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Real-normalized Whitham hierarchies and the WDVV equations

Anton Dzhamay
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Abstract

In this paper we present a construction of a new class of explicit solutions to the WDVV (or associativity) equations. Our construction is based on a relationship between the WDVV equations and Whitham (or modulation) equations. Whitham equations appear in the perturbation theory of exact algebro-geometric solutions of soliton equations and are defined on the moduli space of algebraic curves with some extra algebro-geometric data. It was first observed by Krichever that for curves of genus zero the tau-function of a ``universal'' Whitham hierarchy gives a solution to the WDVV equations. This construction was later extended by Dubrovin and Krichever to algebraic curves of higher genus. Such extension depends on the choice of a normalization for the corresponding Whitham differentials. Traditionally only complex normalization (or the normalization w.r.t. a-cycles) was considered. In this paper we generalize the above construction to the real-normalized case.

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Anton Dzhamay. 2000-03-05. Real-normalized Whitham hierarchies and the WDVV equations. https://arxiv.org/abs/hep-th/0003034

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