I watched a debate this week between journalist Robert Wright and physicist Lawrence Krauss on “the origins of the universe, quantum weirdness and the limits of scientific knowledge,” as an announcement from Union Theological Seminary, which hosted the event, put it.
Although the event featured lots of witty banter, it ended up being more frustrating than fun. Wright (an old friend, with whom I have sparred on his internet show Bloggingheads.tv) asked Krauss to clarify his positions on religion, philosophy and science, and Krauss kept demanding that Wright define his terms. What does he mean by “New Atheism”? “Scientism”? “Proselytize”? “Imponderable”?
Krauss’s obfuscations intensified when Wright raised—or tried to raise--objections to Krauss’s 2012 book A Universe From Nothing: Why There Is Something Rather Than Nothing. When Wright sought to summarize the book’s thesis, Krauss interrupted him once again, saying, “You’re making it much more complicated than it has to be.”
Krauss then launched into an extremely complicated, rambling disquisition on the meaning of “nothing.” Wright, exasperated, blurted out, “People are going to leave tonight without knowing what the criticism of your book is if you continue to filibuster!”
Since Krauss can’t interrupt me, let me spell out some objections to his book. I’ll start with mine. Here’s what I said about Krauss’s book three years ago:
Decades ago, physicists such as the legendary John Wheeler proposed that, according to the probabilistic dictates of quantum field theory, even an apparently perfect vacuum seethes with particles and antiparticles popping into and out of existence. In 1990, the Russian physicist Andrei Linde assured me that our entire cosmos—as well as an infinite number of other universes—might have sprung from a primordial "quantum fluctuation."
I took this notion—and I think Linde presented it—as a bit of mind-titillating whimsy. But Krauss asks us to take the quantum theory of creation seriously, and so does evolutionary biologist Richard Dawkins. "Even the last remaining trump card of the theologian, 'Why is there something rather than nothing?,' shrivels up before your eyes as you read these pages," Dawkins writes in an afterword to Krauss's book. "If On the Origin of Species was biology's deadliest blow to supernaturalism, we may come to see A Universe From Nothing as the equivalent from cosmology."
Whaaaa…??!! Dawkins is comparing the most enduringly profound scientific treatise in history to a pop-science book that recycles a bunch of stale ideas from physics and cosmology. This absurd hyperbole says less about the merits of Krauss's derivative book than it does about the judgment-impairing intensity of Dawkins's hatred of religion.
Krauss and I then had an exchange in the comments section of my blog [see Postscript below]. But what do I know? Like Robert Wright, I’m just a journalist. So let’s see what David Albert of Columbia said about Krauss’s book in The New York Times.
“It happens that ever since the scientific revolution of the 17th century, what physics has given us in the way of candidates for the fundamental laws of nature have as a general rule simply taken it for granted that there is, at the bottom of everything, some basic, elementary, eternally persisting, concrete, physical stuff. Newton, for example, took that elementary stuff to consist of material particles. And physicists at the end of the 19th century took that elementary stuff to consist of both material particles and electromagnetic fields. And so on. And what the fundamental laws of nature are about, and all the fundamental laws of nature are about, and all there is for the fundamental laws of nature to be about, insofar as physics has ever been able to imagine, is how that elementary stuff is arranged. The fundamental laws of nature generally take the form of rules concerning which arrangements of that stuff are physically possible and which aren’t, or rules connecting the arrangements of that elementary stuff at later times to its arrangement at earlier times, or something like that. But the laws have no bearing whatsoever on questions of where the elementary stuff came from, or of why the world should have consisted of the particular elementary stuff it does, as opposed to something else, or to nothing at all.
The fundamental physical laws that Krauss is talking about in A Universe From Nothing--the laws of relativistic quantum field theories--are no exception to this. The particular, eternally persisting, elementary physical stuff of the world, according to the standard presentations of relativistic quantum field theories, consists (unsurprisingly) of relativistic quantum fields. And the fundamental laws of this theory take the form of rules concerning which arrangements of those fields are physically possible and which aren’t, and rules connecting the arrangements of those fields at later times to their arrangements at earlier times, and so on--and they have nothing whatsoever to say on the subject of where those fields came from, or of why the world should have consisted of the particular kinds of fields it does, or of why it should have consisted of fields at all, or of why there should have been a world in the first place. Period. Case closed. End of story.
When Wright mentioned Albert’s review, Krauss dismissed Albert as a philosopher, who was probably upset by Krauss’s jibes about philosophy. Albert is indeed a professor of philosophy, but he has a doctorate in physics.
