Faster Than Light Tachyons, Causality and Tacos (Intro Astronomy module 3, lecture 11)

This is part of my complete intro Astronomy class. If you want to watch all the videos in the correct order, please visit my website at What happens when you go faster than light? Can you go faster than light? (well, no, but let’s chat anyway). And how do we know that we can’t go faster than light? Why does going faster than light mean traveling into the past?