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strangerep

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This is a continuation of discussions from another thread:

https://www.physicsforums.com/showthread.php?t=490677&page=2

I believe it deserves its own thread instead of hijacking the other one.

"Ref 3" in what follows is this paper:

L.E. Ballentine, "The Statistical Interpretation of QM",

Rev Mod Phys, vol 42, no 4, 1970, p358.

The context of Ballentine's remark on p379 is that "it is possible to

extend the formalism of QM by the introduction of

This demonstrates that there is no conflict with quantum theory in

thinking of a particle as having definite (but, in general, unknown)

values of both position and momentum."

It's also essential to understand Ballentine's points about the

distinction between state preparation and measurement. See p365,366.

"The statistical dispersion principle which follows from QM formalism

is a statement about the minimum dispersion possible in any state

preparation. This is distinct from errors of simultaneous measurements

of q and p one

in the context of Ballentine's discussion of his Fig 3.

theory of QG will not contradict experimental results. :-)

But you're kinda putting words in my mouth. I don't think the statistical

interpretation is "vague".

https://www.physicsforums.com/showthread.php?t=490677&page=2

I believe it deserves its own thread instead of hijacking the other one.

"Ref 3" in what follows is this paper:

L.E. Ballentine, "The Statistical Interpretation of QM",

Rev Mod Phys, vol 42, no 4, 1970, p358.

It's easy to get a misleading impression by quoting bits out of context.[...] on p. 361 of ref. [3], [Ballentine] says, the Statistical

Interpretation considers a particle to always be at some position in

space, each position being realised with relative frequency

[itex]|\psi(\mathbf{r})|^2[/itex] in an ensemble of similarly prepared

experiments. Later [3, p. 379] he states, there is no conflict with

quantum theory in thinking of a particle as having definite (but, in

general, unknown) values of both position and momentum.

The context of Ballentine's remark on p379 is that "it is possible to

extend the formalism of QM by the introduction of

*joint probability*

distributionsfor position and momentum (section 5 of his paper).distributions

This demonstrates that there is no conflict with quantum theory in

thinking of a particle as having definite (but, in general, unknown)

values of both position and momentum."

It's also essential to understand Ballentine's points about the

distinction between state preparation and measurement. See p365,366.

"The statistical dispersion principle which follows from QM formalism

is a statement about the minimum dispersion possible in any state

preparation. This is distinct from errors of simultaneous measurements

of q and p one

*one*system." This argument should be understoodin the context of Ballentine's discussion of his Fig 3.

If "dull" means no accompanying fairy stories, then I'm ok with that. :-)I'm not sure how Ballentine's thinking has

developed with the huge number of sophisticated experimental results in

the last 20 years, but perhaps it is possible to make the ensemble

interpretation consistent with everything so far discovered, since it

doesn't say much beyond the basic mathematical model of QM. But it's

terribly dull ;-)

The only thing I can say with confidence about this is that the "correct"unusualname said:Do you really think the correct (and simplest) theory of QG will still rely on

a vague "interpretation"?

theory of QG will not contradict experimental results. :-)

But you're kinda putting words in my mouth. I don't think the statistical

interpretation is "vague".

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