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Dispersionless Hirota equations of two-component BKP hierarchy

Kanehisa Takasaki
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Abstract

The BKP hierarchy has a two-component analogue (the 2-BKP hierarchy). Dispersionless limit of this multi-component hierarchy is considered on the level of the $τ$-function. The so called dispersionless Hirota equations are obtained from the Hirota equations of the $τ$-function. These dispersionless Hirota equations turn out to be equivalent to a system of Hamilton-Jacobi equations. Other relevant equations, in particular, dispersionless Lax equations, can be derived from these fundamental equations. For comparison, another approach based on auxiliary linear equations is also presented.

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Kanehisa Takasaki. 2006-06-08. Dispersionless Hirota equations of two-component BKP hierarchy. https://arxiv.org/abs/nlin/0604003

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