Monday, March 26, 2012

Ex nihilo ... something something

Lawrence Krauss has recently published A Universe from Nothing: Why There Is Something Rather Than Nothing wherein he seeks to explain the origin of the universe in purely physicalist, specifically quantum physicalist, terms. Bill Vallicella has berated Krauss for his nonsensical metaphysical musings wrapped up in the garb of scence before and will soon begin reading Universe from Nothing (he will check it out from a library, not wanting to grant it the dignity of actually purchasing it). But he also points to this interesting critique in the New York Times of Krauss's book from which I quote liberally:

What on earth, then, can Krauss have been thinking? Well, there is, as it happens, an interesting difference between relativistic quantum field theories and every previous serious candidate for a fundamental physical theory of the world. Every previous such theory counted material particles among the concrete, fundamental, eternally persisting elementary physical stuff of the world — and relativistic quantum field theories, interestingly and emphatically and unprecedentedly, do not. According to relativistic quantum field theories, particles are to be understood, rather, as specific arrangements of the fields. Certain ­arrangements of the fields, for instance, correspond to there being 14 particles in the universe, and certain other arrangements correspond to there being 276 particles, and certain other arrangements correspond to there being an infinite number of particles, and certain other arrangements correspond to there being no particles at all. And those last arrangements are referred to, in the jargon of quantum field theories, for obvious reasons, as “vacuum” states. Krauss seems to be thinking that these vacuum states amount to the relativistic-­quantum-field-theoretical version of there not being any physical stuff at all. And he has an argument — or thinks he does — that the laws of relativistic quantum field theories entail that vacuum states are unstable. And that, in a nutshell, is the account he proposes of why there should be something rather than nothing.

But that’s just not right. Relativistic-quantum-field-theoretical vacuum states — no less than giraffes or refrigerators or solar systems — are particular arrangements of elementary physical stuff. The true relativistic-quantum-field-­theoretical equivalent to there not being any physical stuff at all isn’t this or that particular arrangement of the fields — what it is (obviously, and ineluctably, and on the contrary) is the simple absence of the fields! The fact that some arrangements of fields happen to correspond to the existence of particles and some don’t is not a whit more mysterious than the fact that some of the possible arrangements of my fingers happen to correspond to the existence of a fist and some don’t. And the fact that particles can pop in and out of existence, over time, as those fields rearrange themselves, is not a whit more mysterious than the fact that fists can pop in and out of existence, over time, as my fingers rearrange themselves. And none of these poppings — if you look at them aright — amount to anything even remotely in the neighborhood of a creation from nothing.

Krauss, mind you, has heard this kind of talk before, and it makes him crazy. A century ago, it seems to him, nobody would have made so much as a peep about referring to a stretch of space without any material particles in it as “nothing.” And now that he and his colleagues think they have a way of showing how everything there is could imaginably have emerged from a stretch of space like that, the nut cases are moving the goal posts. He complains that “some philosophers and many theologians define and redefine ‘nothing’ as not being any of the versions of nothing that scientists currently describe,” and that “now, I am told by religious critics that I cannot refer to empty space as ‘nothing,’ but rather as a ‘quantum vacuum,’ to distinguish it from the philosopher’s or theologian’s idealized ‘nothing,’ ” and he does a good deal of railing about “the intellectual bankruptcy of much of theology and some of modern philosophy.” But all there is to say about this, as far as I can see, is that Krauss is dead wrong and his religious and philosophical critics are absolutely right. Who cares what we would or would not have made a peep about a hundred years ago? We were wrong a hundred years ago. We know more now. And if what we formerly took for nothing turns out, on closer examination, to have the makings of protons and neutrons and tables and chairs and planets and solar systems and galaxies and universes in it, then it wasn’t nothing, and it couldn’t have been nothing, in the first place. And the history of science — if we understand it correctly — gives us no hint of how it might be possible to imagine otherwise.

Perhaps my ignorance of quantum physics allows me to feel greater awe at the mystery of particles popping into existence than the reviewer's fist when he rearranges his fingers, but I still get the point. I have often heard that physicists have five different definitions of "nothing". Krauss, if his critic is right, seems to be saying that we can have creation from nothing in one (trivial) sense, and if we insist on asking if we can have creation from nothing in a stronger (untrivial) sense, well just shut up.

Discuss this post at the Quodlibeta Forum

6 comments:

TheOFloinn said...

Krauss is also wrong about the "nothing" being recently redefined. That the nothing is the utter absence of something was the original definition.

Alexander Johannesen said...

May I suggest you guys read the book? Krauss goes through a number of different Nothings, from old and obviously wrong ones to new and redefined ones. Krauss is not "also wrong", and even a casual read of his book would clarify that.

Jim S. said...

Well that's justified. I tried to qualify my comments with the phrase "if [Krauss'] critic is right" but of course I'm sniping without having read the book and that's not really playing fair.

Bjørn Are said...

Alexander:

Where does Krauss do that? I have read the book and can't remember there being much about "different nothings" (as if the can be more than one) anywhere, except from some highly inadequate paragraphs on two pages or so in the preface, where he shows little or no understanding of the debate.

He seems to think that nothing is about ... physics ("empty space", "absence of space and time", a state where "laws arose spontaneously"...)?

Have I missed something or do you find his musings here adequate?

Anonymous said...

Bjorn,

Alexander may mean, similar to the review's posting, that Krauss has pointed out past thoughts on space and vacuum, and how later on problems with those concepts were discovered.

But yes, Krauss basically wrote a book that does little more than show he has absolutely no idea what he's talking about regarding 'something out of nothing' as philosophically argued.

Bjørn Are said...

Thx, my point was about TOF's comment on the "nothing" being recently redefined, which as he says is absolutely nonsense - if we are talking philosophy and the kind of theistic arguments that Krauss and Dawkins believe the book are answering - and that the book is marketed as adressing.

This brought the reply from Alexander that "Krauss goes through a number of different Nothings, from old and obviously wrong ones to new and redefined ones. Krauss is not "also wrong", and even a casual read of his book would clarify that".

My reading of the book has clarified that Krauss believes nothing is something (or, rather that to do physics on "nothing" it must be something), and even says so - something which indicates he understands little of cosmological arguments.

He even seems to think that "Who created the creator" is a meaningfull question, and insists that "An infinite regress of some creative force that begets itself, even some imagined force that is greater than turtles, doesn’t get us any closer to what it is that gives rise to the universe. Nonetheless, this metaphor of an infinite regression may actually be closer to the real process by which the universe came to be than a single creator would explain."

Believing that God has begotten himself is so beyond logic, Christian theology and natural philosophy that I wonder who proofreads such books.