All Questions
Tagged with gravity electromagnetic-radiation
58
questions
7
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1
answer
747
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Can gravity radiate?
In electromagnetism, when a charge accelerates, it emits radiation. We know this because we can write the retarded potentials, apply $\vec E=- \nabla V-\frac{\partial \vec{A}}{\partial t}$ and $\vec B=...
- 1,616
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2
answers
43
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Stars that have fairly high gravitational redshift and calculation of their surface temperature by Planck emition spectra?
How high can the ratio between gravitational redshift and planck emition spectra be depending on the mass of the star so by how much this gravitational redshift could elongate the Planck spectra of ...
- 2,255
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votes
2
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124
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Does gravity affects electromagnetic waves? Or electromagnetism affects gravity?
I'm confused about the relationship of electromagnetism and gravity, or are they even related?
It has been said the electromagnetic field produces a gravitational field, and so, there is no gravity if ...
0
votes
0
answers
21
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Charged particles deflected by gravitational and magnetic fields
I am trying to better understand one of my previous questions, and another.
Charged particle in uniform Magnetic field
Does a charged particle orbiting Earth radiate?
https://en.wikipedia.org/wiki/...
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-4
votes
2
answers
103
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Speed of light affected by gravity or frame dragging effect
If we do not really 100% know how light works as a oscillation we also do not know is its speed indeed constant no matter is there a space or space-time motion that can affect it. Could a device that ...
- 2,255
2
votes
2
answers
387
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Is there a relation between spacetime curvature and radiation?
To my understanding, the curvature of spacetime is determined by the stress-energy tensor.
I was wondering if we could calculate some of those components using radiation.
Is it possible that objects ...
-3
votes
3
answers
229
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Why is light not affected by gravity?
If a rocket needs to go to mars, it needs to go through a specific trajectory. But i can see the sun straight where it is, so light does not obey gravity?
- 121
3
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1
answer
214
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Deviation of light rays in a scalar gravity theory (simple modification of Nordström theory)
I'm considering a simple scalar theory of gravity in Minkowski spacetime, which isn't exactly the same as the old Nordström theory. The scalar gravity field $\phi$ and the electromagnetic field $A_a$ ...
- 7,592
2
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2
answers
189
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Does the frequency of light have any effect on gravitational lensing? [duplicate]
General relativity considers gravity as the curvature of space-time instead of a force. Therefore, what is bent around an astronomical object is the space-time itself. The light just follows the path ...
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3
votes
1
answer
107
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Gravitational wavelength shift of microwave background radiation
I can't find this precise question answered. It is basically a two part question.
Would the microwave background radiation, as well as light travelling to us from stars in an expanding universe ...
- 533
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votes
1
answer
29
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Red shift for an observer outside the gravitational field
Assuming there are no forces around,consider the situation:
A multi storey laboratory is accelerating in free space, for convenience say vertically. In it a light pulse is generated. The people in ...
- 1,270
15
votes
2
answers
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Is there a gravitational analogue of a classical Rutherford-atom?
In a Rutherford-atom, the electron classically emits EM radiation on an average rate of,
$$
-\frac{dE}{dt}=\frac {\omega^4 e^2 R_0^2}{3c^3(4π\epsilon_0)}
$$
Where $\omega$ is the angular frequency, $...
- 421
1
vote
0
answers
35
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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
1
vote
2
answers
189
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Does it take work to bend light?
We all know that light always travels in a straight line. Would it not then stand to reason that changing the path of light requires energy? If so, would this not violate Newton's laws of motion if ...
- 804
7
votes
2
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483
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Do gravitational waves travel always in a straight line (along a geodesic) like EM waves?
There are a lot of questions and answers on this site about light traveling in straight lines in vacuum (following a geodesic). And there are a lot about both EM and gravitational waves traveling at ...
- 29k
2
votes
0
answers
52
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Are electromagnetic and gravitational waves the only known types of waves that can travel in empty space? [duplicate]
Besides electromagnetic and graviational waves, are there any other waves known to travel through empty space?
