The Explanatory Power of the Multiverse?

Previously: In Why Does the World Exist? Jim Holt is continuing to report on the different approaches to the question, "Why is there something instead of nothing?" He speaks to scientists, philosophers and mathematicians, and finds both compelling aspects and holes in each perspective.

Holt moves to the multiverse model to present the idea that if "anything that can happen, will happen", then it is hardly surprising that the universe happened. Turns out there are multiple conceptions of the multiverse, which I will not review here, as the multiverse is an area of my special interest, and I have a lot of other ground to cover. However, although the multiverse addresses the "fine-tuning" issue (how does our universe just happen to have the right mathematics to support life?), it still doesn't really address the fundamental question: How did we get something from nothing?

Holt turns to mathematicians for their take. As fans of Neal Stephenson's Anathem know, there is a school of mathematics that believes that "mathematical forms indeed have an existence that is independent of the mind considering them" (Rene Thom, quoted on p. 173). Other mathematicians do not agree with this perspective and see their work as either describing things that they observe (applied math) or imagining other, logically consistent but perhaps physically impossible constructs (like the square root of -1-- this is "pure" math). Either way, there is a case to be made that our reality can be described strictly in terms of mathematical relationships between forces, in which case, it could be conceived as the product of an infinite mind, contemplating possibilities.

This is the theory subscribed to by John Leslie. If you think about Plato's cave again, then, if the shadows on the wall are our reality, and we are the people chained facing the wall, and the pure mathematical forms are the objects of which we only see the shadows, this infinite mind is the sun that casts the shadows. Then, of course, we are back to the God Hypothesis, but rather than an image of God forming things out of chaos and mud, we have the more 21st century image of Him creating them out of the matrix of His own mind. Is there much substantive difference between the two conceptions?

Derek Parfit, who is primarily a moral philosopher, has recently interested himself in this problem of origins, and his contribution is to start from the how and work into the why, considering all the possible realities including our own and asking ourselves what cosmic possibilities might be true. There could be nothing at all (but obviously there's not). There could be one universe or a lot of universes, and it or they could be designed or selected to be good, bad, or indifferent; simple or messy; similar or different; and so on. Perhaps all possible worlds exist, in which case ours, with all its flaws, requires no explanation. Just as some people have to live in North Korea and some people get to live in Hawaii, so some beings have to live in this entropy-driven universe and this fallen planet, while presumably somewhere beings are enjoying a more uniformly good existence, and some poor creatures are perhaps suffering an even worse one. But again, what drove all possible worlds to exist? I feel that we continually, contrary to one of Holt's earlier sources, run up against a wall with no door marked "NO EXPLANATIONS BEYOND THIS POINT."