Wednesday, October 24, 2007

multiple universes:
a guarantee of human freedom?

What if our universe was one of a burgeoning, possibly infinite, number of universes? This article says:

Parallel universes really do exist, according to a mathematical discovery by Oxford scientists described by one expert as "one of the most important developments in the history of science."

The parallel universe theory, first proposed in 1950 by the US physicist Hugh Everett, helps explain mysteries of quantum mechanics that have baffled scientists for decades, it is claimed.

In Everett's "many worlds" universe, every time a new physical possibility is explored, the universe splits. Given a number of possible alternative outcomes, each one is played out - in its own universe.

A motorist who has a near miss, for instance, might feel relieved at his lucky escape. But in a parallel universe, another version of the same driver will have been killed. Yet another universe will see the motorist recover after treatment in hospital. The number of alternative scenarios is endless.

Science fiction writer Larry Niven explored such a universe in a short story titled "All the Myriad Ways" which can be found in a collection also titled All the Myriad Ways. To my mind, the many-worlds hypothesis remains firmly in the realm of the fictional, but let's put aside for a moment the issue of how plausible such a scenario is.

The idea of "myriad ways" is philosophically intriguing, not least because it seems to present us with the possibility that we are "branched" beings with ramified lives playing out in an ever-increasing number of universes. Does a many-worlds existence in which we are, from a godlike perspective, living through all possible outcomes, provide us with a model that affirms human freedom?

I would say no. First, we have the problem of possibility. It seems to me that, in such a scenario, there are no longer any true possibilities; even to say "all possible outcomes" is misleading. What we have, instead, is a scenario in which all events are actual. This is little different from the issue of divine foreknowledge, in which God's knowledge of what you do in five minutes is possible only because your future is actual to God. From a godlike perspective, predicting events in an Everettian multiverse is a snap: if you ask me whether I will choose Chinese food or pizza for dinner, why, the answer is obviously both! There will be an infinite (or, at least, a huge) number of universes in which I arrive at that exact moment of choice, and whatever choices are available to me will all be made. Such predictability does not seem to allow for freedom. Instead, what we see is yet another version of an inevitable unfolding. This inevitability won't be visible from the horizoned perspective of one "me" in one universe, but it will be visible from the godlike perspective. The inevitability will, in other words, exist objectively.

Second, I am troubled by the idea that choice is what produces fission. Why something so human as choice, and not the Heisenbergian movements of electrons? In fact, given the inevitability discussed in the previous paragraph, it seems difficult to affirm the idea of choice at all: if we follow the Everettian schema, then I, as a branching being, will explore all the pathways open to me at any given moment.

Turning now to the issue of the theory's plausibility, I submit that the many-worlds hypothesis is fit for slaughter by Occam's Razor. It generates far too much ontological messiness. Think about it: on August 31, 1969, Kevin is born. From that moment on (if not before), my exercise of will will produce new universes, all created-- poof-- by "choice" (more accurately, the simultaneous exploration of all available avenues). In many of these universes, I will die an early death, perhaps as the result of other people's choices. In many others, I will die as a teenager, or as a twenty-something, or as a senior citizen. But what's to say that the event of my birth on August 31, 1969 was unique? Perhaps in other universes created by my multitude of parents, I will be born, and multiple Kevins will begin living out their ever-branching lives. How can all of these Kevins be meaningfully tracked?

The above picture, multiplied by all the sentient, will-exercising beings that have ever lived, quickly becomes a royal mess. The mess isn't helped by the fact that the branchings, if caused by "choice," will in theory be governed by the number of available alternatives at hand. If so, it must be asked how one can know the number of universes that sprout from any given choice-point. "Pizza versus Chinese food" might seem a clear case of one universe splitting into two, but what about a more complicated scenario, such as a simple conversation? Assuming-- rightly, I think-- that any given conversation can spin off in numerous directions at any moment, how does the cosmos know what number of universes should spring into existence at each moment? This strikes me as an intractable problem for advocates of the many-worlds hypothesis.

So in the end, I don't see Everett's vision as hope for human freedom, nor do I consider it plausible, given the serious philosophical and scientific questions it raises. A scenario so completely lacking in simplicity and elegance strikes as me deeply counterintuitive and, it must be said, just plain wrong.



R said...

I've read that Larry Niven story I believe. That's the one where the cop is investigating the rise in suicides? People stepping off balconies because they think 'so what'? If I don't, in another reality I will...

Infinite realities do my head in. Just think, there'd have to be a universe somewhere where you lived forever...

Which would cause a whole lot of congestion among the planes of reality. The version of you that didn't die would continue spawning new universes with every decision made.

Do I veer slightly to the left with this step? Shall I have another mouthful of beer? Should I fart now or hold it in?

Perhaps I just can't comprehend true infinity...

John Mac said...

Okay, well, that was a little clearer to my muddled brain than the other post I read on this subject. So, my fantasy might still work--the universe doesn't split with every decision I make on the road of life, but at the end of that road, I get a do-ever, and my alternate choices create the alternate universe. The closer I come to the end of days, the more appealing my version of "heaven" becomes. So help me, God!