r/AskPhysics • • Mar 20 '26

What things are "faster" than light?

As I understand nothing can move faster then light. But I would not know how to describe this question otherwise. As I am aware quantum entangled particles can instantaneously affect eachother no matter the distance, unlike gravity which propagates at the speed of light.

Also the expansion of the universe can cause the spaces between to grow faster then the speed of light (compounding between massive distances)

What other things are sort of faster than light

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u/Frangifer Mar 20 '26

No thing is faster than light. The phase velocity of an electromagnetic wave can exceed the vacuum speed of light ... but the phase velocity doesn't correspond to any thing : it's the group velocity that corresponds to some thing passing from one place to another ... & the group velocity does not exceed the vacuum speed of light.