At 10:56 PM 12/10/2000 -0500, you wrote:
> >>>Chris Cogan: The results of the experiment are fantastic, wonderful,
>exciting. But they don't invalidate determinism. My initial claim stands.
>It's not even logically possible for empirical evidence to invalidate
>indeterminism as such. It is only possible for it to invalidate *specific*
>claims of determinism (such as Einstein's, in this case), claims in which a
>specific causal relation is asserted. If that specific relationship does not
>hold, we may be able to show it empirically. For example, if I claimed that
>the way dice landed was determined completely by the positions of the planets
>(and gave a formula or other means of specifying the outcome of a throw of
>dice based on the positions of the planets), it would be easy to test whether
>this was true or not.
>
>But, if we determined that it was not true, we would not be justified in
>saying that the dice behaved in a truly indeterministic way; there might be
>*other* causal factors at work that determine the way the dice land.
>
>
>******************************
>DNAunion: Okay, I might be misinterpretting your statements, but it sounds
>to me like you are saying determinism cannot be empirically invalidated in
>any experiment (if I am wrong, let me know).
Chris
No, you've got it right.
DNAunion
>If that is your positions, what about the infamous double-slit experiments?
>
>When a beam of light (stream of photons) is "shot" though a double-slit
>apparatus, the result is a wave-inteference pattern on the detector (bands of
>high concentration of photon hits interspersed at regular intervals with
>bands of low concentration of photon hits). That is, the light acts as a
>wave, with constructive and destructive inteference properties.
>
>But if only a single photon is "shot" through the double-slit apparatus,
>where will it land on the detector? Without any other photons to interact
>with, their can be no wave-like constructive and destructive interefence to
>consider, and the photon should behave like a solid particle - following an
>absolutely straight path and striking the detector (in a manner like a bullet
>would). One should be able to draw a photon-sized bullseye on the detector
>and hit it every time a single photon is shot through the double-slit
>apparatus. But can this be done?
>
>No. The single photon inteferes with itself and the location of the "single
>dot" it produces on the detector cannot be predicted. Probability rules.
>Where waves would reinforce were a stream of photons shot through
>simultaneously, one is more likely to find the strike-site of that single
>photon; and where waves would cancel out each other were a stream of photons
>shot through simultaneously, one is less likely to find the strike-site of
>that single photon.
>
>Certainty gives way to probability, as does determinism.
Chris
Probability and determinism, are, of course, compatible. Since we do not,
as far as I know, have any definite ideas as to the underlying causal
mechanisms that might determine the behavior of the particles at this level
of detail, out *lack* of knowledge and indeterminism look very similar. I
suspect that the determinism involved is something like a matter of phase
differences, so that two *seemingly* identical situations at this level
might differ in phase-relationships, and these differences could be crucial
to determining whether, for example, the spin of a particle is left rather
than right, or exactly where it seems to be at the time of collision. The
"jittering" of the "quantum foam" might be another determining factor to
consider.
Functionally, of course, for now, these kinds of determinism are the same
as indeterminism in that the inability to predict or measure with precision
is the same in either case.
>DNAunion
>The tunneling of particles through a barrier also takes advantage of
>probability (wave properties). In the Sun, even with the intense found found
>there, the energies that protons have is insufficient to overcome the
>electromagnetic replusion they have for one another: the energy barrier they
>have to cross in order to combine is too great. Yet protons DO
>collide/combine in the Sun - how is this possible? Because they have enough
>energy to make it part way up the energy barrier, and as they do, the
>probability of finding themselves on the other side of the barrier (because
>of their wave properties) increases, and a small percentage actually do cross
>the barrier (despite not having enough energy to do so). Again, one cannot
>say confidently whether or not two particular protons will combine -
>probability rules.
Chris
On this, I pretty much agree. I'm not saying that reality is *smooth* in
the old Newtonian sense. I'm merely saying that *all* of these phenomena,
and many more, are compatible with determinism (indeed, there may be a
single basic mechanism involved in these cases, though I won't go so far as
to predict that that will be found to be the case empirically). I
definitely agree that, from our vantage point of ignorance about "internal"
details, probability is the best we can do, and that reality, however it
turns out to do this, does in a way that yields probabilistic statistics at
the level of detail of observation that we have any way to perform, or
even, perhaps, conceive of, given our present level of knowledge and
understanding.
But, that's one reason I keep pushing for the deterministic view of this
aspect of physics: To promote research into questions that have been
somewhat off limits because of Bohr's success in turning a question of how
to find out something unknown into a claim that there is nothing to *be* known.
Obviously, for the same reasons we cannot disprove determinism in this
area, we also cannot prove determinism by empirical means. So, I'm not
claiming determinism on a purely scientific basis, but on the basis of
philosophical premises (i.e., that the physical universe is real, logically
(and therefore causally) consistent, etc.). Therefore, I don't offer the
above comments as strong positive support, but merely as defense of the
possibility.
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