Regarding my earlier post on randomness, I received a fair amount of private
mail in response, as seems to be the pattern nowadays. Nonetheless, let me
respond to just this one publicly, simply because I consider the questions
that were asked important:

> I have always understood that a radioactive decay was an example of a
>  truly and totally random event; one can know that a certain number of
>  events, give or take a few, will occur in a given time, but which
>  particular atoms will choose to decay is unknown, and indeed,
>  unknowable.
>
>  Who thinks otherwise, and where do they write on this topic?

At its core, quantum mechanics is completely deterministic -- until it gets
to the point of a "measurement" (and even then, the definition of
"measurement" is only vaguely defined). But it is a this point that an
indeterminate "collapse" of the wave function is required. This is called the
"Copenhagen Interpretation" of quantum mechanics, and although this is the
interpretation that makes most of the graduate textbooks on the subject, it
is far from universally accepted.

As to who objects to this interpretation, Einstein is always the most
quotable, with his most famous quote being his December 4, 1926 letter to Max
Born:

"Quantum Mechanics demands serious attention. But an inner voice tells me
that this is not the true Jacob. The theory accomplishes a lot, but it does
not bring us closer to the secrets of the Old One. In any case, I am
convinced that He does not play dice."

A clear and concise outline of the "Copenhagen Interpretation" appears
on-line at:

     http://www.benbest.com/science/quantum.html

and a similarly clear outline of the "measurement problem" appears on-line at:

     http://plato.stanford.edu/entries/qt-measurement/

Ilya Prigogine, one of my favorite physicists, is actually a chemist (who
received the Nobel Prize in Chemistry for his work in non-equilibrium
thermodynamics). He wrote this a few years ago, in 1993:

" ... Nevertheless 60 years after the formulation of quantum mechanics there
is still vehement discussion over its interpretation and range of
application. That is something unique in the history of science. Obviously,
in spite of all its sucess, it causes a certain uneasiness in most
physicists. Richard Feynman even actually said that nobody 'understands' the
Quantum Theory " [Ilya Prigogine , Das Paradox der Zeit - Zeit , Chaos und
Quanten ( English title : Time , Chaos and the Quantum . Towards the the
Resolution of the Time Paradox ), p. 169]




>  It sounds like you too, agree, and lean towards us being in a
>  deterministic, if no longer simply Newtonian, universe.

I personally have no opinion on this subject. I could live with the universe
being either way, not that I have a great deal to say about the matter :-).
However my predilicition is to believe that what we call "randomness" is
merely "unknowiness".

You don't have to resort to quantum mechanics to get highly unpredictable
results. The Greeks created the words "chaos" and "cosmos" to represent the
two antitheses. Chaos is complete disorder. Cosmos is complete order.

A few years ago, "chaos theory" became an extremely popular subject, with all
sorts of popular science books written about the material. But this "chaos"
was not the chaos of the Greeks. The chaotic reactions that were under study
(e.g., the rivulets of water on a car's windshield) are completely
deterministic and predictable, if you know with great precision the intitial
conditions with they are launched. In essence, these processes are no
different than the behavior of a pseudo-random number generator. If you could
accurately specify the seed value, the resulting reaction chain would be the
same every time.

Billiards is presumed to be governed a completely deterministic, Newtonian
physics, capable of being completely specified at any point in time. However,
whenever I play (which is once per decade), I tend to be completely surprised
by the outcome of my shots. In many-body situations, small errors can
aggregate themselves into wildly different outcomes.

It is my lack of foreknowledge that causes my surprise and the general
"randomness" of the response. On a quantum mechanical scale, it is entirely
possible that the same situation governs. In either circumstance, if I could,
through an immense amount of wasted time, learn to describe the initial, a
priori states of billiards with greater and greater precision, the range of
variation in the positions and momentums of the resulting various component
pieces would be more and more constrained, until possibly, at that point of
my obtaining perfect knowledge, all "randomness" would disappear.

The notion of "unknowable knowledge" lies at the heart of the measurement
problem in quantum mechanics. If that isn't true, then God may yet not play
dice with the universe. The person most recently associated with this
viewpoint is David Bohm, and his cause has been taken up of late by Jon Bell.

A 1994 Scientific American article about Bohm's causal quantum mechanical
interpretations is "David Z. Albert, Bohm's Alternative to Quantum Mechanics,
Scientific American, Volume 270, Number 5, pp. 32-39 (May 1994)."




>  I have philosophical problems with that; how could there be 'free will'
>  in a determined universe?
>
>  And I think one of the few things that believers and atheists alike
>  agree on is the necessity for free will.
>
>  Not, of course, that the objectivity of science should be subsumed to my
>  conceptual difficulties.... :-)

Somehow all of this material readily slips over into philosophy, but to
attempt to derive any sort of moral or religious view from such a shaky
foundation will inevitably, in a hundred years' time, appear to be at best
naive, and at worst foolish. When we finally understand all of this, the
philosophical questions surrounding quantum mechanics will seem as odd as the
anthropologist's question a few years back to a newly discovered stone age
tribe, "Do you talk to rocks?" The reply was, "No. Do you?!"

Nonetheless, imposing philosophy on all of this somehow seems inescapable,
even for the participants themselves. Heisenberg toured Europe lecturing on
the knowability of "truth" in the 1930's, and David Bohm was no different. It
may be that the current mysteriousness of quantum mechanics invokes a sense
of religious mysticism, but that sense of mysteriousness is almost certain to
be peeled back and made transparent sometime this century, and much of the
philosophical musings are certain to die away with that understanding.

Wirt Atmar

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