Linked Questions
61 questions linked to/from Does a photon in vacuum have a rest frame?
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Photons moving relative to photons [duplicate]
I know we can't move at the speed of light, but if we were to travel on a photon how fast would we see other photons going? The speed of light is constant... So do photons see other photons moving at ...
user24082
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1
answer
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How can a photon "stop"? What does its world line look like? [duplicate]
Einstein famously made a thought experiment: what would he see if he sat on a beam of light? His answer was -- it's impossible. Owing to him being a body with mass, he can never ever reach light speed ...
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4
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Photon Emission/Absorbsion from the Photons Perspective [duplicate]
First some assumptions.
1) Photons travel at the speed of light.
2) From the photon's reference spacetime is contracted to 0 length in the direction of photon travel.
3) From the photon's reference ...
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2
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Why isn't it valid to consider a photon at rest with everything else moving at $c$? [duplicate]
Since relativity postulates that the laws of physics are invariant in all inertial systems, why can't photons have an inertial reference frame?
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Does a photon not having a reference frame result in logical inconsistency? [duplicate]
So, I know that SR makes two statements.
One is the first assumption it has:
"Speed of light is the same with respect to all reference frames".
Second, the statement:
"A photon cannot have a ...
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4
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Does light in vacuum actually travel at the speed of light? [duplicate]
I know my question sounds like a joke (and I suppose on some level it is) but I'm confounded by the following:
As the thought experiment goes, if I'm in a spaceship flying rapidly the people on earth ...
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1
answer
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According to Einstein & Brian Greene, does the photon remain stationary in the fourth dimension? [duplicate]
According to Einstein and Brian Greene, does it logically follow that the photon remains stationary in the fourth dimension?
In An Elegant Universe, Brian Greene writes:
“Einstein found that ...
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3
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Are photon rest frames distinguishable from other inertial frames? [duplicate]
The principle of relativity suggests that all inertial frames are indistinguishable. But if I consider the rest frame of a photon (i.e. an IRF traveling at speed $c$ w.r.t. me), then won't it be ...
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2
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2
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Is it possible for a photon to be at rest? [duplicate]
I know it doesn't really make sense if looking at the photon from the wave point of view, but is there any law of physics which prohibits a photon from stopping completely? Thanks.
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How can photon have wave properties if they travel at the speed of light? [duplicate]
I am not a physicist so please excuse me if this is a dumb question.
As far as I understand Relativity, as observer (in this case a photon) travels at the speed of light, time stops. So how can the ...
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3
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From the photons perspective [duplicate]
Probably been answered but couldn't find the answer.
From the perspective of a photon:
- For the photon to travel from body A to body B would take 0 secs.
- The universe would be one point in "...
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What is the velocity of a photon with respect to another one? [duplicate]
When light comes from a source, there are numerous photons associated with the energy packets.
Now, what is the velocity of a single photon with respect to another photon coming form the same source i....
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1
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Can a frame of reference travel with the speed of light? [duplicate]
I read that nothing with mass can travel at the speed of light. Therefor one can not ask what happens when an observer in a car moves with the speed of light. But, is it possible for a frame of ...
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2
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If a massless observer is going at the speed of light, what speed will it measure of a light beam going parallel to it? [duplicate]
If a massless observer is going at the speed of light, what speed will it measure of a light beam going parallel to it?
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Do photons exist from point of view of photon? [duplicate]
If photons are travelling with speed of light, it means that time is stopped for photons and there is no any distance in the Universe for them. So, does it mean that photons do not exist? From the ...
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