Wednesday, February 18, 2009

Time Travel - Musings on a Stop-Motion Universe

Musings on a Stop-Motion Universe

An episode of the New Twilight Zone (the one that ran on CBS in the eighties) that stands out in my mind is one in which, according to an online episode guide,

A couple awaken one morning to find their home overrun with faceless blue-clad workmen and their neighborhood abandoned.

As I recall, these creepy workmen looked like forerunners of Blue Man Group, but they were far from the point of the story. The episode had to do with getting caught outside of time; it's premise was quite similar to Stephen King's The Langoliers. (Which I've never read, although I did see the made-for-TV-movie.)

These two stories present similar pictures of how time works. In both, we experience time by moving through a sequence of frames. Each frame is world unto itself with a duration of one minute. I don't think either story stated it explicitly, but each frame appeared to be a complete instance of the universe: including everything except for human beings (and presumably animals.) People were not attached to any one frame, but instead moved seamlessly from frame to frame with each passing minute.

Both stories deal with what happens to a minute after its minute is up. In the TZ episode, the blue workmen arrive and basically start "striking the set." They need to make room for more minutes that are coming down the pike. In the Stephen King story, the Pacmanesque Langoliers show up and eat the discarded world. Both stories deal with people who have been left behind in the wrong minute trying to get caught up to the present.

I thought about both of these stories a while back when I started reading Julian Barbour's The End of Time. This book is not science fiction; it's theoretical physics. According to a model developed by Barbour, every possible state of the universe exists—whole and pre-made—in a vast configuration space. For readers who dabble in such topics, Barbour's idea may sound similar to the many-worlds hypothesis of quantum theory, which states that a new universe is created at every instance of quantum branching. But in Barbour's model there is no branching. All possible "branches" are already accounted for in the myriad configurations of the universe. Unlike the one-minute-long universes of the Langoliers and the Twilight Zone, these frames (configurations) are motionless and timeless. We don't "move through" them; we're simply part of them.

Each frame has embedded within it a history of memories, but these memories are not exactly true. They are just a necessary product of a certain quantum snapshot of the universe.

In the configuration space, similar universes are clustered together. What we experience as time and motion and even cause-and-effect is actually a waveform running through these clusters. The waveform creates the illusion of connectivity between configurations that have consistent, sequential memories embedded within them. So our consciousness is just an illusion, which carries with it the illusions of time and motion.

So take a simple action: dropping an egg on the kitchen floor. There is a complete instance of the universe in which the egg sits poised between my fingers in an untenable position. There is another configuration of the universe in which the egg is free of my hand and "on the way down." (In fact, nothing is going anywhere.) There is yet another configuration of the universe in which the egg is just above the floor. Finally, there is an instance of the universe in which egg lies smashed on the floor of the kitchen. Of course, there are bazillions more of these configurations than I've named here even for this simple scenario, but you get the idea. Each universe reflects a random reshuffling of all possible quantum states. That I stated them in the order I did only reflects my own deep attachments to the illusions of motion and cause-and-effect.

I have to admit that I love this model of the universe. It is, if nothing else, a startling and beautiful depiction. The storytelling possibilities around such a model are endless.

But as resonant as we might find Barbour's model in poetic terms (witness the fact that watered-down versions of it appeared in fiction before it was ever introduced as science), this would be a very difficult premise to accept rationally. For one thing, it argues against the reality of our consciousness. Most of us would be hard-pressed to let that reality go, even theoretically. And besides, such a model seems needlessly extravagant. It's the sort of thing that Occam's Razor was specifically invented to slice through. Assuming there's a simpler model of the universe that accounts for everything we know to be true, and assuming that this model adds no new insights, it fails.

But what if it doesn't fail? I'm in no position to judge one way or another, but what if the numbers bear out Julian Barbour's configuration space? What if his model is more consistent with what we know to be true about the universe than any other, and even provides fresh insights?

In that case, we would have to accept it, even at the cost of some of our most cherished building blocks of reality.

This example brings to light the twin dangers we face in putting together our individual working models of the world. We want to get to the truth, but we are dogged on both sides by our sense of the way things should be. This aesthetic sense can drive us to accept an idea that is irrational but poetic, or to reject an idea that is rational but that seems overwrought or too challenging to the status quo.

In his analysis of the scientific "provability" of atheism, Steven den Beste writes:

In any situation in which you make observations, you always have to take into account that the questions that you ask, and the means by which you try to collect data to answer the question, have the potential to distort the data you collect. Sometimes that distortion is systematic.

I would suggest that this distortion is inherent as often as it is systematic. To a large extent, we believe what we want to believe based on our individual tastes, deriving the rationale for our conclusions from the evidence we choose to emphasize. This might seem like a sloppy approach to getting at the truth, but I think it's one of the strongest advantages we have in the evolution of human thought. Most new ideas are really mutated versions of earlier ideas. The rate at which ideas mutate provides tremendous variety within the human thought space. This variety provides a large pool of traits (ideas) that the species (belief systems) which occupy this thought space can draw from.

Rational ideas can support irrational belief systems, and vice versa. Creationists can use the second law of thermodynamics to argue against evolution (the question of whether their arguments are valid is beside the point.) Or I can use an old Twilight Zone episode to help explain an arcane area of theoretical physics.

In other words, I think we benefit tremendously from the fact that no theory or belief system—atheism, Anglicanism, many-worlds, Barbour's configuration space, or anything else—enjoys the position that zealots might claim for it. There is no system of belief that is overwhelming and undeniable on the face of it. Nobody has to be stubborn or stupid or obstinate in order for disagreement to occur. All it takes is that we all be human. And because we humans do tend to disagree, the resources that we have to draw from when developing new modes of thought are all the richer, and the chance that we may yet one day wrap our minds around the most subtle and elusive of truths grows all the stronger.