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Generalised coherent states and the diagonal representation for operators

N. Mukunda·Arvind·S. Chaturvedi·R. Simon
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Abstract

We consider the problem of existence of the diagonal representation for operators in the space of a family of generalized coherent states associated with an unitary irreducible representation of a (compact) Lie group. We show that necessary and sufficient conditions for the possibility of such a representation can be obtained by combining Clebsch-Gordan theory and the reciprocity theorems associated with induced unitary group representation. Applications to several examples involving $SU(2),$ $SU(3),$ and the Heisenberg-Weyl group are presented, showing that there are simple examples of generalized coherent states which do not meet these conditions. Our results are relevant for phase-space description of quantum mechanics and quantum state reconstruction problems.

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N. Mukunda, Arvind, S. Chaturvedi, R. Simon. 2000-02-24. Generalised coherent states and the diagonal representation for operators. https://doi.org/10.1063/1.1559416

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