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arXiv · 1208.1374

Tau function of the CKP hierarchy and non-linearizable Virasoro symmetries

Liang Chang·Chao-Zhong Wu
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Abstract

We introduce a single tau function that represents the CKP hierarchy into a generalized Hirota "bilinear" equation. The actions on the tau function by additional symmetries for the hierarchy are calculated, which involve strictly more than a central extension of the $w^C_\infty$-algebra. As an application, for Drinfeld-Sokolov hierarchies of type C that are equivalent to certain reductions of the CKP hierarchy, their Virasoro symmetries are proved to be non-linearizable when acting on the tau function.

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Liang Chang, Chao-Zhong Wu. 2013-08-07. Tau function of the CKP hierarchy and non-linearizable Virasoro symmetries. https://doi.org/10.1088/0951-7715%2F26%2F9%2F2577

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