Michio Kaku

We have to realize that science is a double-edged sword. One edge of the sword can cut against poverty, illness, disease and give us more democracies, and democracies never war with other democracies, but the other side of the sword could give us nuclear proliferation, biogerms and even forces of darkness.

In the 1950s, we had all these B-grade science-fiction movies. The point was to scare the public and get them to buy popcorn. No attempt was made to create movies that were somewhat inherent to the truth.

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.

I have nothing against investment banking, but it's like massaging money rather than creating money. If you're in physics, you create inventions, you create lasers, you create transistors, computers, GPS.

I have nothing against investment banking, but it's like massaging money rather than creating money.

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.

When you come up with a theory, you fall in love with the beauty the simplicity and elegance of it. But then you have to get a sheet of paper and pencil and crack out all the details. Hundreds and hundreds of pages. Because you have to prove it.

We do spend too much time on the telephone, and you know something? We love it.

I get paid to do what I love. If you understand physics, the foundation of the atomic theory and relativity, you understand how the future is going to unfold. You understand what things are not possible. You understand why things work. I get paid to do what I love the most, and that is to work on the Unified Field Theory and to see the future.

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.

I realized very early in life what my abilities and limitations were, and foreign languages was definitely one of my limitations. With strenuous effort, I just barely passed my French class at Harvard so I could graduate.