| "Tolerates" is indeed a better choice of words than "postulates."
Quantum mechanics gives its answers in terms of probabilities, for
the most part. This results in things like the famous Heisenberg
Uncertainty Principle, which, in one form, states that
dp dx = h
where dp is the uncertainty, the possible spread, in the value of
a particle's momentum, dx is the uncertainty in position, and
h is Planck's constant, a fixed number. Also, the = sign should
be "greater than or equal to," but that is beyond my keyboard.
The question then arises, What is uncertain in the Uncertainty
Principle? Is it just a description of our own ignorance, a limit
on what we can find out, set by nature? Or is matter itself uncertain,
lacking in a definite value?
The questions came to a crescendo around 1930, with Niels Bohr leading
the view that the world is uncertain and Albert Einstein maintaining
that it was just us. Bohr more or less won, or at least had the
last word in the debates, but nothing has been settled. And now
these questions are coming up again.
In the Einsteinian view, the world is single and definite, just
as common sense would have it. This implies that quantum mechanics
is not a complete description of the world, since it describes things
vaguely, so to speak. (Not that it isn't useful. All solid state
electronics, for instance, is applied quantum mechanics, as is most
modern chemistry.) However, QM is a very good description as far
as it goes, and that means that whatever the truth behind QM is,
it must fall within the limits already set by QM. To do so, it
must involve physical properties not constrained by space and time,
allowing, for instance, information to move faster than light or
backwards in time. This makes some folks very uncomfortable.
In Bohr's view, the world doesn't HAVE a definite physical state
until you look at it. The act of observation forces the world to
"make up its mind," so to speak. Einstein once bluntly asked Bohr,
"Do you think the moon is there when no one is looking at it?"
I don't know what Bohr replied, but in terms of his theory, the
answer would be something like: "No, it isn't, there's just a very
good chance that the next time someone looks for the moon, they'll
find it there. What they'll find will be one out of a spectrum
of possible moons, selected at random."
A man named Everett went on to develop Bohr's theory and suggested
that each of those possible moons is real. Every time there is
more than one physical possibility, all become real in a different
parallel world. I think this is the "many realities" idea you refer
to. No one has exactly disproved this, but it has some mathematical
problems with it, and it is more often used by science fiction authors
than by physicists.
Personally, I take Einstein's side. The non-local physics doesn't
bother me, while Bohr's solipcism does. But it's a matter of personal
taste or metaphysics, not science. Not yet, anyway. Whichever
side turns out to be right, the world must be a very odd place.
Earl Wajenberg
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| Re .1:
The Bohr view rather implies rthat everything's more or less formless
until there's an intelligence to appreciate it, one would think.
Something interesting: While the ancient Egyptian mythologies are
often at variance or mutuallty exclusive, one story of the creation,
centering on Khephera, the scarab-god, was that he created the world
by sending his thoughts rippling across _the surface_ of Chaos.
The Chaos, therefore, still was there, just covered by a thin veneer
of "reality."
Nothing much, but an interesting fable in this context...
Steve Kallis, Jr.
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|
Just discovered this note. I think another way to approach the original
question is not to view quantum mechanics from Bohr's perspective,
but to see it more in the representation of P.A.M. Dirac. The given
state of any mass (or energy packet, if you will) can be represented
by a state vector (the WAVE FUNCTION of the Shroedinger representation).
The state vector exists mathematically in what is known as Hilbert
space (sort of like 3D space,but much different). Hilbert space
is characterized as being infinitly dimensional. Like any other
vector, the state vector also has component vectors that 'combine'
or form a basis for the state vector. It's pretty much the same
idea as fourrier analysis, where one can form any given function
by combining the correct proportions of fundemental functions -
'waves' -. Like a piano string vibrating at a given frequency, is
made up of many fundenmental frequencies or harmonics, so to the
wave function or state vector of QM is composed of many "harmonics",
except in QM there is an infinite number of components or 'harmonics',
which is the reason the state vector is represented in hilbert space.
Now (time to breath), imagine your reality as the state vector.
This would imply that your reality is really nothing but the 'relative
proprortions' of the infinite number of all the possible realities
that exist.
just a little pet theory of mine ( please excuse any inaccuracies,
it's literaly been 10 years since I've studied this stuff in graduate
school)
happy realities,
peter
peter
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