All Questions
16
questions
3
votes
3
answers
182
views
Photonic black holes
"Can a photon turn into a black hole?" - usually the answer to this question is - it can't, because it has zero rest mass. However, when we derive the Schwarzchild Metric initially the $2M$ ...
- 1,161
4
votes
2
answers
341
views
Frequency of the photon in general relativity
There is an observer at ($r,\theta, \phi$) outside of the Schwarzschild blackhole. A beacon is falling into the black hole along $r$ coordinates of the metric and is emitting radiation. At $r_{em}$, ...
- 299
4
votes
3
answers
262
views
What does it exactly mean when we say that a photon or light is "frozen" at the event horizon?
Objects on this site are said to "freeze" at the event horizon, but what about photons themselves?
I have read this question:
At the event horizon $v_{eff} = 0$ and the light beam is frozen ...
- 29k
1
vote
0
answers
35
views
Do anti-parallel photons affect each other gravitationally? [duplicate]
We know that two parallel photons have no gravitational effect on each other because they never pass through each other's light cone. The question is, what happens to anti-parallel photons? It ...
- 804
-5
votes
2
answers
144
views
Does the fact that light (photons) are bent by a sufficiently big mass prove that a quantum theory of gravity doesn't exist?
As is proven, light can be bent by a heavy mass in the context of classical General Relativity. In a quantum theory of gravity, the gravity field around a heavy mass consists of a condensate of (...
3
votes
2
answers
227
views
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?
- 182
3
votes
2
answers
2k
views
Does GR prove light is corpuscular?
General Relativity predicts the bending of light due to gravity. But, does this explanation require light to be corpuscular? Can the EM waves of classical electromagnetism be bend in Einstein's ...
- 2,918
1
vote
1
answer
348
views
Would photons "riding" a gravitational wave appear different to an observer?
Gravitational waves travel at the speed of light. A photon travelling in exactly the same direction as a gravitational wave will therefore remain in exactly the same position relative to the wave - at ...
0
votes
2
answers
179
views
Is the Light REALLY bent?
I've learned that always, the light go straight. The as Einstein's gravitation therory, the light can be bent in bented space-I mean, curved space.
Actullay, I think that if we in the space which ...
- 29
0
votes
1
answer
69
views
Effects of gravitational waves on light
My understanding is that light is curved by curvature in space-time lattice (that's why it can't escape a black hole, it is just too curved: I may be wrong). So how is light influenced by ...
- 737
2
votes
2
answers
203
views
Shouldn't a photon traversing the vacuum always be associated with a gravitational wave?
In perusing the linearized Einstein equation, it appears that even a classical electromagnetic plane wave would always have to be associated with a tensor perturbation to the background spacetime. ...
- 2,847
1
vote
3
answers
2k
views
Why can't light escape a blackhole? [duplicate]
Gravity attracts objects which have mass right. We know that light is massless so why does a black hole's gravity attract light?
- 1,925
2
votes
1
answer
112
views
Is there any difference in radiation pressure for two observers in different gravitational potential?
Suppose that a light beam is shone upwards from surface of a planet. So, due to gravitational redshift, the frequency of the light perceived by observer far from the surface will be lower than that ...
- 91
18
votes
3
answers
672
views
Comparing predictions and reality for the gravitational attraction due to light beams
While doing some on-the-side reading, I stumbled across this question: Do two beams of light attract each other in general theory of relativity?. Great question and a great, easily understandable ...
- 24.5k
10
votes
2
answers
973
views
Do photons and cosmic rays radiate energy through gravitational waves? If not, why not?
Due to the mass-energy equivalence, both matter and EM radiation bend spacetime, and both are capable of forming singularities (black hole, white hole/kugelblitz). In light of this, why do photons ...
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