“When you look at the calculation, it's amazing that every time you try to prove or disprove time travel, you've pushed Einstein's theory to the very limits where quantum effects must dominate. That's telling us that you really need a theory of everything to resolve this question. And the only candidate is string theory.”
“For bedtime reading, I usually curl up with a good monograph on quantum physics or string theory, my specialty. But since I was a child, I have been fascinated by science fiction. My all-time favorite is 'The Foundation Trilogy,' by Isaac Asimov.”
“I vowed to myself that when I grew up and became a theoretical physicist, in addition to doing research, I would write books that I would have liked to have read as a child. So whenever I write, I imagine myself, as a youth, reading my books, being thrilled by the incredible advances being made in physics and science.”
“Humans are natural-born scientists. When we're born, we want to know why the stars shine. We want to know why the sun rises.”
“Chemistry is the melodies you can play on vibrating strings.”
“Years ago, I picked up figure skating. How hard could spins and jumps be, I thought? It's just applied Newtonian physics. After repeatedly falling on my rear end, I realized it was harder than I thought. But it had an upside. That is how I met my wife, who was ice dancing at the Rockefeller Center ice rink.”
“Aging is basically the build-up of error: error at the genetic level, error at the cellular level. Cells normally repair themselves; that's why you heal when you get a cut. But even the mechanism of repair eventually falls apart.”
“Even if we mortgage the next 100 years of generations of human beings, we would not have enough energy to build a Death Star.”
“You can mass-produce hardware; you cannot mass-produce software - you cannot mass-produce the human mind.”
“You have to have a cultural ethic that allows for making mistakes. It cannot be that just because you make mistakes, you're out. You have to make mistakes in order to innovate.”