Breakdown of the coherent state path integral: two simple examples

Justin H. Wilson; Victor Galitski

doi:10.1103/physrevlett.106.110401

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arXiv · 1012.1328

Breakdown of the coherent state path integral: two simple examples

Justin H. Wilson·Victor Galitski

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Abstract

We show how the time-continuous coherent state path integral breaks down for both the single-site Bose-Hubbard model and the spin path integral. Specifically, when the Hamiltonian is quadratic in a generator of the algebra used to construct coherent states, the path integral fails to produce correct results following from an operator approach. As suggested by previous authors, we note that the problems do not arise in the time-discretized version of the path integral.

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Justin H. Wilson, Victor Galitski. 2010-12-06. Breakdown of the coherent state path integral: two simple examples. https://doi.org/10.1103/physrevlett.106.110401

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