Fleming: Why is there something rather than nothing? The philosopher Martin Heidegger called this the fundamental question in all of metaphysics. For scientists, the question might be put this way: how can our universe pop out of nothing, nearly 14 billion years ago? Empty space one moment, then a second later, an exploding swirl of energy. Believe it or not, some scientists think we may finally have an answer, though a new book by Lawrence Krauss has sparked an intellectual brawl. Steve Paulson talked with Krauss and fellow physicist Marcelo Gleiser to find out what this modern creation story means for both science and religion.
Paulson: This is a story about nothing and the beginning of everything and how nothing can become something. It' s also a story about why some scientists think philosophers are useless, while others say certain scientists themselves have become arrogant and full of hubris. But before we go any further, we need to consider a basic question, what is nothing?
Lawrence Krauss: To a physicist, the first version of nothing of is simply empty space with nothing in it. You wouldn' t have any particles, all the radiation and so, there's literally nothing in it. But that nothing is actually quite complicated because of quantum mechanics and relativity. It turns out empty space is a boiling, bubbling brew of virtual particles, popping in and out of existence in a time so short that you can' t even measure them.
Paulson: That' s Lawrence Krauss, a theoretical physicist and director of the Origins Institute at Arizona State University. His idea of nothing is quite different from what you' d hear from a theologian or philosopher, who is more likely to talk about non-existence or non-being.
Krauss: That' s true but I don' t exactly know that those words mean. It seems to me that nothing is a physical quantity just like something is and we need to look to the universe to ask what it is. Now, from a physical point of view, one can get a little closer to that vague and I would say ill-defined notion of non-being that philosophers and theologians might have argued about for thousands of years by saying, well, in fact there are other versions of nothing and in fact, you can imagine no space and no time, which of course I think is a better version of non-being and non-existence. But if we apply the laws of quantum mechanics to gravity, then in that theory, even space itself can pop into existence, spontaneously - space and time, where there were no time and space before. And, boy, that' s pretty close to what I think anyone would argue is nothing but, you know, if it doesn' t satisfy those who think that that' s non-being, so be it. But I' m much more interested in the nothing of the actual universe than some vague, a priori definition of what non-being is.
Paulson: Lawrence Krauss has written a provocative book called “A Universe from Nothing.” It' s an argument for how science can finally answer the age-old mystery of why there is something rather than nothing. Now, Krauss is quick to say he doesn' t have definitive proof; he' s offering a plausible explanation based on the latest science. Which left me with a basic question: Can you explain to a non-physicist how the universe can be created out of nothing?
Krauss: Yeah, given what we understand about quantum gravity, about quantum mechanics and general relativity together, it is quite possible that literally a small space could pop into existence where there was none before. Normally such spaces will pop in and out of existence in a timescale so short you can' t measure them and those universes will disappear quite quickly. But what is also remarkable is we have great evidence that in our universe, in very early times, and by very early I mean something like a millionth of a billionth of a billionth of a billionth of a second after the Big Bang, our universe puffed up by a huge amount, energy got trapped in space and that energy caused the universe to expand incredibly rapidly. We call that a period of inflation, and it sounds like a scam: how can you get something from nothing? How can you get a free lunch? Well, it turns out, physics allows you to get a free lunch.
Paulson: I guess, what' s so bizarre, for the outsider, for the non-physicist is...
Krauss: It' s bizarre for me too.
Paulson: But it sounds like you' re saying, it' s no big deal in the world of quantum physics for something to come out of nothing. For some reason, that' s not a problem and for the outsider it seems like a huge problem.
Krauss: In fact, it' s not only not a big problem, it would be the much more remarkable if the question would be, why is there nothing rather than something? Except we wouldn' t be around to ask the question. Because nothing is essentially unstable, empty space due to the laws of quantum mechanics of gravity is unstable, if you leave it long enough it will always create particles. So the real point is that distinction, that common sense distinction between something and nothing in common parlance is not such a distinction in physics. It' s due to the weird laws of quantum mechanics. And the really interesting questionsin our universe is how did it evolve and how did we get here? And this why the question which made everything seem so profound has been replaced and it often happens in science, I think, that questions that seem to have a certain type of significance, the meaning of those words, changes. I mean, it' s not a scam and it' s not something we do to defeat philosophers, we do it because we take our definitions from the universe.