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1
answer
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Are very massive neutron stars highly streching wavelenghts of their emitted light?
Can be possible that more massive or more denser neutron stars stretch the wavelengths of their emitted EM-waves more than less massive and less denser neutron stars?
- 1,815
2
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0
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438
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Paradox of radiation of charged particles in a gravitational field
"Paradox of radiation of charged particles in a gravitational field" - Wikipedia ( Paper by a guy I forget the same of)
On wikipedia (reliable ikr), there is a paradox occuring between ...
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11
votes
3
answers
2k
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Can light cause gravity? [duplicate]
We know the following:
Two masses are attracted to one another, as represented by Newtonian gravity
$F = \frac{GMm}{R^{2}}$
Light is massless and bends in the curvature of space-time which can be ...
- 540
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3
answers
229
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Why does Light get caught by Gravity, when both are travelling at the Speed of Light?
Gravitational waves travel at the speed of light waves.
So then, why do light waves get caught by gravitational waves (eg, black holes)?
And if it is about the strength of the photon field, then why ...
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5
votes
2
answers
890
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Are photons affected by Earth's gravity? [duplicate]
Just wondering if the Earth's gravity affects the photons? We can obviously think about equivalent mass of photons by using de broglie relation and then use it to calculate force of gravitational ...
- 691
4
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1
answer
388
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Is there an Abraham-Lorentz force for Gravity?
The Abraham-Lorentz force in Electromagnetism is the recoil a charge experiences as it accelerates due to own emission of radiation.
The Newtonian theory of gravity is identical to that of ...
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2
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1
answer
117
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Can a free electron accelerating in a gravitational field absorb photons? [duplicate]
An 'free' electron accelerated in an electromagnetic field can both absorb and emit a photon. What about an election accelerating in a gravitational field?
Edit:
Some users have suggested that the ...
0
votes
1
answer
671
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How does black hole suck light? [duplicate]
I was asked the same by my friend. I said that gravitational attraction also occurs for high energy particles .
My friend said photon is not so very high energy particle which I found on net. He ...
- 1,149
3
votes
6
answers
922
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Does light’s deflection by a gravitational well vary depending on frequency or other properties of the wave?
I’m curious if the magnitude of the displacement of light by a gravity well is variable to any property of the photons (frequency, polarization, etc).
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1
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106
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Can my theory work for letting the swinging work?
This is my theory, will it stop after few hours? why would it stop? i have on top S to S to repel then i have N S to attract, to produce random force for the swing. Then i have large N N repel to push ...
- 97
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1
answer
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Photons and Black holes [duplicate]
A black hole is listed as "a region of spacetime exhibiting such strong gravitational effects that nothing—not even particles and electromagnetic radiation such as light—can escape from inside it" One ...
user172320
0
votes
2
answers
179
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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
1
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1
answer
202
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Strength of gravitational waves vs. electromagnetic waves
If the recent gravitational wave's energy had reached us as visible light, how bright would it have been? Stackexchange complains about the form and brevity of the question so i add something... if it ...
- 213
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votes
2
answers
395
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Light dispersion in gravitational theories
GR predicts no Ricci curvature in vacuum (or at least when we can ignore the cosmological constant). Would theories that violate this lead to observable light dispersion in solar system tests of ...
- 175
3
votes
0
answers
130
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Consequences of a stable geon
What would be the consequences be of a stable geon? What similiarity, if any, would it have to a naked singularity? What would a stable geon potentially look like, and what would the immediate ...
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4
answers
232
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Could gravitons just be low frequency photons?
James Clerk Maxwell determined that E-M waves propagate only at the speed of light, so considered that light may be an E-M wave. This was later shown to be correct.
Given that gravity also ...
- 2,637
1
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1
answer
272
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Ground state(s) of electron and dependence from temperature and gravitational potential
Reading this question What happens to an electron in a molecule once it has absorbed a photon and transitioned? it occurs the question to me is the ground state say of a hydrogen electron the only one?...
