Photon "stuck" on the event horizon of a black hole
According to what I've read on special relativity, $c$ is the speed limit for every object in the universe, and according to Einstein, an object's speed through the three spatial dimensions plus its ...
- 101
4
votes
2
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2k
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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
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
1
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3
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522
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Photons emitted at the event horizon?
While looking through the questions, a came across a section about black holes. I immediately though; what would happen if an atom is orbiting a black hole and emitted a photon perpendicular to the ...
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18
votes
5
answers
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Could an infinite number of photons fit into a finite space?
As photons are quantum particles and basically waves in a quantum field, could an infinite number of photons exist in a closed space described by finite numbers? Does the answer to this apply to other ...
- 401
12
votes
1
answer
327
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Can gravitational waves orbit a black hole?
Assume (for the sake of simplicity) a Schwarzschild black hole (non-rotating, non charged). This black hole has a photon sphere in $r=1.5r_s$, where photons may travel in a circular orbit.
Will a ...
- 653
7
votes
4
answers
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 ...
- 73
5
votes
2
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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
4
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2
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If photons have no (rest) mass, why would black holes attract light? [duplicate]
I was told that photons have no (rest) mass. However I thought that black holes are called "black" because no light can go escape the gravity force in their vicinity. I somehow think that, if light is ...
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