Hi Brent,
On 8/4/2011 4:38 PM, meekerdb wrote:
On 8/4/2011 12:10 PM, Stephen P. King wrote:
Hi Brent,
On 8/4/2011 1:44 PM, meekerdb wrote:
On 8/4/2011 9:41 AM, David Nyman wrote:
Hi Stephen
Thanks for the link - very enjoyable talk. As far as I could follow
it, he seemed to be saying that the differentiation of decoherent
"worlds" is in the final analysis a "psychological" matter - i.e. that
quasi-classical "reality", as ordinarily experienced, is consequent on
the selection of particular "best-fit" or "most fruitful"
interpretations of functional or structural features of the underlying
micro-physical state-of-affairs.
I don't see how life (including us) could exist except at a
quasi-classical level. Evolution needs reliable replication to work
with. Given that we evolved as quasi-classical beings, it follows
that our perception, psychology, and interaction with the world must
be quasi-classical.
Brent
Exactly what does the 'quasi-classical" property imply and what
does it bring to the table that is not in the quantum realm? Is it
persistence of structure? How does the unitary evolution of the wave
function not provide that?
It doesn't. Although decoherence theory is suggestive; it has not yet
been able to uniquely define "quasi-classical" within the framework of
QM without additional assumptions about pointer bases.
Again, what is the motivation of the quasi-classical approach?
More simple calculations? More intuitive models? I am asking about the
motivation to maintain a paradigm that has long lapsed into
obsolescence! The universe is not a giant clock work of isolatable and
separable parts as the scientists of the 18th and 19th century believed.
We have sufficient evidence to see this clearly, so why the romantic
attachment with this vision?
The assumptions about pointer bases is a throwback to Copenhagen,
where Borh, that great champion of QM desperately tried to get the
emerging experimental evidence to get along with the classical vision.
Few people still how up the Copenhagen interpretation as viable, with
its strange duality of classical measuring devices interacting with
quantum systems. Most people have adopted the Everetian vision of a
purely quantum universe, and yet that pesky basis problem persists! What
I am investigating is an attempt to solve that problem by considering
how the interactions between many systems tends to induce global
behaviors that are selective, selective in the same sense as what we
need to solve the basis problem.
Consider what happens when a large number of people communicate
with each other. Even if they start off speaking their own unique
language eventually, because of the way that communications in the real
world occurs, there will emerge a single language that prodominates. In
a similar way, I believe that a basis set emerges out of the
interactions between a large number of QM systems, a basis that
represents the maximally consistent set of observables for that
collection. This is a very crude sketch of the idea, but to explore it I
must jettison all of the classical ideas that so far have been poisoning
the well of thought on this problem.
In fact, the quantum realm seems to even be over-determinative in the
sense that no only is one 'actual' real state of affairs of a world
non-contradictorily exists in the amplitudes of the wave function but
all possible versions of it.
A popular myth. QM does not provide that "everything happens". For
example eigenstates of an operator remain eigenstates in the unitary
evolution.
Popular and mythological to whom? How does the persistence of
eigenstates under unitary evolution contradict what I wrote? Is it
incorrectly claimed that a quantum state is equivalent to *all possible
statements" that can be made of a system?
While it is true that we seem to observe only one Boolean logic
representable slice of the totality of what is coded in the
amplitudes, it can easily be shown
It isn't "shown" at all. It's hypothesized in one model.
Which model and what are the alternatives?
that this is just something like one subset of the set of all of the
Boolean representable 'possible worlds' that we see coded in the
amplitudes.
I simply do not comprehend this emotional clinging to a classical
vision of the world; especially given the fact that it is
demonstrably false! It seems to me that your argumentation is just an
attempt to preserve your apparent belief in naive realism.
It seems to me that your reification of the wave function is an over
reaching extension of what we know from our classical observation
driven by a distaste for randomness.
Is it that I have a distaste for randomness or is it that you have
an irrational affection for randomness? What does randomness give you
that you cannot live without?
Onward!
Stephen
--
You received this message because you are subscribed to the Google Groups
"Everything List" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/everything-list?hl=en.
