Disability can be no handicap.

Sometimes I wonder if I'm as famous for my wheelchair and disabilities as I am for my discoveries.

Exploration by real people inspires us.

The idea of 10 dimensions might sound exciting, but they would cause real problems if you forget where you parked your car.

There are plenty of dead scientists I admire, but I can't think of any living ones. This is probably because it is only in retrospect that one can see who made the important contributions.

As we shall see, the concept of time has no meaning before the beginning of the universe. This was first pointed out by St. Augustine. When asked: What did God do before he created the universe? Augustine didn't reply: He was preparing Hell for people who asked such questions. Instead, he said that time was a property of the universe that God created, and that time did not exist before the beginning of the universe.

The boundary condition of the universe is that it has no boundary.