In my last post, I gave a very general explanation of how the universe seems fine tuned for life. This is not a matter of biological fine tuning (though evolutionary models are a whole separate issue which, so far as I can tell, lend themselves to the same kinds of questions), but fine tuning of the most basic laws of our universe. You’ll have to read that post to follow along with what follows.
Van Inwagen believes that we have no reason to prefer either the “creator” hypothesis or the multi-verse hypothesis, but I disagree.
There are two possible scenarios in the multi-verse hypothesis. One is that there are a limited number of possible cosmos, the other is that there are an infinite number.
There are serious problems with proposing an infinite number of actual cosmos, infinite we might say. This excerpt from an article in Scientific American sums them up well:
The most popular cosmological model today predicts that you have a twin in a galaxy about 10 to the 1028 meters from here… The estimate…does not even assume speculative modern physics, merely that space is infinite… There are infinitely many other inhabited planets, including not just one but infinitely many that have people with the same appearance, name, and memories as you.”(1)
This was still a misrepresentation of the state of affairs among physicists at the time, but still, the problem of proposing that there are an infinite number of universes is that if the above scenario is true, we come up with ludicrous situations. If it is true, there is bound to be a universe to match absolutely any possible scenario we can think of. Consider this one posed by Oxford philosopher Nick Bostrom in his book Anthropic Bias:
“When black holes evaporate…things such as boots…have some finite probability of popping out…there is thus a finite probability that a black hole will produce a brain in a state of making any given observation…even “uninhabitable” universes can con taint the odd, spontaneously materialized “freak observer”…It is even logically consistent with all our evidence that we are such freak observers”
While Bostrom’s last sentence would make absolutely no sense if the scenario he just described is actually the case, since there would be no “we” to speak of, the fact is that this scenario leads us straight into the worst kind of skepticism, the kind that is existentially untenable. You might be the freak observer, and everything around you is simply the state of your brain. It could be the case that there are no laws of physics, most of what you think you know about the world would be false, and there’s no way to verify it because you cannot “get out” of your experience as this singular observer. You cannot bring in your memories to ward off this possibility, because they are part of that moment, or moments, of spontaneous existence. It is impossible to live with the skepticism implied in this hypothesis.
But, what if there a limited number of universes, an extremely large amount of them? Well, string theorists have been at the forefront of the multi-verse hypotheses because the strong theory model of physics “yields a gargantuan number of models: about 10,500, give or take a few trillion”(2). For Leonard Susskind (a founder of string theory) an proponents of the multi-verse, each of these different possibilities in the model is an actual existence universe somewhere. But there is one huge hurdle facing the multi-verse hypothesis in any form. David Gross, a Nobel prize winning theorist put it simply: “It’s impossible to disprove”(3). Gross further claims that because we have no way to get out of our own universe and falsify whether there are others, the theory itself isn’t science (ibid). He isn’t alone either.
Lisa Randall at Harvard claims “You really need to explore alternative before taking such radical leaps of faith”. Astronomer Bernard Carr says that the reason Gross (and presumable other scientists) do not support the multi-verse hypothesis is that they see
“science taking on some of the traits of religion… In a sense he’s correct, because things like faith and beauty are becoming a component of the discussion” (ibid).
This will get to the heart of the issue “Gross believes that the emergence of multiple universes in science has its origins in theorist’s 20-year struggle to explain the finely tuned numbers of the cosmos” (ibid). Because of this, Gross and others are actually at work to find some way to refine the equations of string theory, and discover a “theory of everything”, which would exclude the multi-verse hypothesis, but at the same time weaken the plausibility of a Creator of the cosmos. In response to this, string theorists like Susskind have said that they may be “looking for meaning in a meaningless set of numbers” (ibid). Which leads us back to where we began; it is a fact that the universe is fine-tuned for life to exist. Corey Powell, a senior editor of Discover magazine, interviewed Leonard Susskind and makes this keen observation
Susskind embraces the megaverse interpretation because it offers a way through the intelligent design challenge
I believe that anyone who looks at the same facts squarely in the face will be blown away by the universe’s suitability for life. The reason that the “multi-verse” interpretation has emerged is not an empirical one, it is metaphysical.
In my next post, I’ll elaborate on how that is obviously the case (if it’s not clear already), and on an argument that I believe gives belief in a creator much more plausibility than mere emotional appeal.
(1) Tegmark, Max. Parallel Universes. Scientific American. May 2003. <http://www.scientificamerican.com/article.cfm?id=parallel‐universes>.
(2) S. Powell, Corey. THE COSMIC LANDSCAPE String Theory and the Illusion of Intelligent Design. The New York Times. Jan 20 2006. <http://www.nytimes.com/2006/01/20/news/20iht‐booksat.html>.
(3) Brumfiel, Geoff. Our Universe: Outrageous fortune. Nature. January 05 2006. <http://creationism.org.pl/groups/ptkrmember/filozofia‐ przyrody/2006/document.2006‐01‐30.0746182444>.