Physics & Math / String Theory

I'm really concerned about it. If we don't do it now, we'll probably never do it. We've built up the technology; we're at a point where if we don't continue, we'll lose that expertise, and we'll have to start all over again. True, it's expensive, but at the end of the day I believe it will be worth it. It makes a difference in terms of who we are, what we think, how we view the world. These are the kinds of things that get people excited about science, so you have a more educated public.

One of the amazing things about your work is that so much of it comes straight from your imagination, not from rooting around in the laboratory. It seems very much like chalk-and-blackboard research.

Right, the blackboard. Those are the things that seem to strike people, that we have blackboards with equations all over them and that we are talking to each other a lot; we're not just going into our offices and ignoring the rest of the word. But we do just go and think sometimes. Once you're really focused, if you get jogged out of it, you have to go back and really reestablish that. It's like Fred Flintstone and his bowling ball: You don't want to interrupt someone when they're in that state. Then again, sometimes we're just talking and writing together on a piece of paper, and sometimes we're at that blackboard putting ideas back and forth. Our work is all those things. It's reading what other people have done, trying to puzzle through something, getting stuck, getting unstuck, trying to find different ways around a problem.

You don't exactly fit the image of the graying, tweedy professor. Does being a young woman in a male-dominated field carry special responsibilities?

If only I was still young! [Laughs] I thought maybe I'd make it all the way through an interview without having to talk about this. But, yeah, I think it does. I'm probably more careful, and probably I spend more time on this particular issue. Also, in writing my book, I felt it had better be good, because there aren't that many women in the field, and I thought it would be subject to extra scrutiny. So there is extra responsibility; the flip side is that potentially there's extra reward if it draws a more diverse group into physics.

Outside your own area of research, where do you see the most vibrant things happening in science today?

Neuroscience is exciting. Understanding how thoughts work, how connections are made, how the memory works, how we process information, how information is stored—it's all fascinating. Experimentally, though, we're still rather limited in what we can do. I don't even know what consciousness is. I'd like someone to define consciousness.

Many people would say physics has a long way to go too. Does it bother you that the things you're excited about now may seem quaint as soon as someone comes up with a better theory?

True, we haven't found all the answers, but we've found some and we're finding more. The fact that we don't know everything doesn't mean we know nothing. People have asked me, "Why bother, if you don't get final answers?" I said, "If someone gave me a dessert, and I knew it wasn't the best dessert ever, I would still be really happy to eat it and wait for the next one."

Will physics ever be able to tackle the biggest questions—for instance, why does the universe even bother to exist?

Science is not religion. We're not going to be able to answer the "why" questions. But when you put together all of what we know about the universe, it fits together amazingly well. The fact that inflationary theory [the current model of the Big Bang] can be tested by looking at the cosmic microwave background is remarkable to me. That's not to say we can't go further. I'd like to ask: Do we live in a pocket of three-dimensional space and time? We're asking how this universe began, but maybe we should be asking how a larger, 10-dimensional universe began and how we got here from there.

This sounds like your formula for keeping science and religion from fighting with each other.

A lot of scientists take the Stephen Jay Gould approach: Religion asks questions about morals, whereas science just asks questions about the natural world. But when people try to use religion to address the natural world, science pushes back on it, and religion has to accommodate the results. Beliefs can be permanent, but beliefs can also be flexible. Personally, if I find out my belief is wrong, I change my mind. I think that's a good way to live.

So does your science leave space for untestable faith? Do you believe in God?

There's room there, and it could go either way. Faith just doesn't have anything to do with what I'm doing as a scientist. It's nice if you can believe in God, because then you see more of a purpose in things. Even if you don't, though, it doesn't mean that there's no purpose. It doesn't mean that there's no goodness. I think that there's a virtue in being good in and of itself. I think that one can work with the world we have. So I probably don't believe in God. I think it's a problem that people are considered immoral if they're not religious. That's just not true. This might earn me some enemies, but in some ways they may be even more moral. If you do something for a religious reason, you do it because you'll be rewarded in an afterlife or in this world. That's not quite as good as something you do for purely generous reasons.