Wormholes - if you don't have something threading through them to hold them open, the walls will basically collapse so fast that nothing can go through them.

The jury is not in, so we just don't know. But there are very strong indications that wormholes that a human could travel through are forbidden by the laws of physics. That's sad, that's unfortunate, but that's the direction in which things are pointing.

My passion is to understand the non-linear dynamics of warped space-time, and the ideal venue for this is black-hole collisions.

I'm a real klutz computationally, so Mathematica is just ideal for me.

We'll have four different gravitational wave windows open within the next 20 years, and each of them will see something different. We'll be probing the birth of the universe with this. The so-called 'inflationary era' of the universe. We'll be probing the birth of the fundamental forces and how they came into being.

If you think that the distance from the Earth to the nearest planet where we could live comfortably... is being, like, from New York to Australia... what we've achieved so far, in going to the moon, that's about two-and-a-half inches. So that's the challenge.

The essential point is that, although coordinates are a powerful, and sometimes essential, tool in many calculations, the fundamental laws of physics can be expressed without the aid of coordinates; and, indeed, their coordinate-free expressions are generally elegant and exceedingly powerful.

I think that the future of the human race is to spread through the universe, and now is the time that we should be laying the foundations for that.

I wanted to be a snowplow driver when I was a kid. Growing up in the Rocky Mountains, that's the most glorious job you can imagine. But then my mother took me to a lecture about the solar system when I was 8, and I got hooked.

I got a lot of notoriety early on. Much of my career I was just trying to prove I was as good as the world thought I was.