re: Physics Query

Garry DeWeese (deweese@ucsu.Colorado.EDU)
Thu, 11 Apr 1996 15:47:11 -0600 (MDT)

On Mon, 8 Apr 1996, jeffery lynn mullins wrote:

>
> Didn't Mackie, of fame for writing an atheistic apologetic in reply to
> Swinburne, come up with a theory of absolute space denying relativity on
> philosophical grounds?

Yes, Mackie wrote "Three Steps towards Absolutism" in _Space, Time and
Causality_, ed. Richard Swinburne.

> I have also seen some "hole" arguments from Earman that argues that to accept
> a substantivalist view of space one must deny determinism (this may not be
> exactly your topic, but is related).

Earman, I think, bases his views on taking the point manifold of GTR as
substantival spacetime. But a good case has been made for taking the
metric-field tensor as representing spacetime. The manifold gives
topology; the metric field tensor the geometric relations. (Which raises
the question: how could spacetime have a defined topology, and its
points have defined geometric relations, before the introduction of
matter/energy with the memontum-eneergy tensor?)

> This is interesting to me since
> modern cosmology seems to be saying that the expansion of the universe is
> an expansion of the space between the galaxies, not of the galaxies
> themselves, and thus could have exceeded the speed of light during an
> inflationary epoch. However, I haven't really had time to look into it.
>
This is interesting. I once asked a cosmologist about this expansion and
was told that rather than space expanding, new points of space were being
created to fill in. But then he muttered something about the dumb
questions philosophers ask ;^)

> I think that you probably will find more from scientifically informed
> philosophers of science than from physicists on the issue unless you look
> at physicists in the early part of the twentieth century. Once a
> paradigm is solidified the later generation brought up in that paradigm
> seems to take it at face value unless they are interested in the history
> and philosophy of science.
>
I think you are right. Few physicists today think about their field in
the philosophical way that Bohr, Heisenberg, Bohm, Schroedinger, etc.
did. It almost seens that even while proclaiming themselves
critical realists (at least cosmologists do; the quantum guys wink and
waffle), their actual approach is more operationalist. Or is that just
the ones around here?

Garry DeWeese