The idea of a particle that races faster than light has long fascinated physicists. Known as the tachyon, it was originally dreamed up to help untangle paradoxes in quantum theory and relativity.

For over 100 years, two theories have shaped our understanding of the universe: quantum mechanics and Einstein’s general relativity. One explains the tiny world of particles; the other describes ...

(via Sabine Hossenfelder) The Andromeda Paradox, originally from Roger Penrose, is a brain-melting thought experiment that brings up the question of whether the future is still open or already fixed ...

Hello,<BR><BR><BR>I have been trying to think of a way to phrase this question so I do not appear to be a complete moron because I do not think I am but here goes.<BR><BR>Why is each observers frame ...

Time feels like the most familiar thing in the world, yet it hides one of physics’ hardest questions: why do we only remember the past and never the future, and why do broken eggs not leap back into ...

Have you ever made a mistake that you wish you could undo? Correcting past mistakes is one of the reasons we find the concept of time travel so fascinating. As often portrayed in science fiction, with ...

There’s an adage coined by [Ian Betteridge] that any headline ending in a question mark can be answered by the word “No”. However, Lorentz invariance – the theory that the same rules of physics apply ...

Have you ever made a mistake that you wish you could undo? Correcting past mistakes is one of the reasons we find the concept of time travel so fascinating. As often portrayed in science fiction, with ...

Have you ever made a mistake that you wish you could undo? Correcting past mistakes is one of the reasons we find the concept of time travel so fascinating. As often portrayed in science fiction, with ...