The discussion centers on the calculation of entanglement within Bohm's theory, particularly in relation to hidden variables and how it compares to standard quantum theory. Participants explore the implications of the global wave function in Bohm's framework, the necessity of calculating it, and the potential for obtaining results consistent with standard quantum mechanics.
Participants express differing views on the relationship between Bohm's theory and standard quantum theory, with some asserting that Bohm's theory reproduces standard results while others challenge this assertion. The discussion remains unresolved regarding the implications of hidden variables and the validity of the general theorem mentioned.
Limitations include the dependence on specific definitions of entanglement and the global wave function, as well as unresolved mathematical steps regarding the calculations in Bohm's theory.
Demystifier said:And all this does not depend at all on hidden variables.
Demystifier said:SQM - wf Collapse - Non Linear.
RUTA said:At least that's what they told me here at the Hiley Symposium this week.
No, what I said IN THE POST ABOVE, does not depend on superluminal information exchange.RUTA said:But it does depend on superluminal information exchange, even in its Lorentz invariant manifestations. At least that's what they told me here at the Hiley Symposium this week.
SQM - wf collapse, but no modelyoda jedi said:SQM - wf Collapse.
which one ? specific model please...
Demystifier said:SQM - wf collapse, but no model
GRW, Penrose (or some other) specific model - no SQM
By SQM, I meant SQM with collapse, but without mathematical description of collapse in terms of a precise model. Instead, collapse is introduced as a vague postulate. Something like: "When a measurement is performed, the wave function collapses to an eigenstate of the measured observable."yoda jedi said:you mean SQM without collapse ?
Demystifier said:By SQM, I meant SQM with collapse, but without mathematical description of collapse in terms of a precise model. Instead, collapse is introduced as a vague postulate. Something like: "When a measurement is performed, the wave function collapses to an eigenstate of the measured observable."
The measurement I am talking here about is known also under the name non-demolition measurement:Demystifier said:Fine, it works for one specific choice of the measured observable A only.
But then for another choice of the observable B (B not equal to A), I choose ANOTHER basis \varphi_b(x), so instead of (40) now I can write
\psi(x,t) = \sum_b d_b(t) \varphi_b(x)
To measure B (rather than A) I have to apply a different interaction, so now (42) will no longer be true. Instead, with that different interaction, instead of (42) I will have
\Phi(x,z,t) = \sum_b d_b(t) \varphi_b(x) \xi_b(z)
This is different from (42). Yet, it has the same FORM as (42).
The physical point is that there is no measurement without interaction, and each kind of measurement requires a different kind of interaction. Consequently, each kind of measurement will lead to a different wave function. Yet, as long as each of these measuremts is "ideal", the wave function after the interaction always takes the FORM (42).
And all this does not depend at all on hidden variables.