By Aaron Davidson
The physics of the known universe seem strikingly convenient. It is almost as if they have been fine-tuned to allow for the existence of complex systems and self-organizational dynamics. Physicists have devised hypothetical experiments to examine the consequences of changing the constants of the universe. By changing the speed of light, or the strength of gravity by even small amounts, it seems that the universe would be a much more hostile place. Complexity, the organizational state between stagnant order and turbulent chaos, is a requirement for life as we know it. If gravity were too weak, stars and galaxies would never have formed because the necessary cohesion would be missing. If gravitational forces were too strong, stars would form, burn and collapse too quickly for any stable systems to develop. The laws of physics posses a beautiful balance without which we would not be here to discuss its marvelousness. It appears that the finely-tuned nature of the cosmos is much too improbable to have happened by chance. It must, says the Teleological Argument, have been designed to support complex systems.
Utilizing our own existence in cosmological arguments is known as anthropic reasoning and arguments such as the above are grouped under the term the Anthropic Principle. The Anthropic Principle comes in strong and weak forms. The Teleological Argument above is analogous to the Strong Anthropic Principle. The Weak Anthropic Principle concludes that if the universe had possessed laws that did not allow for life to exist, we would not exist. Conversely, if the universe, by chance, did posses laws that were life-friendly then we could exist. Since we do exist, then it must be the latter case. If x is a necessary condition for the existence of y, and y exists, then x exists (Dennett, p.165).
There is a flawed version of the Weak Anthropic Principle which says that it was pure chance that the universe formed so perfectly. While this can be argued without logical contradiction, our intuition tells us that the fact that we are here is such a highly improbable event that it requires some further explanation as to why it happened. It is the counter-intuitive nature of this argument which invokes van Inwagens scathing comment denigrating it to be one of the most annoyingly obtuse arguments in the history of philosophy. While we can use ourselves as a proof that a universe supporting life occurred, this does not prove that it had to occur.
I reject the Teleological Argument/Strong Anthropic Principle because it postpones the question by concocting the existence of a designer. A designer cannot explain away improbability a designer is even more improbable than the designed. The Teleological Argument explains nothing and is fundamentally flawed in its logic. In order for life to exist, the universe must have certain necessary properties, but it does not follow that the universe has those properties for the purpose of creating life. Likewise, since we exist, it must be true that the universe has certain properties but it is incorrect to say that since the universe has certain properties, we must exist.
The Weak Anthropic Principle is not very useful in itself since it merely states a fact about our universe without explaining anything. The Strong Anthropic Principle can be rejected for the reasons outlined above. What remaining options are there to explain the fine-tuning of the universe? What needs an explanation is the improbability of our universe being the way it is. The improbability rests on there being only one universe ours. What if there were many universes? As the number of different universes which exist increases, the probability of at least one of those universes being able to support life increases as well. One could imagine the possibility of more than one universe existing just as easily as one could imagine just one existing. Since there are an infinite number of ways of imagining multiple universes and just one way of imagining only one universe, then it is more probable that there are many universes rather than only one. Perhaps every universe that could exist does exist. In any of these situations, the improbability of there being a universe just like ours is dissolved.
As it turns out, astrophysicists have not overlooked this idea when constructing their theories. One such theory requires just one universe in order to make our universe probable. Since we have eternity to work with, the theory postulates an endless cycle of experimental runs of the same universe, but with new physics each time. After a big bang, the universe expands rapidly. It may expand indefinitely, or it may eventually stop expanding and collapse back upon itself in what is termed a big crunch. If this is the case, a big crunch starts off another big bang. Each time a big bang occurs, the laws of physics vary from what they were before. If this cycle went on for all eternity, then at some point we would find ourselves in a universe not unlike this one.
Lee Smolin, a theoretical physicist, has found a way in which a process similar to Darwinian evolution could occur with universes. When a black hole forms, it may be possible that it creates a brand new universe within itself a whole new package of space and time equally impressive in scale to our own. The new universe would likely have similar properties to our own, but small mutations could occur. It would stand to reason that through this process, universes with physics that can create numerous black holes will have a proportionately higher amount of offspring. This means that most universes existing would tend to have physics which optimize the amount of black holes they can produce. It just so happens that the laws of physics in our universe are particularly good at forming black holes. If we experiment with physics differing from ours, we find that such universes would more often than not produce less black holes than ours. One of the requirements for abundant black holes is a carbon rich universe, which coincidentally is also what is needed for life. Smolin has found a possible way to have a type of natural selection occur on a universal scale. If Smolin is correct, it is no longer a big mystery as to why the universe we find ourselves in has such perfect physics it would be the most probable type of universe that there is (Brockman p.287).
Drawing from simple thought experiments about multiple worlds to ideas in theoretical physics, the fine-tuning of our universe can become a much more probable event than it initially seems. The Teleological Argument, or Strong Anthropic Principle attempt to resurrect the classic Argument from Design. Rather than address the designs of life, it points out the designs of basic physics, and just as Darwinian thinking showed how design need not require a designer, there are similar ways to account for the physics of this universe. With this and other possibilities, the Teleological Arguments conclusion that there must have been a designer loses its force.
Brockman, John. The Third Culture: Beyond the Scientific Revolution. 1996. Touchstone Books, New York.
Dennett, Daniel. Darwins Dangerous Idea. 1995. Touchstone Books, New York.