Linked Questions
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How does a photon experience space and time?
To an an external observer it appears that time has stopped for photon. But this relation is reflexive, so for an observer travelling with the photon it appears the universe has stopped everywhere.
...
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38
votes
5
answers
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What is the physical meaning of the affine parameter for null geodesic?
For time-like geodesic, the affine parameter is the proper time $\tau$ or its linear transform, and the geodesic equation is
$$\frac{\mathrm d^{2}x^{\mu}}{\mathrm d\tau^{2}}+\Gamma_{\rho\sigma}^{\mu}...
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23
votes
7
answers
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Is there a *geometric* explanation for why photons have no rest frame?
I've read the various threads on this site that talk about it being impossible for photons (or massless particles in general, really) to have a rest frame, and the answers all seem to boil down to &...
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vote
4
answers
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Frame of reference of a photon [duplicate]
I'm curious about the fact that it is impossible to consider a frame of reference where a photon is the reference itself (meaning a frame of reference where this photon can't move).
I looked for ...
user343933
0
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2
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How the world changes from the point of view of a photon [duplicate]
Imagine a universe without time, or more specifically without the Flow of Time. Everything will be a 2D projection and nothing more. No movement, no interaction, and in other words no Change.
But our ...
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0
votes
3
answers
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Can an object theoretically reach, or exceed the speed of light? [duplicate]
I'm sorry if this is a naïve question, but it's been bugging me for a bit. If a spacecraft were traveling in a perfect space with unlimited fuel, could it not, assuming it is not influenced by other ...
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-5
votes
2
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How can light have a speed when it devies what speed is?
For us to measure any movement, the "something" has to have a different position to some reference frame. now speed is defined by the amount of changed position( which we can tell by the ...
-1
votes
1
answer
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One of the consequences of travelling faster than light [closed]
Usually when talking about material particles exceeding the speed of light they talk about being able to travel to the past and that breaking causality. There's another particular case which they don'...
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2
answers
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Is spatial distance objective?
While reading some papers on Einstein's theory of relativity, seeing how the flow of time is not the same for everyone, a doubt occurred to me:
Let us imagine a photon moving in a well-defined space ...
-1
votes
3
answers
68
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Special relativity time dilation [duplicate]
According to special relativity time should stop for a particle moving at the speed of light, doesn't that mean that the particle stops moving as well? Then it is not going at the speed of light ...
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