[...]
Sciama quote:
>> ===================================================
>> This simple but powerful argument leads us to ask the question:
>> *how much* can I deduce about the universe from the fact that
>> I exist? It turns out that various elementary particle, nuclear,
>> atomic and molecular properties of matter have to be very finely
>> tuned for conditions in the universe to have permitted my
>> development--many examples are given by Barrow and Tipler and
>> elsewhere in this book. These finely tuned properties will
>> probably also eventually be accounted for by fundamental
>> theory. But why should fundamental theory _happen_ to lead
>> to these properties?
>>
>> There seem to be three possible answers to this question:
>>
>> (a) It is a complete chance.
>
Randy:==
> This answer doesn't seem very scientific to me since the probability of
>this being coincidental is so vanishingly small.
>
I agree, but perhaps for a different reason. It becomes problematic
to speak of fine-tuning in terms of probability. For one thing,
we have only one universe. Does it make sense to talk about
probabilities when the sample size is one?
But fine-tuning, as defined in the AP literature, is not tied
to probability, except perhaps in special cases. To get a
glimmer of this consider carefully Sciama's comment in the
quote above: "These finely tuned properties will probably
also eventually be accounted for by fundamental theory."
Now, some hold out a hope that if this eventuality comes
to be, then the fine-tuning "problem" will be solved.
The reason for this is most likely that so many confuse
fine-tuning with improbability. If the fine-tuning is
accounted for by "fundamental theory" then they are no
longer "coincidental" in a certain respect. They are,
however, still finely tuned wrt life. Note that Sciama
goes on to say "But why should fundamental theory
_happen_ to lead to these properties?".
Having a fundamental theory which accounts for all the finely-
tuned parameters does not explain why these finely tuned parameters
are those required for life. Sciama remarks that if indeed there
is a fundamental theory which gives rise to finely tuned
parameters one could still seek to "explain" this with the
"many worlds" hypothesis by supposing that each universe has
its own "fundamental theory" which leads to different parameters
not meeting the finely tuned specifications required for life.
One then applies the anthropic selection principle to say that
we shouldn't be surprised to find ourselves in the universe
with a fundamental theory that leads to parameters finely tuned
for life. We couldn't very well be in any of the others. :)
OK, suppose the fundamental theory which leads to a finely-
tuned universe is unique. Again, some have proposed this as
the death blow to the design argument based on fine-tuning.
But this turns out to be Sciama's worst nightmare. If the
fundamental theory is unique then introducing "other worlds"
fails to do the trick since every one of these is the same.
Since they're all the same there is nothing for the anthropic
selection principle to select from. A very interesting twist
to things.
OK, back to the main point. When someone says something
is a complete chance they don't necessarily mean "chance"
as used in probability. They may just mean that something
occurs for no apparent reason. It just happens. That's just
the way it is. I think this is the way Sciama was using the
word chance and thus I agree that this is not a particularly
good scientific answer.
>Sciama:==
>> (b) God regards me as such a desirable product of the universe
>> that he has fine-tuned it so as to guarantee my development.
>
Randy:==
> This seems like the best answer to me, although I don't know if it's the
>best scientific answer.
>
Very good answer. I also like this answer best but am cautious
about the scientific merit of the explanation.
>Sciama:==
>> (c) There exist other, disjoint, universes with other laws
>> and constants of nature.
>
Randy:==
> This answer also seems unscientific since there is no evidence(as far as
>I know) for the existence of these other universes.
>
Yes, another good answer. For some reason Pim has seen fit to
criticize your answers. I can't really understand why except
that its just part of Pim's nature to play the role of the
infinite skeptic :). As far as I'm concerned, the AP lies just
outside the bounds of science. All three answers are not
really satisfactory from a scientific point of view.
[...]
>> Brian:==
>> Evolution would not explain fine-tuning, rather, most fine-tuning
>> has to do with the required conditions for life to evolve.
>> IOW, fine-tuning seems to me to fit in nicely with design from
>> evolutionary creationist perspective :).
>
Randy:===
> If I'm understanding you correctly here, you're saying that evolution by
>itself would not account for the fine-tuning of the universe but that
>these phenomena would make sense to a theistic evolutionist.
>
Yes, see Howard's recent post. He says it much better than I
ever could.
Brian Harper
Associate Professor
Applied Mechanics
The Ohio State University
"He who establishes his arguments
by noise and command shows that
reason is weak" -- Montaigne