You have to be careful when you use beauty as a guide. There are many theories people didn't think were beautiful at the time but did find beautiful later—and vice versa. I think simplicity is a good guide: The more economical a theory, the better.

Our hypotheses are initially rooted in theoretical consistency and elegance, but...ultimatel y it is experiment not rigid belief that determines what is correct.

Travel at faster than the speed of light certainly can have dramatic implications that are difficult to understand, such as time travel.

Maybe dark matter is denser than we usually assume, kind of like the Milky Way plane.

We certainly don't yet know all the answers. But the universe is about to be pried open.

You can be only a modest distance away from the gravity brane, and gravity will be incredibly weak.

Although I was first drawn to math and science by the certainty they promised, today I find the unanswered questions and the unexpected connections at least as attractive.