All Questions
Tagged with black-holes photons
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If the photon is the force-carrier for the electromagnetic force, how does the electric charge of a black hole escape the event horizon? [duplicate]
When people speak of the electric charge of a black hole, do we actually mean it affects things outside of the event-horizon or is it just a property it has?
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Trajectory of a photon beyond the event horizon
So this random question popped up in my mind. As we know the photons get deflected if they pass in the vicinity of a black hole. At the event horizon(right before it), they form the photon sphere. The ...
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What is the Critical impact parameter for photons of a black hole?
What is the "Critical impact parameter" for photons of a Black hole with a Radius $r$?
Here I'm defing the Critical impact parameter $C$ as the value such that.
A photon with an impact ...
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Can a photon be frozen (relatively stationary) in space? [closed]
There are a lot of questions on this site about photon speed, none of them answer my question:
Why and how is the speed of light in vacuum constant, i.e., independent of reference frame?
If ...
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Why is the Hamiltonian of a photon = 0?
I'm studying the motion of light near Schwarzschild black holes, and I was wondering why the Hamiltonian of the Schwarzschild metric $$H = - \left( 1-\frac{2M}{r} \right)^{-1} \frac{p_{t}^2}{2}+\left(...
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Can light of certain wavelengths stably orbit a black hole at the photon sphere?
I've recently learned that for a black hole, its photon sphere is an unstable orbit. Light either manages to escape from or fall into the event horizon, depending on how far away from the edge of the ...
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Photon near a black hole - find distance of closest approach from impact parameter
I have the equation relating the impact parameter $b$ to the distance of closest approach $R$.
$R^3 - b^2R + 1 = 0$
which can be solved in python. I have a given $b$ and have to find $R$. however, ...
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Greatest relativistc mass possible for a single photon [closed]
I have been told that photons can not be blue shifted to the point where they become black holes, although a photon with a Planck scale wavelength would also have a relativistic mass equal to a black ...
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Four-momentum of a photon emitted from an accretion disk
Consider a non-rotating compact object surrounded by a revolving accretion disk. A distant observer sees the disk in an edge-on position. The center of the disk may be taken as the origin of $r-\theta-...
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What happens to photons that have enough energy to form a Black Hole come together at a point in spacetime?
This answer to a question posed a few days ago made me wonder. I made this comment to the answer:
So if we place (as dense as possible) high power lasers on a sphere with a radius of, say, one ...
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Why doesn’t light escape a black hole? [duplicate]
When an object is squeezed to its Schwarzschild radius it becomes a black hole (made by density) and its mass does not change (its gravity doesn’t change), but if its mass doesn’t change (its gravity ...
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Why energy matters for light to escape event horizon?
I like to know why photon with sufficient energy can avoid being pulled into the event horizon? Most light will get trapped and forms into photon sphere while some can escape, isn't light supposed to ...
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227
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Can a photon circle a black hole indefinitely?
Does a photon lose energy or redshift as it circles?
Will it's wavelength be the rest wavelength with centripetal and gravitational forces exactly cancelling?
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The event horizon of a black hole supposes an absolute zero in some field?
Based on the Schwarzschild black hole theory, if the gravitational pull of the singularity were to equalize the energy that a photon has by approaching the event horizon from a special angle, would it ...
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Pulling of Light by a Black Hole? [duplicate]
We all know that light has no mass at all. Yet we say that the gravitational pull of a Blackhole within Schwarzschild radius doesn't let light to pass. If the light has no mass, how can it experience ...
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