All Questions
Tagged with black-holes photons
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Do light particles have thrust? [duplicate]
I understand that nothing is faster than light and that it can not escape a black hole. However, light particles may be fast, but perhaps it can't escape a black hole due to it's lack of thrust power? ...
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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 ...
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Would a black hole act as a particle accelerator between the photon sphere and the event horizon?
I'm trying to understand the behavior of photons between the photon sphere and the event horizon. Here is what I think I understand so far :
the radius of the PS is 1.5 times the Schwarzschild radius
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The effect black holes have on light
We all know that light loses its energy when it is moving through expanding space and time. And sense a black hole can be summed up to a super compressed space time, shouldn't that mean that a photon ...
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Whats the difference between the Photon Sphere and the Marginally bound orbit?
Whats the difference between the Photon Sphere and the Marginally bound orbit?
Why does photon sphere have a radius of 1.5Rs, while the Marginally bound orbit has a radius of 2Rs?
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In theory (because light can still enter a black hole) if you are inside of the event horizon, could you see outside of it? [duplicate]
To my limited knowledge, it should be possible for you to see from inside of a black hole. Is this true, or am I missing something?
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Radial motion of a photon in Schwarzschild spacetime
For photon worldlines in the equatorial plane of the Schwarzschild coordinate system ($\theta=\frac{\pi}{2}$) in Schwarzschild space-time, the metric equation is given by,
$$-\Big(1-\frac{2GM}{r}\Big)...
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Orbital Photon Speed at the equatorial plane of a rotating black hole
I've been trying to calculate $d\phi/dt$ of photons orbiting a Kerr black hole (Kerr metric in Boyer-Lindquist coordinates) on the equatorial plane, both counter and along with its rotation. So I used ...
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Can black holes move at the speed of light? If so, what would its curvature look like? [closed]
This question has more to do with the curvature of moving bodies but I will first start with this.
If a photon has enough energy, then it could presumably become a black hole (kugelblitz). I see no ...
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Black holes bending light [duplicate]
Ok so I've been watching some videos about black holes but there is one thing I don't get: how can light be bent by black holes since photons don't have any mass?
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Regarding the radial motion of photons
Photons move on null geodesics and the equation of motion on equatorial plane after some algebra can be written as
$$e^{\nu}\dot{t}^2-e^{-\nu}\dot{r}^2-r^2\dot{\phi}^2 = 0$$
$\phi =0$ for the radial ...
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Photons past the event horizon [duplicate]
What would happen if, beneath the event horizon, a photon was emitted outwards along the radius of the black hole? It's speed can't change to any observer in any reference frame, but it surely cannot ...
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Why is a black hole referred to as massive? [duplicate]
I am reading Brief Answers To The Big Questions by Stephen Hawking. In the very first chapter he writes,
A typical black hole is a star so massive it has collapsed on itself. It's so massive that not ...
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If an event horizon never forms for an outside observer, then what do (or don't) we see in the middle area on this real image of an actual black hole?
There are a lot of questions about the m87 image on this site, non of them actually answer my question.
I have read this question:
Does an expanding event horizon "swallow" nearby objects?
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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 ...
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