Next week, Prof. Shaul Hanany will lie on a bed of nails while someone takes a hammer and smashes a cement block on his stomach. But he's not worried. Really. He knows that physics is on his side.

For many, it's the start of a new semester of physics labs. That means there are new students in that introductory course. Of course, no one is really 100 percent ready to start these labs---but ...