A universe of universes?

> <!-- Blurb --><span class="smallHeader">Astronomy professor Alexei V. Filippenko posed the question, &quot;Could it be that ours is not the only universe?&quot;<span>
> <br> By Jack R. Sibley
> <span class="dateText">(April 1, 2001)<span>

In a recent lecture titled,, "A Universe of Universes? Reflections on Life, Theology, and the Cosmos," Dr. Filippenko of U.C. Berkeley posed the question, "Could it be that ours is not the only universe?" He began by reminding the audience at the Texas Woman's University that the entire history of our universe May be just an episode in the much grander, perhaps infinite "multiverse". This view is that there are scientifically valid reasons based on quantum theory and grand unification of forces to think that other universes might exist. But this interesting conclusion by its very nature removes itself from the realm of science, at least temporarily, because there is no known way to contact other universes and perform experiments on them, even in principle. Thus, at present, we can only speculate about the "multiverse".

And, at the same time, our very existence May permit us to draw some important inferences about the universe for example, that it contains elements heavier than hydrogen and helium. Such deductions utilize the "anthropic principle" which is the notion that we exist, therefore the universe must have certain properties or we wouldn't be here to see it. The values of the physical constants, not to mention the laws of physics themselves, seem to be spectacularly "fine tuned" for life as we know it indeed, almost "tailor made" for human habitation. In many cases, if things were altered by just a small amount, the results would be disastrous for life. The universe would be "stillborn" in terms of its complexity.

Some people use such cosmic coincidence to argue for a special, divine Creator. This is an interesting and perfectly defensible theological conclusion, and it May well be true, but it is not testable by the methods of science. Or, one May say that there is only a single universe, and it has these seemingly special properties by chance. Though possibly true, this conclusion seems difficult to accept; the odds against it are astronomical (pun intended), if most other allowed combinations of physical constants lead to conditions unsuitable for life.

Finally, one could suppose that there is an ensemble of universes, perhaps even infinitely many, which span a very wide range of properties. We, of course, happened to have been dealt a winning hand indeed, a royal flush inasmuch as we live in a universe that allowed life and sentient beings to develop. Such universes May be exceedingly rare, but not unique; most random hands are not winners, but some are. This line of reasoning is consistent with the conclusion mentioned before, based on other physical elements, that multiple universes might well exist regardless of the implications of life as we know it.

Filippenko concluded his remarks by proposing that although it is an example of the Copernican principle applied to the grandest imaginable scale, the multiverse idea is not currently testable according to the rules of science and thus lies more in the realm of philosophy and theology. Thus, it would appear that we are still left with the ultimate question, "How and why did the universe (or the multiverse) occur?" Perhaps there is no way, even in principle, for humans to definitely answer this question.

Jack R. Sibley, Ph.D., is a professor of philosophy and religious studies, Texas Woman's University.