Why is our universe here?

(Sorry, faithful readers, but I’m simply in a philosophical mood lately!)

This is one of the classic questions in philosophy: Why are we here? Or, adding evolution to the picture: Why is our universe here?

My standard response to this sort of question is a strong form of the anthropic principle, combined with an appeal to the notion that all logically consistent universes may lay the same claim to existence, which is (at least to me) much more intuitively reasonable than the notion that our universe is the only one, and we’re awfully lucky that it isn’t a game of Tic-Tac-Toe instead of the four-dimensional curved spacetime that it is, thus allowing the materialistic diversity for an intelligent species to someday evolve. We’re not “lucky,” this is simply the only universe of infinitely many in which we naturally evolved, so here is where we are.

But I have recently discovered a fundamental flaw in this position which presses me to re-evaluate it. The necessity of a habitable planet, suitable molecular dynamics for cells and brains, etc., does not adequately explain, for instance, why there are so many stars around. Would not a single sun, with a single Earth, be enough for life to evolve? Why all this junk? Ockham’s razor would suggest it would not be likely to appear at all, let alone in the vast quantities it does.

To resolve this, I must amend my egalitarianism towards universes. Perhaps the “degree of existence,” or the likelihood that a given universe exists, is dependent on the number of bits necessary to specify it - the a priori information content that must be granted to such a universe before we can begin to derive what might happen within it. If you wish, you can imagine a universe being drawn randomly from an infinite hat, containing all the natural numbers, where the universe is interpreted by means of a Universal Turing Machine. The fewer bits are necessary to specify a given dynamics, the more likely it is that the universe drawn from the hat will be isomorphic to said dynamics.

In this case, the existence of myriad stars and galaxies can be explained by the fact that it was a very simple disturbance to a highly compressible pattern that caused the Big Bang, making it far more likely to have been drawn from the universe hat than a universe which specified, in intimate detail, the exact configuration of a single solar system as its initial conditions. Similarly, the existence of a huge number of layers of abstractions of physical dynamics (e.g. quantum physics, chemistry, biology, anatomy, Newtonian physics, psychology), and the resulting applicability of reductionism to science, can be explained in this framework as a shortcut to specifying the upper layers - those governing conscious observers - directly. Weirdness about the curvature of spacetime can thus be chalked up as compression artifacts - just cosmological moire patterns. Essentially, this promotes Ockham’s razor from an instrumental rule of thumb to a fundamental metaphysical principle: to be likely to exist, a given system must have a simple description.

Note that this explanation says nothing about the weirdness of wave-function collapse, and its apparent ties to conscious observers. I consider these ties to be truisms, and illusions at best, due to the many-worlds theory. I will continue to elaborate on this aspect of my philosophy in my next post, The Arrow of Time.