New posts in Reference Frames

Is time sped up when orbiting a black hole? Why? What does that mean?

Inertia on a rotating disc?

Deriving the law of reflection for a moving mirror in relativity

What is a moment?

What if two twins flew off in opposite directions and were reunited in a perfectly symmetric way, would they have aged same?

Non-constant angular velocity in orbit

How can a mechanical clock tick slower due to time dilation?

What does the accelerated twin see in the twin paradox?

How does the center of gravity work?

Physical intuition for why proper time is an invariant quantity