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On Hubbard-Stratonovich Transformations over Hyperbolic Domains

Yan V. Fyodorov
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Abstract

We discuss and prove validity of the Hubbard-Stratonovich (HS) identities over hyperbolic domains which are used frequently in the studies on disordered systems and random matrices. We also introduce a counterpart of the HS identity arising in disordered systems with "chiral" symmetry. Apart from this we outline a way of deriving the nonlinear $σ$-model from the gauge-invariant Wegner $k-$orbital model avoiding the use of the HS transformations.

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BibTeXRIS

Yan V. Fyodorov. 2004-10-11. On Hubbard-Stratonovich Transformations over Hyperbolic Domains. https://doi.org/10.1088/0953-8984%2F17%2F20%2F018

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