Greetings,
It is odd that most critiques of Complimentarity misunderstand it and, 'Shrodingers Cat,' is as
guilty as any other. Originally intended to reduce Complimentarity to absurdity it missed its mark
by such a margin that it is little wonder that Stephen Hawking says, "When I hear of Schrodingers
Cat, I reach for my gun."
JONATHAN:
""Schroedinger's Cat" is an illustration of the problem. A cat is dead or
alive in a soundproof, light-proof box. There is no way to determine
what is "true" without opening the box. Conventional philosophy says
that the cat is absolutely dead or absolutely alive, and the "truth"
will be established by opening the box. The whole point of the construct
is to illustrate an alternative Quantum Mechanics viewpoint, which says
that the cat is DISTRIBUTED between live and dead states according to
some function. The opening of the box "collapses" this function to give
a final live/dead outcome. In QM terms, this means that a "measurement"
on a particle actually changes its nature (collapses its wave function).
It is assumed that before measurement, the true nature of the particle
is described by a statistical distribution function."
We can see that the claim made for Complimentarity is that the measurement of a particle "actually
changes its nature," a mistake made also by Pirsig in his paper, 'Subjects, Objects, Data and
Values.'
PIRSIG:
"The most striking similarity between the Metaphysics of Quality and Complementarity is that this
Quality event corresponds to what Bohr means by "observation." When the Copenhagen Interpretation
"holds that the unmeasured atom is not real, that its attributes are created or realized in the act
of measurement," (Herbert xiii) it is saying something very close to the Metaphysics of Quality. The
observation creates the reality."
It is a shame that Pirsig relies upon secondary sources for this as it forms the cornerstone of his
thesis in that paper. Even Einstein made the same mistake, but fortunately was corrected by Bohr
himself. Einstein regarded it as absurd to believe that the moon exists only when we look at it to
which Bohr replied, "It is not that the moon DOES NOT exist when unobserved, but that we cannot KNOW
whether it, or some thoroughly unobserved moon of a remote and uninhabited planet, exists, until it
is observed."
PIRSIG:
"The explanation, I think, is that Bohr is prohibited from speaking about any external physical
reality ahead of the experiment. Before the experiment he must say there is nothing to know. . . . .
. . . . . . It is vital to Complementarity that there are no properties until after the
observation."
This is absolute nonsense. Bohr remains agnostic about what occurs below his threshold of
observability simply because he sees no point in conjecture. He never, ever, ever, suggested that
there are no properties until after the observation and, contrary to saying there IS NOTHING to
know, he says there is something but we cannot know what it is until we look. Look at what Bohr
writes: (my additions in brackets) "The wave function describing a particle constitutes a complete
description of that particle. Since the uncertainties (in our minds) expressed by the wave function
are not resolved until the particle is observed (once we look at it we can define it), the particles
can not be said ( = WE cannot say) to have any definite state (= WE cannot define) until it is
observed. The observer is implicated in what he or she observes but although he or she cannot
arbitrarily alter reality,(!!!) he or she can make a photon either a particle or a wave. (by
observing it in a certain context - in the same way that I can make a 3D cube on 2D paper appear as
if seen from above or below).
It is clear then that the, "Conceptually Unknown," has properties and is real despite our not being
able to define them or it. When we observe it we choose to define it in certain ways, just as I
choose to define this thing on my lap as a four legged animal, or as a cat, or as a pet, or as a
Burmese, depending upon the context in which I find myself. I haven't changed its nature in the
slightest and before I observed it, it was "Conceptually Unknown" to me - but a cat nonetheless.
Whatever the merits and demerits of Complementarity (and I make no judgement here), it doesn't say
what Schrodinger's Cat, Einstein or Pirsig claim it does and so can get along fine without having
the MoQ foisted onto it. Those who want to marry quantum physics with the MoQ will have to
reformulate this aspect completely.
KEN:
"if the Quantum theory were not
>predictable then our universe could not exist. Our coffee pours into the
>cup and tastes the same every morning. The toaster operates and the bread
>looks and reacts the same. In my mind this means that the Quantum world is
>producing similar results over time."
Quantum theory works below the level of predictability and this is not incompatible with the
existence of the universe. A good analogy is flipping a coin. If I flip one coin then you have only
a fifty/fifty chance of getting the answer right. This is the quantum level. If I flip 10 000 000
coins then for each one you only have a fifty/ fifty chance of getting it right, but in the larger
picture you can safely predict that 5 000 000 will be heads and 5 000 000 tails. The variation will
be statistically insignificant and so from small unpredictable events you build up a very stable
overall picture. Alternatively, take a good look at your bread. Choose one tiny spot and predict
whether it will go brown or stay white and you will as likely be wrong as right. But if you say that
the slice as a whole will go brown, you can safely bet you will be right. The point is that the
larger your system is, the more predictable it gets. There comes a point at the lower end where, for
all intents and purposes, it is completely unpredictable and a point at the upper end where it is
completely predictable.
To sum up, Schrodingers Cat will be whatever it is. If we want to find out whether it is dead or
alive we look, then define our observations according to our criteria of 'deadness' or 'aliveness.'
It is as simple as that.
Struan
------------------------------------------
Struan Hellier
< mailto:struan@shellier.freeserve.co.uk>
"All our best activities involve desires which are disciplined and
purified in the process."
(Iris Murdoch)
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