This is a good question whose answer depends on which parameters
are supposedly fine-tuned and how they attained their values during
the early formation of the universe. As I understand it, the predominant
view is that certain parameters are attained due to symmetry breaking,
wherein only one of many possible branches is followed for no
apparent reason, e.g. the process is stochastic rather than deterministic
and the various parameters arise independently of one another.
If this is correct, I think its appropriate to discuss different possible
universes that vary only in the value of a single parameter.
One of the things I like about the Anthropic Principle (AP) is that
it seems always to be full of surprises. Most people who advocate
design simply abhor chance, yet it seems from the above it is
only chance which keeps the AP design argument alive in the
face of the criticism posed by Steve. Leslie has argued that the
design argument from fine-tuning is not particularly consistent
with Creationism, and I tend to agree. Here's an example from
Leslie:
The argument from design tries to prove God's reality by
examining the universe. In the form given to it today by
those naming themselves "creation scientists" it earns the
fury of genuine scientists. I shall show why most reputable
thinkers consider it long dead and buried. But afterward I
plan to demonstrate that recent developments make it very
much alive, though not in any shape creation science would
welcome.
-- Leslie, J. (1985). "Modern Cosmology and the Creation of
Life," in <Evolution and Creation>, Ed. E. McMullin,
University of Notre Dame Press, pp. 91-120.
After having said the above let me add that I don't think the
criticism posed by Steve really undoes the anthropic argument
even if it were shown that there is some GUT from which all
parameters are attained deterministically. My musings along
these lines were stirred by an article by Dennis Sciama and
also influenced considerably by Paul Davies and Owen Gingerich.
First we have to make a slight digression to avoid confusion
over terminology. Fine-tuning, the way its generally used in
the AP literature, is independent of process. Parameter x is
said to be fine-tuned wrt to y if the occurrence of y requires
x to fall within a very narrow range. Thus fine-tuning is well
established and the question we are really interested in is
whether we should consider this fine-tuning as surprising in
any way. Thus, to re-phrase Steve's criticism we say that we
shouldn't be surprised to observe these finely tuned parameters
since they are predicted precisely by our GUT. So, my argument
will be that maybe we should still be surprised.
First we observe that there is no reason to suppose that our
as yet undiscovered GUT is the only possible GUT. It could be
the there are multitudinously many GUT's with most GUT's
yielding Universes that would be lifeless. For some reason this
possibility seems to escape most people, but unless we commit
the heresy of saying that life is somehow special then we would
have to admit the possibility of lifeless GUT's [ :) ]. OK, so now
we have to entertain that pesky anthropic question. Out of all
the logically possible GUT's why does our Universe just happen
to have a finely tuned GUT [by finely tuned GUT I mean only a GUT
which yields parameters in the very narrow range required for life].
Now, the standard way out of this dilemma is to propose the
Many Worlds hypothesis. There exist an extremely large number
of universes each with its own GUT. This being the case we should
not be surprised to find ourselves in a universe with a finely tuned GUT.
After all, we couldn't very well be in one of the other universes.
This last is called the anthropic selection argument. It is absolutely
essential to recognize that invoking this argument requires not just an
argument that other universes are logically possible, they must
actually exist else there is nothing to select from. This is
important since it is common to see someone use anthropic
selection and at the same time refuse to admit they are appealing
to Many Worlds.
Well, arguments along these lines come to an end at this point
as far as I'm concerned. As a theist, I tend to prefer the
God hypothesis to the Many Worlds hypothesis. But I'm not
going to argue with an atheist who prefers the Many Worlds
hypothesis. With only a very few exceptions I'm convinced that
no one is going to find God by going through mental gymnastics
such as these. As Pascal wrote in his wonderful "Memorial":
" 'God of Abraham, God of Isaac, God of Jacob', not of
philosophers and scholars."
Along these lines I really like a slight paraphrase of another
Pascal saying:
It is good to grow tired and weary of endlessly seeking
after God, so that we may stretch out our arms to the
Redeemer.
Pascal actually wrote "endlessly seeking to do good", but I
don't think my modification distorts his meaning.
But :), I'm not quite done with the AP yet. A seemingly good
counter to the above arguments is to suppose that there is
only one logically possible GUT. I got a really big surprise
when I found that this possibility is Dennis Sciama's worst
nightmare in the article I mentioned above. Why? Remember if
we rule out the possibility that life is special, there is no
reason to suppose that a GUT should yield the finely tuned
parameters required for life to exist. But now we learn that
there is only one logically possible GUT and that it is finely
tuned. Worse yet, we cannot appeal to Many Worlds because
even if they existed they would all be the same. In other
words, anthropic selection fails here since there is nothing to
select, every universe is the same.
I find all this to be fascinating. From a theological point
of view I find this last possibility [only one logically
possible GUT] quite disgusting ;-). It is very amenable
to a deterministic, mechanistic view wherein there is no
freedom and no free-will. Thus, most likely to the disdain
of many, I prefer a random chaotic universe. Well, I'm
not going to elaborate on this anymore since I've gone on
way too long anyway. I'll just say that, lest anyone think
me some kind of heretic, that I use the words random
and chaotic with their technical definitions in mind and
not the meanings generally attributed to these words in
everyday conversation.
Brian Harper | "If you don't understand
Associate Professor | something and want to
Applied Mechanics | sound profound, use the
The Ohio State University | word 'entropy'"
| -- Morrowitz
Bastion for the naturalistic |
rulers of science |