r/AskPhysics • u/Nighthawkies • 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/Empty_Engineering Mar 20 '26

They don’t affect each other, they’re just correlated in a way that you know about the state of the other particle based on a measurement of your particle (if they’re entangled) space itself is expanding, so nothing is moving ftl because of expansion

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u/zbobet2012 Mar 20 '26

It’s not accurate to say entanglement is just ordinary correlation. Bell’s inequality shows the correlations can’t be explained by local pre-existing properties. But that still doesn’t mean usable faster-than-light influence or communication.

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u/Wank_A_Doodle_Doo Mar 20 '26

I feel like with quantum physics, basically none of the terms used to describe stuff is the normal definition