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Quasi-classical limit of KP hierarchy, W-symmetries and free fermions

Kanehisa Takasaki·Takashi Takebe
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Abstract

This paper deals with the dispersionless KP hierarchy from the point of view of quasi-classical limit. Its Lax formalism, W-infinity symmetries and general solutions are shown to be reproduced from their counterparts in the KP hierarchy in the limit of $\hbar \to 0$. Free fermions and bosonized vertex operators play a key role in the description of W-infinity symmetries and general solutions, which is technically very similar to a recent free fermion formalism of $c=1$ matrix models.

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Kanehisa Takasaki, Takashi Takebe. 1993-02-03. Quasi-classical limit of KP hierarchy, W-symmetries and free fermions. https://arxiv.org/abs/hep-th/9207081

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