In January, Lawrence Krauss [pictured], a theoretical physicist and Director of the Origins Institute at Arizona State University, published A Universe From Nothing: Why There Is Something Rather Than Nothing, a book that, as its title suggests, purports to explain how something—and not just any something, but the entire universe—could have emerged from nothing, the kind of nothing implicated by quantum field theory. But before attempting to do so, the book first tells the story of modern cosmology, whipping its way through the big bang to microwave background radiation and the discovery of dark energy. It’s a story that Krauss is well positioned to tell; in recent years he has emerged as an unusually gifted explainer of astrophysics. One of his lectures has been viewed over a million times on YouTube and his cultural reach extends to some unlikely places—last year Miley Cyrus came under fire when she tweeted a quote from Krauss that some Christians found offensive. Krauss’ book quickly became a bestseller, drawing raves from popular atheists like Sam Harris and Richard Dawkins, the latter of which even compared it to The Origin of Species for the way its final chapters were supposed to finally upend "last trump card of the theologian."
I haven’t read the book, but I have added it to my ‘when I get some time’ list. There is a good interview by Andersen with Krause in this article. I like Krause’s answers in that they seem honest. That doesn’t mean I agree. Here is a snippet:
Moving on to your book "A Universe From Nothing," what did you hope to accomplish when you set out to write it?
Krauss: Every time I write a book, I try and think of a hook. People are interested in science, but they don’t always know they’re interested in science, and so I try to find a way to get them interested. Teaching and writing, to me, is really just seduction; you go to where people are and you find something that they’re interested in and you try and use that to convince them that they should be interested in what you have to say.
The religious question "why is there something rather than nothing," has been around since people have been around, and now we’re actually reaching a point where science is beginning to address that question. And so I figured I could use that question as a way to celebrate the revolutionary changes that we’ve achieved in refining our picture of the universe. I didn’t write the book to attack religion, per se. The purpose of the book is to point out all of these amazing things that we now know about the universe. Reading some of the reactions to the book, it seems like you automatically become strident the minute you try to explain something naturally.
Richard Dawkins wrote the afterword for the book—and I thought it was pretentious at the time, but I just decided to go with it—where he compares the book to The Origin of Species. And of course as a scientific work it doesn’t some close to The Origin of Species, which is one of the greatest scientific works ever produced. And I say that as a physicist; I’ve often argued that Darwin was a greater scientist than Einstein. But there is one similarity between my book and Darwin’s—before Darwin life was a miracle; every aspect of life was a miracle, every species was designed, etc. And then what Darwin showed was that simple laws could, in principle, plausibly explain the incredible diversity of life. And while we don’t yet know the ultimate origin of life, for most people it’s plausible that at some point chemistry became biology. What’s amazing to me is that we’re now at a point where we can plausibly argue that a universe full of stuff came from a very simple beginning, the simplest of all beginnings: nothing. That’s been driven by profound revolutions in our understanding of the universe, and that seemed to me to be something worth celebrating, and so what I wanted to do was use this question to get people to face this remarkable universe that we live in.
Your book argues that physics has definitively demonstrated how something can come from nothing. Do you mean that physics has explained how particles can emerge from so-called empty space, or are you making a deeper claim?
Krauss: I’m making a deeper claim, but at the same time I think you’re overstating what I argued. I don’t think I argued that physics has definitively shown how something could come from nothing; physics has shown how plausible physical mechanisms might cause this to happen. I try to be intellectually honest in everything that I write, especially about what we know and what we don’t know. If you’re writing for the public, the one thing you can’t do is overstate your claim, because people are going to believe you. They see I’m a physicist and so if I say that protons are little pink elephants, people might believe me. And so I try to be very careful and responsible. We don’t know how something can come from nothing, but we do know some plausible ways that it might.
But I am certainly claiming a lot more than just that. That it’s possible to create particles from no particles is remarkable—that you can do that with impunity, without violating the conservation of energy and all that, is a remarkable thing. The fact that "nothing," namely empty space, is unstable is amazing. But I’ll be the first to say that empty space as I’m describing it isn’t necessarily nothing, although I will add that it was plenty good enough for Augustine and the people who wrote the Bible. For them an eternal empty void was the definition of nothing, and certainly I show that that kind of nothing ain’t nothing anymore.
But debating physics with Augustine might not be an interesting thing to do in 2012.
Krauss: It might be more interesting than debating some of the moronic philosophers that have written about my book. Given what we know about quantum gravity, or what we presume about quantum gravity, we know you can create space from where there was no space. And so you’ve got a situation where there were no particles in space, but also there was no space. That’s a lot closer to "nothing."
But of course then people say that’s not "nothing," because you can create something from it. They ask, justifiably, where the laws come from. And the last part of the book argues that we’ve been driven to this notion—a notion that I don’t like—that the laws of physics themselves could be an environmental accident. On that theory, physics itself becomes an environmental science, and the laws of physics come into being when the universe comes into being. And to me that’s the last nail in the coffin for "nothingness."
It sounds like you’re arguing that ‘nothing’ is really a quantum vacuum, and that a quantum vacuum is unstable in such a way as to make the production of matter and space inevitable. But a quantum vacuum has properties. For one, it is subject to the equations of quantum field theory. Why should we think of it as nothing?
Krauss: That would be a legitimate argument if that were all I was arguing. By the way it’s a nebulous term to say that something is a quantum vacuum in this way. That’s another term that these theologians and philosophers have started using because they don’t know what the hell it is, but it makes them sound like they know what they’re talking about. When I talk about empty space, I am talking about a quantum vacuum, but when I’m talking about no space whatsoever, I don’t see how you can call it a quantum vacuum. It’s true that I’m applying the laws of quantum mechanics to it, but I’m applying it to nothing, to literally nothing. No space, no time, nothing. There may have been meta-laws that created it, but how you can call that universe that didn’t exist "something" is beyond me. When you go to the level of creating space, you have to argue that if there was no space and no time, there wasn’t any pre-existing quantum vacuum. That’s a later stage.
Even if you accept this argument that nothing is not nothing, you have to acknowledge that nothing is being used in a philosophical sense. But I don’t really give a damn about what "nothing" means to philosophers; I care about the "nothing" of reality. And if the "nothing" of reality is full of stuff, then I’ll go with that.
But I don’t have to accept that argument, because space didn’t exist in the state I’m talking about, and of course then you’ll say that the laws of quantum mechanics existed, and that those are something. But I don’t know what laws existed then. In fact, most of the laws of nature didn’t exist before the universe was created; they were created along with the universe, at least in the multiverse picture. The forces of nature, the definition of particles—all these things come into existence with the universe, and in a different universe, different forces and different particles might exist. We don’t yet have the mathematics to describe a multiverse, and so I don’t know what laws are fixed. I also don’t have a quantum theory of gravity, so I can’t tell you for certain how space comes into existence, but to make the argument that a quantum vacuum that has particles is the same as one that doesn’t have particles is to not understand field theory.