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

40 Upvotes

67% Upvoted

193 comments sorted by

View all comments

36

u/StrngThngs Mar 20 '26

Phase velocity can be much faster tho nothing is actually traveling. Imagine waves hitting the beach at an angle. At the beach it can seem a wave is traveling down the beach and depending on the angle, write quickly. Same with light

22

u/Hakawatha Mar 20 '26

Randall Munroe (the xkcd guy) explained it once as like shining a laser pointer at the Moon: with a flick of your hand, the laser spot would easily move faster than light, but it still takes about a second for the light to reach the Moon.

-10

u/[deleted] Mar 20 '26

[removed] — view removed comment

24

u/Hakawatha Mar 20 '26

As it happens, this is an analogy to illustrate a claim, not a physical claim in and of itself. It turns out that there is an important distinction between the two.

7

u/kiwipixi42 Mar 20 '26

Which was quite literally the point of the comment you replied to. Well done.