Friday, April 01, 2011

Middlebrow Atheism. Part 4

Continuing my series on naïve atheism:

Video Item 07: Cosmic “Fine Tuning” is not necessarily as fine as theists think. It is conceivable that other very different environments could host (generate?) life. For example it is now thought that the goldilocks zone in the solar system is not the only possible environment for life: Tidal forces on Europa, Jupiter’s satellite, could produce the “black smoker” environment needed to sustain life well outside the goldilocks zone. Similarly, how do we know that changes in the “fine tuning” constants can’t produce a life permitting universe? Alan Guth says he is not impressed by the fine tuning coincidences: We have no way to deduce from a suite of laws whether or not life will occur.

My Comment: The video is at its best and most subtle on this point. There is a significant issue here.

We’ve seen from previous posts in this series that it is very unlikely the laws of physics are merely an artifact of a selective human perspective on a huge maximally disordered super-universe. In fact it looks as though our cosmos is intrinsically constrained to favour order, for whatever reason. Alan Guth says on the video that he has no idea why the laws of physics are what they are, but whatever they are it is clear that those laws support life. In fact the least we can say is this:

1. The laws of physics provide a construction kit of fundamental parts which, given a suitable environment, permit the assembly of complex ordered self perpetuating configurations.

I don’t think many people could disagree with that. It is patently obvious that self perpetuating configurations can exist under our regime of law and disorder (Those configurations are called “life”). The following assertions, however, are stronger, less obvious and more controversial:

2. Given a suitable environment the laws of physics imply the mathematical existence of a class of self perpetuating configurations forming a large connected region in configuration space – that is, any two configurations are separated by a series of incremental configurational changes which constitutes a path through configuration space where every point on that path is a self perpetuating structure.
3. The aforementioned region of configuration space contains some elementary configurations of realistic probability.

The latter two conditions are a requirement of evolution and for that reason they set alarm bells ringing amongst the anti-evolutionists; their commitment is to irreducible complexity which effectively negates assertions 2 and 3 above. Anti-evolutionists will, of course, accept that the cosmos is fined tuned to sustain life, but not that it is fine tuned to generate life. However, since most atheists are evolutionists I’m going to proceed by assuming these assertions are not problematical. I’m running with the atheist mindset here and seeing where it takes us. In order to get a handle on this matter I assume we are only dealing with physical laws covered by the Church-Turing thesis; that is, physical regimes whose functions can be rendered computationally. I also make the assumption that we are only dealing with suites of laws which can be specified using relatively few bits of information.

The video asks the question:

How do we know that changes in the fine tuning constants can’t produce a life permitting universe?

But why ask this question? What difference does its answer make to the atheist position? The answer to the latter questions is, I believe, answered in my last post on Cosmic Symmetry Viz: There is an implicit and instinctual theology at work here which intuits that if it can be shown our cosmos is not a particularly unique case then this helps support the atheist cause, or at least gives the theists a lot less to crow about. In contrast very special and singular conditions strengthen the theist case by giving the cosmos the touch and feel of intelligent contrivance. Hence if it can be shown that life sustaining/generating conditions are a consequence of most systems of physical laws, then it will be no surprise that our particular physics supports life and the problem of life’s existence seems less likely to be the result of intelligent selection.* On the other hand if amongst the possible suites of physical laws life supporting regimes are very rare then the case for intelligence selection (or a “put up job” as Paul Davies once put it) is intuitively strengthened. So, the pertinent question is this: Is our physical regime one of a very rare breed or is it in no way a special case amongst the possible systems of laws?

Trouble is, asking this question is one thing, answering it is quite another. In this connection Alan Guth makes a very apposite observation. He says that given a suite of physical laws nobody knows how to deduce whether or not life will exist as an outcome of those laws. In fact even given our own well known physical laws it is unlikely we could do this in advance. If evolution has occurred, I suspect that it is one of those computationally irreducible processes that Stephen Wolfram talks a lot about – that is, there is no shorter analytical way of showing that a given suite of laws implies evolution other than to simulate evolution in its entirety in a computation. If evolution is computationally irreducible it is no surprise then that Guth (or anyone else for that matter) has no idea how to do the calculation in a shorter number of steps than the process of evolution itself could do it. But it’s even worse than this: Above I have assumed that the suites of physical laws we are considering can be specified using relatively few bits of information; perhaps a few hundred Kbits of information. But even this relatively small number of bits creates a search space far too large to be humanly tractable; there are far too many suites of physical laws for us to find, let alone trial run to see if they generate life.

Given these difficulties it looks to me that the question of whether or not life supporting physical regimes are common place and passé is not going to be easy to answer; in fact it is probably, an intractable problem. So, my conclusion here is that no firm conclusions can be drawn on this subject; at least not at the moment. (But see footnote **)

However, the discussion so far does give us insight into human theological intuitions. If life is a result of the selection from a class of rare life supporting cases when all cases otherwise seem to be equally possible, this is usually taken to be grist to the mill by the ID theorist. By attempting to deny the very singular nature of a cosmic physical regime which clearly at least sustains life the video is effectively acknowledging that the ID theorist’s design detection algorithm has a certain persuasiveness about it; why else would they see the need to downplay the significance of life supporting conditions by proposing that other physical regimes might support life? I suspect that the atheists behind this video feel very uncomfortable with the idea that our universe may be fined tuned in the sense that it has been selected for reification from a remarkably unique class of life supporting scenerios. The atheist’s game here is to promote that idea that a life supporting cosmos is too common place to warrant the “fine tuning” epithet; in showing the need to classify “fine tuning” as “wrong” rather than “not even wrong” they are actually betraying how compelling “fine tuning” can be if and when we should stumble across it.

* Although, of course, the problem of sheer existence remains open; that is, the old “why is there something rather than nothing?” type question.
**My guess is that if evolution is possible then the physical regimes that support it are very rare indeed. If this guess is correct and if life on planet Earth has evolved then it follows that our universe is governed by a very significant set of laws. This would mean that the cosmos is highly asymmetrical; that is amongst all the possible    physical regimes that seem to have an equal claim to existence our life supporting regime is the one that has, for some reason, been singled out for ontological reification.

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