Saturday, December 20, 2008

Anthropic Arguments

Recently, I've been reading a book titled "Many Worlds In One" by Alexander Vilenkin - excellent review on Cosmic Variance. He explores deep cosmological concepts like the big bang, multiple island universes we'll never see, inflationary universe expansion, repulsive gravitational matter and a bunch of other cool shit.

But the chapter I'm currently reading speaks to the growing trend of anthropic arguments being made by physicists, philosophers and the like regarding the seemingly "remarkable fine-tuning" of the important physical constants of the of the universe. Some of the constants in question are the speed of light, strength of gravity, charge of the electron and the expansion factor of the universe (Cosmological Constant).

Anthropic-based reasoning suggests that these physical constants are precisely tuned to allow carbon-based life forms to evolve -- and hence -- this suggests the workings of a Grand "fine-tuner" (i.e. God, Prime Mover, etc.) that has made the constants as such. The reasoning follows that if any one of these constants were a little lower or a little higher then there would have been no possibility for life to evolve for physical reasons (if gravity was just a little less then stars could never have formed ... if atomic charges were just a little different then no stable atoms could exist, etc.)

Here's a more formal definition of what is known as the Weak Anthropic Principle...
Weak Anthropic Principle (WAP): the observed values of all physical and cosmological quantities are not equally probable but they take on the values restricted by the requirement that there exist sites where carbon-based life can evolve and by the requirement that the Universe be old enough for it to have already done so. (The Anthropic Cosmological Principle by John Barrow and Frank Tipler, p. 16)

Believe me folks ... I love reading this shit and I'm no genius but every time I hear these arguments I always feel perplexed because it seems like some very smart people are missing (or dismissing) an important point -- an evolutionary point. The values of the physical constants of the universe are most definitely "tuned" for what we see around us today not because some entity fine-tuned them ... but because what we see today are the ONLY things that could have formed within the constraints of those values.

This is classic evolutionary theory .... Stars, galaxies, stable atoms, space-time, matter, energy and whatever else we find in this universe are the ONLY viable "solutions" that could have formed in our universal environment. This universal evolutionary "fitness landscape" only allowed matter/energy configurations that bounded by the physical constant values. As the universe expanded from the big bang and stars were given enough time to live and die in supernova; heavier, more exotic elements (matter configurations) were created because the environmental landscape allowed more complex configurations ... not because the environment was tuned to create them .... the environment ONLY allowed their "types" to be created.... no other exotic element "solutions" were allowed or "survived" -- given the constraints.

With these new exotic elements now flowing in our universe ... they provided new landscapes of possibility ... new potential for complex matter arrangements that never existed early in the universe. As more time progressed and new stellar bodies were formed from these heavier, exotic elements .... pools of co-located elements were formed and these pools provided the fertile grounds necessary for the orgy of permutations required to traverse these new matter configuration landscapes.

Life is a solution ... a very special solution .... a beautiful "local maxima" in this matter possibility landscape that somehow gained the ability to self-replicate and metabolize. But none of this needs a fine tuner explanation .. nor does it need the advent of a billion other universes to help us grasp it or feel better about it. Quarks, atoms, molecules, photons, were all viable solutions to the universal constraints because they were the only solutions the environment allowed.... the only solutions that "survived" the universal fitness function.

The more complex things we see such as stars, galaxies and life are just hierarchies of solutions upon older solutions to this universal matter/energy landscape. Given enough time ... who knows what can evolve ... arguably, the only physical attribute that we should revere .... is time.



Berty's Anti-Anthropic Principle (BAAP): the observed matter and energy solutions (including life) observed today are not exclusive solutions but are the most compelling and successful solutions to the universe's fitness function composed and bounded by the values of the physical constants. Dying stars and large temporal spans provided new pathways to the solution landscapes necessary for The "Carbon Life Solution" permutation to be traversed.

Life is a compound hierarchical solution based on older, simpler solutions
(quarks, simple elements, stable atomic nuclei configurations, etc.) that survived the universe's fitness evaluations since the dawn of the universe.

Life and large temporal spans provided new pathways to the solution landscapes necessary for The "Intelligence Solution" permutation to be traversed. Intelligence is just another in a series of compound hierarchical solutions based on their older, simpler constituent substrates (i.e. life).

I guess its only natural to ask what new "solutions" will be produced when hierarchies of intelligence are compounded over large temporal spans ---- ooooooh ---- sounds like the Singularity to me --- Kurzweil rocks.