Sunday, September 18, 2011

Physics is Good for Your Brane

As I continue my reading of Greene, I find myself enjoying the precision with which he uses language.   That precision makes him really quite accessible, but it has another collateral benefit.   The way in which he articulates the dynamics of quantum theory, general relativity, and the bridge theories that attempt to unify them lights them up in ways I've not had them lit up for me before.

In particular, the way he expresses string theory has allowed me, for the first time, to get a feel for why that theory is so compelling.  It's always seemed a bit on the precious side before, an odd amalgam of awkward imagery and mathematical abstraction.

But as Greene expresses it, the dimensionality of strings has popped.  Strings are...objects/energies that exist in one dimension.  Branes, which are the membranes within m-theory, can be zero-branes (singularities), one-branes (strings), two-branes (membranes), three-branes (three-dimensional), and on up through the ten-dimensions that comprise being.

Yeah, I know, I'm not totally capturing it.  But as Greene describes it in detail in the two chapters dealing with both string theory and it's more robust offspring M-Theory, it presents a compelling story of the foundation of things.

In fact, it's a more elegant vision of the underlying structure of our universe than atomic theory.  Those periodic table elements are just too cluttery...and, in fact, if you go back to what "atom" was originally supposed to mean when Democritus came up with the word, the "atoms" in the periodic table are not "atoms" at all.

If atom means "it can't be divided," then something you can split just ain't it.   But branes?  Those might well be.  M-Theory feels intuitively right.

Another fascinating tidbit in Greene comes when he explores the Many Worlds concept, which is how he terms the concept of the multiverse.  Working off of the writings of physicist David Deutsch, Greene notes that just as M-Theory resolves the tension between quantum theory and general relativity, it also seems to potentially resolve the tension between proponents of free will and proponents of determinism.

As Greene understands it, the idea of a functionally infinite array of multiverses means that free will finally has a place in the structures of spacetime.  Reality at the quantum level simply does not resemble a series of little gears and cogs, but is far more dynamic, energetic and generative.  While retaining a multiverse that is solid-state in it's completeness, this renders a radically mechanistic determinism meaningless.

This meshes with my intuition.  Unlike Greene, though, I see this through the theological lenses of free will and predestination.  If God's creation is what M-Theory describes, there's suddenly plenty of room for Pelagius and Augustine to sit down with a beer on a nice fall afternoon and just chill.

Which, I think, might just be a good thing.