Journal of Physics A Mathematical and General

Time observables with projective covariance

Nicola Pinamonti, M. Toller

Published Apr 8, 2002• 1 citation

Abstract

We study the positive-operator-valued measures (POVMs) on the projective real line covariant with respect to the projective group. We interpret the projective line as a compactified time axis and we assume that the energy is a positive operator. This formalism may describe a time-of-arrival observable for a free particle covariant with respect to linear canonical transformations. The problem is similar to the more complicated and physically more relevant problem of finding the POVMs on the compactified Minkowski space-time covariant with respect to the conformal group.

DOI: 10.1088/0305-4470/35/15/313

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