Brian Greene

One of the strangest features of string theory is that it requires more than the three spatial dimensions that we see directly in the world around us. That sounds like science fiction, but it is an indisputable outcome of the mathematics of string theory.

The central idea of string theory is quite straightforward. If you examine any piece of matter ever more finely, at first you'll find molecules, atoms, sub-atomic particles. Probe the smaller particles, you'll find something else, a tiny vibrating filament of energy, a little tiny vibrating string.

The thrill of a photo-realist painter is if you get really close to the painting, it looks just like a photograph. Whereas in my case, if you get close to my paintings, they totally fall apart - so I'm about as far from a photo-realist as it gets.

Having a Congress with a more diverse educational and professional background would serve the country well. And given the budget challenges facing America today, we might benefit from a few more cold, calculating problem solvers, and fewer courtroom impresarios.

I doubt very much that the chief executives of any of the Fortune 500 corporations can name five edible plants, five native grasses, or five migratory birds within walking distance of their homes, or name the soil series upon which their house sits. And I would contend that if you don't know where you are, you are in fact nowhere at all.