Paulson: I have to follow up on that because there is that common saying that theology and philosophy deal with the “why” questions, while science deals with the “how” questions - because the fundamental religious question, of course, is why are we here? Are you saying those “why” questions should not even be asked?
Krauss: Well, I think most of the “why” questions are really “how” questions because if you ask “why” what you really mean is you' re presuming purpose. You' re making a presumption that there' s some meaning, some purpose and I would argue that if you insist on why, you' re assuming the answer before you ask the question. You' re assuming there is purpose to the universe and that there is some reason that we came to exist. But why should there be a reason and why must there be purpose to the universe? In science, we just try to figure out how it happened, there may be purpose to the universe and science certainly can' t answer that question ultimately in the negative but what we can say is there's no evidence of purpose, that everything we see, as far as we can tell, came into existence by laws of physics that we can understand without any supernatural shenanigans. There doesn' t have to be a reason and that may disappoint some people. But in fact, I find it quite embolding, it energizes me to think that due to a set of accidents, remarkably in this remote corner of the universe, in the middle of nowhere of our galaxy, on a remote planet, that we happen to evolve with a consciousness that can ask these questions and we should enjoy our brief moment in the sun and realize the meaning of our lives is the meanings we make from it.
Paulson: Let me just follow up on that word, “meaning.” Basically you' re saying that, you know, we construct our own meaning and it does raise the question of whether science is in the business of helping us find meaning, because of course, again, that' s traditionally the domain of religion and philosophy.
Krauss: Well, I think that what what the last few thousand years have shown us is that the domain of religion and philosophy is shrinking. In fact I would have argued that the domain of religion shrank to zero a long time ago. So I think what is amazing is because of the astounding and remarkable developments that have taken place in science, we are being pushed to the threshold of asking questions which we may not have thought were scientific questions and initially were the domain of science. But the domain of science is to understand the universe.
Paulson: What' s especially striking about Lawrence Krauss' s book is how he' s linked his theory about the origins of the universe to the new atheist movement. In fact, Richard Dawkins has written the afterword, claiming that Krauss has demolished the theological arguments in cosmology, just as Charles Darwin did in biology. And I will say, Krauss does not mince words when he talks about religious ideas about creation.
Krauss: I don' t write things to attack God because I don' t think God' s important enough to attack, frankly. I think what is amazing is understanding reality. Then this need for belief in myths and superstition will go away. And that' a good thing. The scriptures, the books of the world' s great religions were written by people who didn' t even know the Earth goes around the Sun. How can they know anything about the world that' s sensible?
Paulson: You are not just hard on religion and theology, your book has also sparked a very public spat between physicists and philosophers. And at one point you say some of modern philosophy is intellectually bankrupt. Why are you so hard on philosophers of science?
Krauss: Well, I don' t believe we can make great progress understanding nature or even understanding ourselves by turning inwards. I would go so far as to say we can only really claim to know things that we can apparently test but unless we reflect on reality, then we' re just playing mind games, in my opinion.
Paulson: Ok. I have to ask you about that scathing review of your book in the New York Times Book Review by the philosopher of science, David Albert, who it’s worth pointing out has a Ph.D in physics. And it comes back to this...
Krauss: But he' s not a physicist, he' s a philosopher.
Paulson: Right, it kind of comes back to this discussion of what nothing means and he said, you have not answered the basic problem of something coming out of nothing because you don' t explain where the quantum fields came from in the first place or why the laws of physics are the way they are - for instance, why we have quantum mechanics.
Krauss: Yeah, I think he should have read the book before reviewing it, I think it would have helped that review immensely if he' d actually read more than the preface and the afterword.
Paulson: His point is that you don' t answer the core philosophical question, which is “first cause.”
Krauss: Yeah. Well, in fact I try very carefully to explain what I do and don' t do. What he said is, Lawrence Krauss didn' t write the book I would have liked to have written about some other subject. I actually do describe, exactly, how it's possible that quantum fields can come into existence and if that' s not the question he wanted answered, too bad.
