relativity

Tag archives for relativity

Q & A: What is Energy?

Let me set the scene for you: I’m fresh off my Ph.D., teaching introductory physics at the University of Wisconsin. I’m trying to demonstrate how to turn potential energy into kinetic energy, and so I ask this simple question: What is Energy? And I get a stunned silence back from the room. One of those…

Faster-than-light travel: is it possible?

Apparently, this is becoming a good place for people to get their questions answered! My friend Brian, recently wanted to know what the possibilities were for faster-than-light travel. Specifically, he was interested in it because he wants humans to do it. Brian: but otherwise how will we ever have a civilization like that in Star…