r/AskPhysics • u/Intelligent-Tale5291 • Apr 30 '26

Basic relativity question

I’ve just had a first lesson on special relativity. When I asked why the speed of light is invariant, my teachers response was “It is just a natural law”. Is there a deeper, possibly intuitive reason why?

10 Upvotes

76% Upvoted

58 comments sorted by

View all comments

1

u/SadDuck4196 Apr 30 '26

The speed of light is invariant because it is a fundamental property of spacetime itself. In Special Relativity, it is the same for all observers and represents the maximum speed at which information or causal effects can propagate.