Paulson: I guess the question is, don' t there have to be laws of physics for any of that stuff to happen? And therefore, the something can come out of nothing.
Krauss: Well, you know, it' s a good question. However people are driven to the idea now, that in fact, maybe all laws of physics are possible. Namely, that every different kind of law you could imagine might arise in some universe, it might arise and exist for a microscopic instant or an eternity and it's an interesting question that we may not be able to resolve, as I say. If our universe is one of potentially an infinite number of universes, some of which are popping into existence right now, then we may indeed ask the question, why the multiverse?
Paulson: It seems that we are really talking about a modern creation story here and the question on the table is whether science can finally come up with its own version of a creation story, that once and for all replaces all those religious creation stories out there. And it would seem that there are ultimately two options, either the universe appeared at some point in time, the first of many in the multiverse, let' say, or it has existed forever. Would you agree that those are the two choices?
Krauss: Absolutely. But I think the same is true with religion. I mean, let me point out that science is more than a story and by the way it has replaced the creation myths of religion long ago. It has replaced those creation myths. But I would argue that, you know, the same questions that you can throw at science, is the multiverse eternal and why is it eternal? - God is just an intellectual copout for lazy minds. They basically say, look, that fundamental question of how it came into existence is so difficult, I' m going to assume some incredible intelligence and by the way, I won' t even ask the question, how did that incredible intelligence come into being. I'll just say it had to be around forever because I can't have any other explanation. It seems to me that that is just intellectually lazy.
Paulson: So, getting back to these two choices, this gets very speculative, of course, we don' t really know whether we' re in the multiverse or not, but would you believe that there was one original universe, whether it' s ours or another universe or whether this has just been going on forever?
Krauss: Well, first of all, I don' t like to use the word “believe.” It' s an irrelevant word for science but everything I know about science suggests that, in fact, there probably is an eternal multiverse which our universe is a part of. So, my best guess is, in fact, that the multiverse is eternal but certainly our universe popped into it.
Paulson: Well, there' s another question here as well: is the universe ultimately knowable? Because, it would seem that one very legitimate response for both a scientist and an atheist would be to say, no, there will be some fundamental mysteries beyond the capacity of science to explain.
Krauss: Well, there may be. I mean, I wrote a book about Richard Feynman and Feynman would say, you know, maybe the laws of physics are like an onion, you just keep peeling it back and there are an infinite numbers of layers and you never have a theory of everything. That could be the case. But that makes life even more fascinating, it seems to me, than presuming that you know everything by simply saying that God exists. That' s just boring and tedious.
Paulson: As you might imagine, Lawrence Krauss is catching lots of flak from religious thinkers and philosophers but also from some fellow scientists. For a different take on cosmology and spirituality, I turned to Marcelo Gleiser. A physicist at Dartmouth College who writes for the NPR Science blog, 13.7, Gleiser recently blogged about the flap over Krauss' s book, noting what he calls its “triumphant tone that science will conquer all.” Gleiser himself is far more cautious.
Marcelo Gleiser: We have no answers to three very fundamental questions: the origins of the universe, the origins of life, and the origins of consciousness. Now, it is very possible that we will understand consciousness and life because these are things that in a sense would be in our control. I mean, we can run lab experiments. But the origins of the universe is a really complicated question. It really kind of defies the very core of what science is. And I do not know how we could possibly understand it because even if you made a model and people have made models of quantum mechanics of portions of the universe, you still have all these implicit assumptions in there, which you are using: conservation of energy, you' re using general relativity, you' re using quantum mechanics, so you can always ask, ok, but where do these laws come from? So, you have to go beyond science and create a kind of meta-science, which is explaining why science works the way it does and we don' t have that. And I don' t even know how to come to grips with that. And so maybe, there are questions that are unknowable. And if that' s true, you have to accept that and be humbled by it. And say, look there' s all this wonderful stuff we can explain about the world, but we just don' t need to explain everything.
