Tuesday, March 27, 2012

Something from Nothing

Lawrence Krauss is a well-known cosmologist and popular-science writer who apparently wishes to be numbered among the ranks of those who write science in order to disprove the existence of God. Krauss has a new book out in which he aspires to demonstrate that the universe could have arisen out of nothing, or almost nothing, and that a Creator isn't necessary to explain cosmogeny. The book is titled A Universe from Nothing: Why There Is Something Rather Than Nothing and it received a rather derisory review in the New York Times from Columbia philosopher of science David Albert, author of Quantum Mechanics and Experience.

Krauss argues that the laws of quantum mechanics working in the quantum vacuum (Krauss' "nothing") could have produced a "fluctuation" that produced the universe. In this view, which is not particularly new, the universe is seen as the debris from an inopportune quantum belch, as it were. Albert, not to put too fine a point on it, thinks this is rather ridiculous:
Where, for starters, are the laws of quantum mechanics themselves supposed to have come from? Krauss is more or less upfront, as it turns out, about not having a clue about that. He acknowledges (albeit in a parenthesis, and just a few pages before the end of the book) that every­thing he has been talking about simply takes the basic principles of quantum mechanics for granted.
So, there must have been something, the laws of quantum mechanics, which produced the universe, but where did these laws come from? Were they just floating about in .... in what? It couldn't have been space because space and time didn't exist before there was a universe so where exactly were the laws which generated the cosmos. The most likely candidate, the mind of God, is exactly what Krauss is trying to show didn't exist, so that's not a plausible option for him.

Albert explores for several paragraphs the cul de sac Krauss has constructed for himself. The problem is that what Krauss is calling "nothing" isn't really nothing. To argue that the universe's origin out of the quantum vacuum is an origin ex nihilo is like arguing that a fist popping into existence where no fist was before is the creation of a fist out of nothing:
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.
There's more to Albert's review of Krauss at the link. Put simply, Krauss wants to say that the universe could have come from nothing, but what he calls "nothing" is really not nothing in the sense that most people construe the word. And if that's true, if Krauss' "nothing" is really a vast congeries of forces, fields, and elementary particles with the inherent potential to burst into a space-time, mass-energy universe then where did all that "nothingness" come from?