Krauss told me after his conversation with Wright that no real physicist has voiced objections to his book. That brings me to South African physicist George Ellis. When I interviewed Ellis last year, I asked him if Krauss’s book answers the question posed by its subtitle. Ellis responded:
Certainly not. He is presenting untested speculative theories of how things came into existence out of a pre-existing complex of entities, including variational principles, quantum field theory, specific symmetry groups, a bubbling vacuum, all the components of the standard model of particle physics, and so on. He does not explain in what way these entities could have pre-existed the coming into being of the universe, why they should have existed at all, or why they should have had the form they did. And he gives no experimental or observational process whereby we could test these vivid speculations of the supposed universe-generation mechanism. How indeed can you test what existed before the universe existed? You can’t.
Thus what he is presenting is not tested science. It’s a philosophical speculation, which he apparently believes is so compelling he does not have to give any specification of evidence that would confirm it is true. Well, you can’t get any evidence about what existed before space and time came into being. Above all he believes that these mathematically based speculations solve thousand year old philosophical conundrums, without seriously engaging those philosophical issues. The belief that all of reality can be fully comprehended in terms of physics and the equations of physics is a fantasy. As pointed out so well by Eddington in his Gifford lectures, they are partial and incomplete representations of physical, biological, psychological, and social reality.
And above all Krauss does not address why the laws of physics exist, why they have the form they have, or in what kind of manifestation they existed before the universe existed (which he must believe if he believes they brought the universe into existence). Who or what dreamt up symmetry principles, Lagrangians, specific symmetry groups, gauge theories, and so on? He does not begin to answer these questions. It’s very ironic when he says philosophy is bunk and then himself engages in this kind of attempt at philosophy.
When I mentioned Ellis’s critique to Krauss, he claimed that Ellis, although once a physicist, is now a “theologian.” Ellis, a Quaker, has indeed written about religion, among other topics, but he is renowned for his work as a physicist. He co-wrote with Stephen Hawking the classic work The Large-Scale Structure of Spacetime, published in 1973. Just in the past five years, Ellis, now 76, has edited one book on quantum gravity and co-written another on cosmology and has co-written more than a dozen papers on physics, according to his website.
If Ellis isn’t a physicist, Krauss certainly isn’t. So what is he? Ellis describes A Universe From Nothing as a “kind of attempt at philosophy.” The hand-waving sophistry and terminological quibbling that Krauss displayed during his conversation with Wright were also reminiscent of philosophy at its worst. Krauss, perhaps, is just a bad philosopher.
Postscript: After I posted my critique of Krauss’s book in 2012, we had an exchange in the comments sections. Here it is, slightly edited for clarity:
Krauss: I must say that this kind of silly piece from an author who also "went out on a limb" 20 years ago to say physics was over is rather telling... it is just about as cogent.. and demonstrates more an unwillingness to seriously consider the ideas I and others have raised than a desire to create some interest in his blog.
Horgan: Larry, I'll always be grateful to you for helping bring me up to speed on modern cosmology 22 years ago when I was researching an article for Scientific American. And what's disappointing is that, apart from the discovery of the acceleration of the cosmic expansion, which was certainly a big surprise, nothing has really changed since then. You and/or your popularizing colleagues--Hawking, Greene, Kaku, Susskind--are still marketing various unsubstantiated versions of inflation, multiverse theories, string theory, vacuum energy, anthropic principle, etc. What's ironic is that, although you don't have any more evidence for these speculations, your marketing of them has become more aggressive... and yet you accuse ME of hype.
Krauss: John… first, I didn't make any definitive claims.. and I get offended when people claim I make such.. second I tried to indicate how much has changed in the last 22 years.. that is the purpose of the book.. things are dramatically different than they were then, and I went through a very careful analysis to describe these changes..... the analysis of fluctuations in the CMB, the discovery that the universe is flat.. these are REAL empirical discoveries that both impact upon and add credence to many of our ideas.
Horgan: Larry, so you're saying that you're not claiming to have answered the question posed by your book's title? You're just tossing some ideas around, and you don't expect anyone to take them too seriously? OK, that's a useful clarification. It also means that things have not progressed in the last 22 years, in spite of what you just asserted. I think you better tell Dawkins, before he embarrasses himself further.
Krauss did not respond.
Post-Postscript: In a comment below, Krauss suggests that I misunderstand him. Actually, I and other critics understand him all too well.