Thursday, August 25, 2005

Freedom and Uncertainty

We were having a discussion last night at dinner about freedom and uncertainty in the universe. I was reflecting on what the Heisenberg Uncertainty Principle (HUP) implies about the universe as created by God.

For those unfamiliar with Heisenberg’s theory, it’s this:
The more precisely the position [of a particle, e.g. electron] is determined, the less precisely the momentum is known in this instant, and vice versa.”

In other words, you cannot know both a particle’s position and its movement at the same time. In the quantum world, you must speak in probabilities. For example, as this website helpfully explains:
I can only say that an atom will be at some location with a 99 % probability, and that there will be a 1 % probability it will be somewhere else (in fact, there will be a small but finite probability that it can even be found across the Universe).

Heisenberg was primarily concerned with measurement. His principle implied that previously certain Classical ‘realities’, such as speed, direction, mass, position, were meaningless in the new quantum world and he argued that some aspects come into existence only as they are measured. ("The 'path' comes into existence only when we observe it.") In this way, the uncertainty at the heart of the quantum world is not a result of our poor measurement technique, but an integral part of the universe itself.

This had massive implications, not least for Newton’s idea of causality. In simple terms, the classical view was that if the position and momentum of every particle in the universe could be determined, then you could predict the path of each based on the forces acting on it, i.e. predict the future. Of course, to Newton, only God could possibly have the observational and computational power to accomplish this. But, as Heisenberg pointed out: "In the sharp formulation of the law of causality—‘if we know the present exactly, we can calculate the future’-it is not the conclusion that is wrong but the premise." Essentially, what he’s saying is that it’s impossible to know the present exactly (but the limit is not on the knowing, but on the ‘exactly’).

The question I asked is, since the uncertainty principle seems to be part of the very fabric of the universe and an integral characteristic of quantum particles, is the universe ‘uncertain’ even to God? In the same way as He’s given us freedom, has He built a similar freedom into the physical universe?

Dad is reading Greg Boyd’s ‘Satan and the Problem of Evil’ and was similarly reflecting on what it meant for humans (and angels) to have real freedom, and the necessary uncertainty built into that.

Thoughts anyone?

(Quotes are taken from this website where you can also read more about Heisenberg)

3 comments:

Matt said...

A fascinating topic. Will have to have a discussion when you're back in DH1. See if we can get some non-physicists on board too.

Just a quick thought: does the uncertainty in the world give a natural explanation of the supernatural?

cfg said...

A note to the non-physicists... this is not a 'new' theory. Heisenberg's remarks here are from 1927!

Anonymous said...

Even some of us lowly non-physicists have heard of Heisenberg :P ;)

Greg Boyd was at Revive again this year, and was utterly excellent. We shall indeed have to have a summit on Openness (that's what the theologians call it) at some point ...although, do we have any hardline determinsts in our midst to make things interesting?