Beyond Bell's Theorem is Leggett's nonlocal quantum surrealism

"Quantum mechanics fundamentally
concerns the way in which we observers connect to the universe
we observe. The theory implies that when we measure particles
and atoms, at least one of two long-held physical principles is
untenable: Distant events do not affect one other, and properties
we wish to observe exist before our measurements. One of
these, locality or realism, must be fundamentally incorrect.
... Now Zeilinger and his collaborators ...
In Vienna experiments are testing whether quantum
mechanics permits a fundamental physical reality. ...

(Nobel Laureate Tony) Leggett doesn’t believe quantum mechanics is correct, and
there are few places for a person of such disbelief to now turn.
But Leggett decided to find out what believing in quantum
mechanics might require. He worked out what would happen
if one took the idea of nonlocality in quantum mechanics seriously,
by allowing for just about any possible outside influences
on a detector set to register polarizations of light. Any unknown
event might change what is measured. The only assumption Leggett
made was that a natural form of realism hold true; photons should have measurable polarizations
that exist before they are measured. With this he laboriously derived a
new set of hidden variables theorems and inequalities as Bell once had.
But whereas Bell’s work could not distinguish between realism and locality,
Leggett’s did. The two could be tested. ...

The experiment wouldn’t be too difficult, but understanding it would. It took
them months to reach their tentative conclusion: If quantum
mechanics described the data, then the lights’ polarizations
didn’t exist before being measured. Realism in quantum
mechanics would be untenable ...

In the past decade or so, Zeilinger and his
many collaborators were the first to teleport light, use quantum
cryptography for a bank transaction (with optical fibers in the
sewers of Vienna), realize a one-way quantum computer, and
achieve entanglement over large distances through the air, first
across the Danube River and then between two of the Canary
Islands. Zeilinger’s work had also previously shown the greatest
distinction between quantum mechanics and local realism. ...

“Quantum mechanics is very fundamental, probably
even more fundamental than we appreciate,” he said, “But to
give up on realism altogether is certainly wrong. Going back to
Einstein, to give up realism about the moon, that’s ridiculous.
But on the quantum level we do have to give up realism.” ...

With eerie precision, the results of Gröblacher’s weekend
experiments had followed the curve predicted by quantum
mechanics. The data defied the predictions of Leggett’s model
by three orders of magnitude. Though they could never observe
it, the polarizations truly did not exist before being measured.
For so fundamental a result, Zeilinger and his group needed
to test quantum mechanics again ...

Leggett’s theory was more powerful than Bell’s  ...

In mid-2007 Fedrizzi found that the new realism model was
violated by 80 orders of magnitude;
the group was even more assured that
quantum mechanics was correct. ...

Last year Brukner and his student Johannes Kofler decided
to figure out why we do not perceive the quantum phenomena
around us. If quantum mechanics holds universally for atoms,
why do we not see directly its effects in bulk?

Most physicists believe that quantum effects get washed out
when there are a large number of particles around. The particles
are in constant interaction and their environment serves to “decohere”
the quantum world—eliminate superpositions—to create
the classical one we observe. Quantum mechanics has within it
its own demise, and the process is too rapid to ever see. Zeilinger’s
group, which has tested decoherence, does not believe there is a
fundamental limit on the size of an object to observe superposition.
Superpositions should exist even for objects we see, similar
to the infamous example of Schrödinger’s cat. In fact, Gröblacher
now spends his nights testing larger-scale quantum mechanics in
which a small mirror is humanely substituted for a cat.
Brukner and Kofler had a simple idea. They wanted to find
out what would happen if they assumed that a reality similar to
the one we experience is true—every large object has only one
value for each measurable property that does not change. In other
words, you know your couch is blue, and you don’t expect to be
able to alter it just by looking. This form of realism, “macrorealism,”
was first posited by Leggett in the 1980s.

Late last year Brukner and Kofler showed that it does not
matter how many particles are around, or how large an object
is, quantum mechanics always holds true. The reason we see
our world as we do is because of what we use to observe it.
The human body is a just barely adequate measuring device.
Quantum mechanics does not always wash itself out, but to
observe its effects for larger and larger objects we would need
more and more accurate measurement devices. We just do not
have the sensitivity to observe the quantum effects around us.
In essence we do create the classical world we perceive, and as
Brukner said, “There could be other classical worlds completely
different from ours.”

I am not sure if they are correct because of the emergence of
c-number order parameters that obey the nonlinear non-unitary
Landau-Ginzburg equation in ordinary space not the linear unitary
q-number Schrodinger equation in configuration space.



JOSHUA ROEBKE in May/June, 2008 http://www.SEEDMAGAZINE.COM Reality Tests