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Ilja Schmelzer
Jan29-06, 06:00 AM
"Ralph Hartley" <hartley@aic.nrl.navy.mil> schrieb im Newsbeitrag
news:43D7FD27.6020706@aic.nrl.navy.mil...

> Ilja Schmelzer wrote:

> > "Hendrik van Hees" <hees@comp.tamu.edu> schrieb

> >>... one should not interpret more into the theory than there is

> >>contained in it.

> >

> > The minimal interpretation is, in some sense, not an interpretation

> > but a refusal to interprete.

>

> A *justified* refusal to interpret. Because all other interpretations

> interpret more into the theory than is contained in it.

In a situation where different theories are undistinguishable by

observation, they are considered to be equivalent and named

interpretations of the same theory. Then it is also reasonable to

define a "minimal interpretation" which contains only those

parts shared by all theories.

Then, by construction, all other interpretations interpret more

into "the theory" than is contained in it.

> > ... The minimal interpretation is not in conflict with other,

> > non-minimal interpretations, but defines the common part of various

> > interpretations. In all questions where different interpretations

> > give different answers the minimal interpretation remains silent.

> Just so. But that's only *one* of it's good properties.

> Another it that it *is* complete, in the sense that it answers all

> questions that are experimentally testable.

Also a consequence of the construction principle.

> No one ever promised you answers to any other questions.

> No one promised that any others even *have* answers.

So what? No one promised me anything. No one promised

me that there exists a unified theory. No one promised me

I have a chance to find it. Nonetheless I try to find it.

> Other interpretations are useful aids to thought, for example they

> make the causal properties easier to see, but they all contain

> something unneeded.

Unneeded? Depends on what you want. If you want to know some

scattering amplitudes of some very unstable particles, these

interpretations contain something unneeded. But if you simply

want to understand how the univers works, and experimental

tests are only a tool to reject wrong theories?

> Suppose someone suggested a bet on what the "correct" interpretation

> is. How would you *settle* such a bet?

There are lots of different criteria, like simplicity, beauty.

> Even if there were a "correct"

> interpretation, what would it be good for?

It helps me to understand how the universe works. I'm

just curious how this funny thing named universe works.

> It would not predict the results of even one more experiment.

I'm not really interested in scattering amplitudes themself.

For me they are only a tool to recognize some wrong theories

as wrong.

> The answer to the question "what is real" does not have any impact on

> our observable universe. I would be willing to let that one slide,

> except for:

>

> > You cannot assume the nonexistence of a preferred frame. Because no

> > realistic description of the world is possible without some real

> > effects happening FTL.

>

> Therefore *all* realistic (in your narrow sense) theories contain

> something with no impact on our universe.

No. The impact can be seen (the CMBR). I believe that the

theory we need to understand the initial conditions of our universe

- a quantum TOE - will not have relativistic symmetry.

> In a broader sense, "many worlds", if taken literally (which I do

> *not* normally recommend), is completely realistic.

I see no reason to weaken the notion of realism used by EPR

and Bell. In this sense, MWI is not a realistic interpretation.

I follow Bell who has characterized it as "extravagant, and

above all extravagantly vague" which he "could almost

dismiss as silly".

> If it is correct, ...

> ...We don't remember things happening that way,

> but we wouldn't be expected to. In each world we remember only one

> particular outcome, and wonder what determined it, or why our

> "consciousness", whatever that is, ended up in that particular world.

I wonder only what distinguishes this sort of "explanation" from

"Gods Will is unexplainable".

> Science consists of finding realistic (in the broad sense), local

> deterministic, theories. Many worlds has those properties, and BM does

> not, so BM should not even be considered.

According to this methodology, Newtonian gravity should not have been

considered, for the same reason you propose not to consider BM:

nonlocality. Fortunately, Newton's decision was different.

> Do I really think that? No. But if I did, I would be just as consistent

> in using realistic language, and in calling myself a realist, as you are.

There is a difference. My notion of realism is well-defined, MWI is instead

vague. It is hard to prove inconsistence if everything is vague.

> I don't actually prefer any interpretation, except as aids to intuition.

> Questions that cannot be answered *should* not be answered.

"cannot be answered" is very different from "there are many possible

answers, and it is hard to say which answer is preferable".

Ilja