- 10.6k
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2
answers
343
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Gravitational waves vs. electromagnetic for telecommunications
Assuming it would be possible, what would be the advantages/disadvantages of manipulating gravitational waves for telecommunications versus using electromagnetic?
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15
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3
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616
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Can the question of a gravitationally accelerated charge radiation be tested experimentally?
I know that the question of radiation from a gravitationally accelerated charge has been discussed extensively at Does a charged particle accelerating in a gravitational field radiate?. Yet the ...
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1
answer
278
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'Hovering' light rays on the edge of a black hole
According to Prof. Hawking, light rays will 'hover' on the edge of a black hole. If this is true, and the light 'stops' on the edge, how can the electric/magnetic fields which, constitute the light, ...
- 470
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votes
2
answers
748
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Does light have mass? [closed]
Does light have mass?
If yes, will it exert force?
If no, then how are light particles are travelling at light speed?
If light doesn't have mass how is it attracted by gravitational force (black holes)...
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4
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0
answers
184
views
Will the photon wavelength fluctuate in the presence of a gravitational wave?
The microwave background is due to the expansion of the Universe where the wavelengths of radiations are stretched by spacetime.
As in the LIGO experiment, in the presence of gravitational wave, ...
- 1,995
1
vote
1
answer
261
views
Do electrons emit radiation due to gravity [duplicate]
Do electrons accelerating in the presence of a gravitational field radiate due to this acceleration?
- 6,015
1
vote
1
answer
381
views
Propagating higher order Hermite Gaussian modes. What are complex amplitude coefficients?
I've been tasked with writing a code (in MatLab, but I'm currently using Mathematica because I don't know MatLab %\ ...) to simulate the propagation of a Gaussian beam.
I don't really know anything ...
- 193
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3
answers
2k
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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
9
votes
3
answers
2k
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Why is it hard to detect a black hole
I've read in some texts that we can't directly observe a black hole in space because not even light can escape from its gravity. Some of the indirect observational methods mentioned are, gravitational ...
- 359
4
votes
2
answers
293
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Why does General Relativity predict more light deflection than Netwonian Physics?
If one looks at the limit as light's mass approaches zero, Newtonian Physics predicts a deflection of light (this can be seen by the fact that all objects are accelerate the same due to gravity.) ...
- 2,172
3
votes
1
answer
1k
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Electromagnetic radiation bending on Earth
Most articles say that a radiowave is able to propagate itself beyond the horizon because it is reflected off by the ionosphere (and the Earth itself).
But do radio waves also get bent according to ...
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1
answer
373
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Can light gravitationally affect itself?
Consider a electromagnetic wave in a vacuum. From my understanding of general relativity,
The wave has momentum, and thus generates a gravitational field in all directions.
The gravitational field ...
- 235
3
votes
1
answer
115
views
Accelerating masses lose energy?
If I understand this correctly, accelerating charges lose energy in the form of EM waves because they change the electric and magnetic fields, which "costs" energy. Does that mean that accelerating ...
- 812
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3
answers
276
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Why does gravitational lensing bend light rather than absorbing it?
I've read that gravitational lensing bends the light; I am a little confused about black holes and why lensing produces different results. Black holes absorb light whereas lensing should have also ...
- 111
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2
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225
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Has anyone checked whether the speed of light $c$ varies according to gravitation?
My physics is fairly basic, but I hope someone can answer without being too rude.
A transparent medium such as water or glass refracts light and also reduces its speed, so I was wondering whether ...
- 111
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2
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436
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Do electromagnetic fields gravitate?
It's well known that electromagnetic fields contains energy but do they gravitate?
When we talk about the composition of the universe it's now accepted that the 74% is dark energy, the 22% is dark ...
- 905
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votes
1
answer
1k
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What is the effect of gravity on gamma rays?
I read an article about a Gamma Ray burst linked to a black hole. How does high gravity fields affect gamma rays?
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