Re: idealism vs materialism

["John S. Denker" <jsd@MONMOUTH.COM>]

Tucker Hiatt wrote:
> I am persuaded that the majority of physicists are still
> materialists.  I.e., they believe that external, objective reality
> exists, and that this reality unfolds according to some
> as-yet-not-fully-grasped set of natural laws.

I agree with the second sentence but not the first.
The second sentence is far from being a definition
of "materialist".

> More particularly,
> these physicists are materialists -- as opposed to idealists --
> because ...

Materialist is far from being the opposite of idealist.

> ... they believe that matter/energy is the fundamental
> constituent of the universe, not mind/consciousness.

Again, ruling out mind/consciousness is not evidence of
materialism.

...
> I am further persuaded that most modern expert interpretations of
> quantum mechanics (QM) have disposed of the necessity of a conscious
> observer to force the "collapse" of a wavefunction.  Interaction with
> other "sufficiently energetic" bits of matter/energy causes the
> collapse.

Yes, that's basically the right way to look at the physics.

> challenge, within the standard interpretation of QM, may now be to
> identify precisely what constitutes a "sufficiently energetic"
> interaction that turns quantum reality into classical reality.

What matters is signal-to-noise ratio.
A quantum harmonic oscillator can be treated
as a classical harmonic oscillator if its amplitude
is large compared to sqrt(hbar).

How large is "sufficiently" large depends on the
application.  When I plug a toaster into the wall
it is "sufficient" for toasting-purposes to regard
the 115V supply as classical, even though if you
looked closely enough you could see quantum fluctuations
on the voltage.