Paulson: I went to see Marcelo Gleiser at his Dartmouth office, where we talked about his book, “A Tear at the Edge of Creation.” Gleiser believes his field of physics has been seduced by the so-called search for everything, a beautiful theory that would unify all of physics. Elaborate mathematical models have lead many physicists to embrace String Theory and the Multiverse, which so far have no empirical proof.
Gleiser: Even though this is a very compelling idea, the notion that there is this kind of hidden explanation for all that exists in the world and in fact it is an idea that completely seduced me in my own career, but you know, I started to realize that it was becoming extremely convoluted. We' re not getting any closer to this and in fact all the unified ideas in physics are really more approximations than really a final pristine unity. Those unifications we talk about in physics, they are not perfect unifications. They always have a little flaw. And I started to realize that maybe we're pursuing the wrong dream.
Paulson: Gleiser says there' s a curious precedent for the scientists’ obsession with a single explanation for everything. As he was studying the history of science, he came to think that this idea comes straight out of monotheistic religion.
Gleiser: And I think that intellectually, the search for unification of nature is really our rationalization of the notion of God. It' s sort of a way of thinking about God through the tools of science.
Paulson: I' d have to say that highly regarded physicists like Steven Weinberg or Brian Greene would be horrified that there' s anything religious about what they' re trying to do, you know, because they' re big advocates of trying to find a theory of everything. What makes this religious, this search?
Gleiser: Well, you have to take religion here in a very broad sense. I' m not saying that superstring theories are religious theories. I' m an atheist, actually I have to distinguish, I'm an agnostic. I' m not an atheist, so that is not my point at all. What I mean is that this notion that nature is one, and all is one , is a notion that is much older that Galileo and Newton and all these guys. Now, to talk about Einstein, he used to call science the most honest of all religions, in the sense that what motivates a scientist is his cosmic religious theory. What he means is kind of this aura with the mysterious and a way to peer into the darkness is through human reasoning and intuition, this devotion, this sort of idea that you can give your life to understand this mystery is in essence a very religious choice.
Paulson: Well, that raises the question whether you think that the universe is ultimately knowable. Is it knowable? Or are you comfortable saying, it' s not and there will always be mystery there and that' s OK.
Gleiser: That' s exactly right, we can know about our world through science and the way we understand reality is through our measurements and our tools. And even though they are wonderful and they are advancing, they have limits, so you can measure things through a certain precision, you can measure things to a certain distance but beyond that you have darkness, you do not know.
Paulson: But I think the answer of a lot of scientists would be, yes, there are many things we don't understand right now. We don' t understand what matter is, what dark energy is, all kind of things we don' t understand and how the mind works and the connection between brain and mind but science is all about trying to figure out and understand. And to say that we will never be able to understand it is defeatism . Scientific defeatism.
Gleiser: Right and I have heard that before and I have corrected the critics by saying that is not what I mean, what I mean is precisely the opposite. I think that science is an eternal pursuit of knowledge, that there is no end to the quest. So what I' m concerned about is the sort of excess of confidence on the part of certain scientists to say that, yes, there is a final theory of nature and that we can get to it. I think that is incredibly arrogant and it does a disservice to what science really is trying to do, which is to give meaning to our lives, ultimately.
Paulson: Do you think this is a spiritual position, to say that ultimately the universe is unknowable in some final sense, that there will always be a mystery to it?
Gleiser: Yes, I think that is a deeply spiritual position and I think there is nothing wrong with this sort of reconciliation between science and spirituality. In fact, I would even propose a different definition of sacred, because in a sense, what people at least traditionally think of the sacred is a place you are not where you were before, a place where you have to pay attention. So you go to a temple and if you are not a religious person but you are John Muir, he is going to say, this is my temple, this is my sacred spot, and within that notion of the sacred, there' s this very subjective feeling, of awe with the mystery of what you do not know. And to me the main sort of engine behind scientific inspiration is precisely this seduction of the unknown. And so, if we find our sense of what is sacred in the parts of the universe that I do not understand, then the pursuit of science becomes the pursuit of the sacred.
Fleming: Marcelo Gleiser is a physicist at Dartmouth College. Steve Paulson also talked to Arizona State University physicist Lawrence Krauss.