New posts in Relativity

Space-like and time-like: where do the names come from?

Does velocity or acceleration cause time dilation?

How to prove the raising/lowering indices operation?

Can a free particle absorb/emit photons?

Proper time for an accelerating object

In coordinate-free relativity, how do we define a vector?

Why do clocks measure arc-length?

What is the speed of time?

Deriving the action and the Lagrangian for a free massive point particle in Special Relativity

How is light affected by gravity?