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Quantum Equilibrium and the Role of Operators as Observables in Quantum Theory

Detlef Dürr·Sheldon Goldstein·Nino Zangh\`ı
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Abstract

Bohmian mechnaics is the most naively obvious embedding imaginable of Schrödingers's equation into a completely coherent physical theory. It describes a world in which particles move in a highly non-Newtonian sort of way, one which may at first appear to have little to do with the spectrum of predictions of quantum mechanics. It turns out, however, that as a consequence of the defining dynamical equations of Bohmian mechanics, when a system has wave function $ψ$ its configuration is typically random, with probability density $ρ$ given by $|ψ|^2$, the quantum equilibrium distribution. It also turns out that the entire quantum formalism, operators as observables and all the rest, naturally emerges in Bohmian mechanics from the analysis of ``measurements.'' This analysis reveals the status of operators as observables in the description of quantum phenomena, and facilitates a clear view of the range of applicability of the usual quantum mechanical formulas.

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Detlef Dürr, Sheldon Goldstein, Nino Zangh\`ı. 2003-08-06. Quantum Equilibrium and the Role of Operators as Observables in Quantum Theory. https://doi.org/10.1023/b%3Ajoss.0000037234.80916.d0

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