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Contracting the Wigner-Kernel of a Spin to the Wigner-Kernel of a Particle

Jean-Pierre Amiet·Stefan Weigert
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Abstract

A general relation between the Moyal formalisms for a spin and a particle is established. Once the formalism has been set up for a spin, the phase-space description of a particle is obtained from the `contraction' of the group of rotations to the group of translations. This is shown by explicitly contracting a spin Wigner-kernel to the Wigner kernel of a particle. In fact, only one out of 2^{2s} different possible kernels for a spin shows this behaviour.

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Jean-Pierre Amiet, Stefan Weigert. 2000-04-13. Contracting the Wigner-Kernel of a Spin to the Wigner-Kernel of a Particle. https://doi.org/10.1103/physreva.63.012102

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