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arXiv · 2008.13123

Explicit closed algebraic formulas for Orlov-Scherbin $n$-point functions

Boris Bychkov·Petr Dunin-Barkowski·Maxim Kazarian·Sergey Shadrin
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Abstract

We derive a new explicit formula in terms of sums over graphs for the $n$-point correlation functions of general formal weighted double Hurwitz numbers coming from the Kadomtsev-Petviashvili tau functions of hypergeometric type (also known as Orlov-Scherbin partition functions). Notably, we use the change of variables suggested by the associated spectral curve, and our formula turns out to be a polynomial expression in a certain small set of formal functions defined on the spectral curve.

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Boris Bychkov, Petr Dunin-Barkowski, Maxim Kazarian, Sergey Shadrin. 2021-06-30. Explicit closed algebraic formulas for Orlov-Scherbin $n$-point functions. https://doi.org/10.5802/jep.202

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