Subject: The quantised deus ex machina
Date: Mon, 18 Feb 2002 15:07:48 +0200 From: "Dimiter G. Chakalov" <dchakalov@surfeu.at> To: Gebhard Gruebl <gebhard.gruebl@uibk.ac.at> CC: oldstein@math.rutgers.edu, duerr@rz.mathematik.unimuenchen.de, tumulka@rz.mathematik.unimuenchen.de, zanghi@ge.infn.it, kmb@amath.unizh.ch, teufel@ma.tum.de, martin.daumer@imse.med.tumuenchen.de, bohmmech@rz.mathematik.unimuenchen.de, b.hiley@physics.bbk.ac.uk, stachel@buphy.bu.edu, j.fearns@ic.ac.uk, smoller@math.lsa.umich.edu, marco.matone@pd.infn.it BCC: [snip]
I like very much your remarks on Gleason's theorem [A.M. Gleason, J. Math. Mech. 6, 885 (1957)] and the measurement problem [Ref. 1]. May I ask two questions. If what reference frame, and with what physical clock would you measure the time evolution of Bohmian state: "It is assumed to be given by a Schrödinger equation for the wave function and by a time dependent tangent vector field v on the configuration space." [Ref. 1]? How would you approach the task of Lorentz invariant nonlocality? It seems to me that you would have to consider an individual quantum system. As Shelly Goldstein put it, the issue if extremely subtle, http://plato.stanford.edu/entries/qmbohm/#li Please also see [Refs. 2 and 3]. I hope to hear from you. I will also appreciate the feedback from all colleagues of yours reading these lines. Thank you very much in advance.
Regards, Dimiter G. Chakalov
References [Ref. 1] Gebhard Grübl, Klaus
Rheinberger. Time of Arrival from Bohmian Flow.
"The standard quantum physical interpretation of this body of mathematical facts leads to the following conclusion. It is inconsistent to suppose that the state of an individual quantum system is a deterministic state, i.e. determines values for all observables, and it is inconsistent to suppose that a density operator p only describes a mixture of such fictitious deterministic states. (It is generally held inconsistent to suppose that an individual particle has a specific position and a specific momentum and so on.) "From this conclusion then the notorious
quantum measurement problem follows: How can standard quantum theory represent
within its formalism the mere fact that individual closed systems do have
properties? (This surely is the case for systems comprising an observer
and not being in need of any sort of external observation inducing a state
reduction, the quantised deus ex machina.)
[Ref. 2] Joel Smoller. The Interaction
of Gravity with Other Fields.
"It follows that the Dirac particle *must* eventually
either disappear into the black hole, or escape to infinity; these are
the only possibilities."
[Ref. 3] Marco
Matone. Equivalence Postulate and Quantum Origin of Gravitation.
