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arXiv · 2607.25596

Tau functions of the constrained matrix KP hierarchy

Xiaohan Fan·Jipeng Cheng·Jinbiao Wang
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Abstract

The constrained matrix KP hierarchy $(L^{k})_{<0}=\sum_{i=1}^{m}Q_{i}\partial^{-1}R_{i}^{\intercal}$ is investigated from the aspects of tau functions. Firstly, the matrix KP hierarchy is viewed as one special reduction of the multi-component KP hierarchy. Then bilinear equations of the constrained matrix KP hierarchy as the multi-component KP hierarchy are given in terms of tau functions. Finally based upon these results, the tau functions for the constrained matrix KP hierarchy are constructed by using the multi-component boson-fermion correspondence. Notice that the solutions of the constrained matrix KP hierarchy are derived without using quasi-determinants.

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Xiaohan Fan, Jipeng Cheng, Jinbiao Wang. 2026-07-28. Tau functions of the constrained matrix KP hierarchy. https://arxiv.org/abs/2607.25596

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