Beltrami equation and τ - function for dispersionless hierarchies
نویسندگان
چکیده
It is proved that the action for nonlinear Beltrami equation (quasi-classical ¯ ∂-problem) evaluated on its solution gives a τ-function for dis-persionless KP hierarchy. Infinitesimal transformations of τ-function corresponding to variations of ¯ ∂-data are found. Determinant equations for the function generating these transformations are derived. They represent a dispersionless analogue of singular manifold (Schwar-zian) KP equations. Dispersionless 2DTL hierarchy is also considered.
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