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arXiv · 0710.3315

Can the Quantum Measurement Problem be resolved within the framework of Schroedinger Dynamics and Quantum Probability?

Geoffrey Sewell
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Abstract

We provide an affirmative answer to the question posed in the title. Our argument is based on a treatment of the Schroedinger dynamics of the composite of a quantum microsystem, S, and a macroscopic measuring apparatus, I, consisting of N interacting particles. The pointer positions of this apparatus are represented by orthogonal subspaces of its representative Hilbert space that are simultaneous eigenspaces of coarse-grained macroscopic observables. By taking explicit account of their macroscopicality via a large deviation principle, we prove that, for a suitably designed apparatus I, the evolution of the composite (S+I) leads both to the reduction of the wave packet of S and to a one-to-one correspondence between the resultant state of this microsystem and the pointer position of I, up to utterly negligible corrections that decrease exponentially with N.

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Geoffrey Sewell. 2007-10-17. Can the Quantum Measurement Problem be resolved within the framework of Schroedinger Dynamics and Quantum Probability?. https://doi.org/10.1063/1.2827306

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