Faster Than Light Tachyons, Causality and Tacos

This has poor audio. Please see the remastered version linked below.

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?

0:00 Introduction
0:25 Faster than Lightspeed Travel
1:12 Too Bad....
2:30 The Two Principles of Special Relativity
6:21 The Principle of Causality
11:09 Galilean Relativity in Sketch Form
16:30 Galilean Relativity: Speeds Add Together
18:02 Galilean Relativity: Do Speeds Add Together?
19:42 No Longer Galilean Relativity
25:10 The Invariability of the Spacetime Interval
29:40 A Bouncy Light Clock
38:55 Consequences of Special Relativity
39:53 What about Tachyons?
42:14 Tachyonic Anti-Telephone
49:17 Special Relativity Demands Causality
49:55 Time Dilation: Moving Clocks Run Slower