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arXiv · 2201.11020

The matrix-resolvent method to tau-functions for the nonlinear Schr\"odinger hierarchy

Ang Fu·Di Yang
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Abstract

We extend the matrix-resolvent method of computing logarithmic derivatives of tau-functions to the nonlinear Schr\"odinger (NLS) hierarchy. Based on this method we give a detailed proof of a theorem of Carlet, Dubrovin and Zhang regarding the relationship between the Toda lattice hierarchy and the NLS hierarchy. As an application, we give an improvement of an algorithm of computing correlators in hermitian matrix models.

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Ang Fu, Di Yang. 2022-01-26. The matrix-resolvent method to tau-functions for the nonlinear Schr\"odinger hierarchy. https://arxiv.org/abs/2201.11020

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