What would it look like to travel faster than a photon?

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cragar said:
in a nuclear reactor neutrons travel faster than photons in the water , this is called cerenkov
radiation , although someone will probably say that photons only appear to slow down in different media and that they always travel at c .
and I might add that they can slow down light to like 38mph by passing it through an Einstein -Bose condensate , so in a sense you can travel faster than a photon , but not c .

This is not quite relevant to the thread, since we're talking about speed of photon, and not group velocity of light.

Zz.
 
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elven said:
According to the Special Theory of Relativity, going faster than light is not possible, it would require an infinite amount of energy, although tachyons, etc are exceptions. Unfortunately, tachyons were never proven to actually exist, therefore, for now, we can say it is impossible to travel faster than the speed of light.
Only for things that have mass. There are mass-less objects that aren't constrained by this rule.
 
Not true. Massless objects cannot go faster than light either.
 
I have better make a disclaimer: I am not a physicist. But I might be able to help you on comprehending why it is not possible to go any faster than c according to Einstein.

SR tells us that the faster you move, the more space contracts in the direction of your travel. Distances simply get shorter in front and behind you. When you reach the speed of light in vacuum the contraction of space in the direction you travel is absolute. There is no distance left. Everything in front of you and behind you in the entire universe is right where your are. So you arrive instantly. It is hard to see that it would be possible to reach somewhere any faster than instantly, isn't it?

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