January 11, 2012
Renowned theoretical physicist, author and professor Lawrence Krauss is visiting the Natural History Museum tomorrow to present a lecture titled “On the Universe and Nothingness.” Although tickets for this fascinating and thought-provoking talk are sold out (call the Residents Associates box office at 202-633-3030 to be placed on the wait list), we took the opportunity to speak with Dr. Krauss about his insights in physics, his role as a public intellectual and the wonder he sees in the universe.
Your book, A Universe From Nothing, attempts to explain where the universe came from and why it exists. What’s it like trying to explain these complex theoretical physics concepts to a general audience?
It’s always a challenge to do that, but it’s an exciting challenge. Because—it sounds trite, but it’s true—if you can’t explain something, you don’t really understand it. And I’ve often found in my writing that in the process of trying to write something to explain it to people, in a way, I’ve actually had new insights into the material, and it’s actually taught me things.
The other part about it is, I think that we hesitate to do this at our peril. Because one of the things that makes science so wonderful is that some of the most exciting ideas that humans have ever come up with—some of the most intriguing and beautiful ones—have come up in science. And we owe it to people to try to explain it. I think there’s that ‘aha’ experience that’s almost sort of orgasmic. If this really is the pinnacle of human creative thought, then we owe it to people—just like we do in art and literature—to expose them to the very best about what it means to be human.
The main point of the book is trying to explain why indeed there is something—why there is matter—rather than nothing. If you were to explain that to a layperson in the most basic way possible, what would you say?
If you ask people what ‘nothing’ is, a lot of people might say, for example, ‘well, just emptiness, empty space.’ But we now realize that that kind of nothing—namely, empty space—not only creates something every second, but that kind of ‘nothing’ is unstable. Quantum mechanics says that out of empty space, because of quantum mechanical fluctuations, things appear all the time. If you wait long enough, something will always arise from that kind of nothing.
Now when I say that, then people say, ‘well, but that’s not really nothing, because space is already there.’ But if you apply the laws of quantum mechanics to space itself, the ideas of quantum gravity—which we have to do if we apply quantum mechanics to general relativity—then even space itself can arise from nothing. There can literally be no space, and suddenly a universe can pop into existence. That, again, is required—it’ll happen all the time.
And then people say, that’s not nothing, because the laws for physics were there. But I point out that our theories have driven us to the notion that our universe is not unique, that there may be many universes with different laws of physics, and we can understand that even the laws themselves may arise spontaneously. There may be different laws in each universe, and we may find ourselves in this universe simply because the laws of physics allow us to exist.
I don’t think this makes the universe any less mysterious, or awesome, or inspiring. In fact, in some sense, it makes it more inspiring to imagine the remarkable set of circumstances and properties that led to our existence here today. Knowing how it actually happened is like what Richard Dawkins used to say about a rainbow: knowing how a rainbow works doesn’t make it any less beautiful.
You’re widely identified as a public intellectual, and have been involved in the debate over teaching intelligent design in schools. What motivates you to take on this role?
Science is the basis of our modern world. And if you want to make sensible decisions, especially policy decisions—about not only education but about the world—they should be based in reality. I don’t want everyone to become a physics expert, but I want people to have enough perspective to know the difference between sense and nonsense.
That aside, I get angry when people are lying to the public, and I usually write when I get angry. And I’m particularly interested in education—I think we owe it to our children to give them the best science education they can get, especially if they want to be competitive in the 21st century. The countries that will be competitive, economically, are the ones who have an educated workforce that’s capable of dealing with the scientific and technological advances that are going to drive the 21st century.
And I get really upset when I see people not only not trying to educate students better, but in fact trying to do the exact opposite. We don’t educate them well enough about biology or physics, for example, and for people to try knowingly to keep our students ignorant, it made me very upset, and I felt it was very important for me to enter the discussion.
This past year’s big news in physics came out of the Large Hadron Collider in Europe, where some evidence has suggested the existence of the long-sought Higgs Boson particle. What is exciting about this?
For New Scientist I wrote a piece explaining the Higgs Boson, what’s it all about, what makes it exciting, and what the good and bad is. It really means something remarkable—it means that our mass, and the mass of everything we see, the reason we exist—is all an accident. It says that empty space is endowed with these weird properties, so when particles travel through it, they interact with this field that permeates space. It’s like walking through molasses. Some particles interact with it more strongly, and they act like they’re more massive, and other particles interact with it less strongly. They can move through it more easily and can act like they’re less massive. But at a fundamental level, without that molasses, it’d all be massless. So it says that basically, our entire perception of the universe in which we live—indeed our own existence—is an accident of circumstances of the existence of this field permeating empty space.
If it’s really true, it’s an amazing vindication of 40 years of the most remarkable theoretical edifice that was built to describe nature. It would be remarkable if it were true, because most often, nature surprises us, and proves us wrong. In some sense, I was kind of hoping the Higgs wouldn’t be discovered at CERN, because if you’re a theoretical physicist, the two most exciting states to be in are wrong and confused.
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