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arXiv · 2007.10187

Transition probabilities and transition rates in discrete phase space

William F. Braasch Jr.·William K. Wootters
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Abstract

The evolution of the discrete Wigner function is formally similar to a probabilistic process, but the transition probabilities, like the discrete Wigner function itself, can be negative. We investigate these transition probabilities, as well as the transition rates for a continuous process, aiming particularly to give simple criteria for deciding when a set of such quantities corresponds to a legitimate quantum process. We also show how the transition rates for any Hamiltonian evolution can be worked out by expanding the Hamiltonian as a linear combination of displacement operators in the discrete phase space.

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William F. Braasch Jr., William K. Wootters. 2020-10-12. Transition probabilities and transition rates in discrete phase space. https://doi.org/10.1103/physreva.102.052204

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