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arXiv · 2507.23469

Exact quasi-periodic solutions to the MKdV equation

Julia Bernatska
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Abstract

In the present paper, a hierarchy of the mKdV equation is integrated by the methods of algebraic geometry. The mKdV hierarchy in question arises on coadjoint orbits in the loop algebra of $\mathfrak{sl}(2)$, and employs a family of hyperelliptic curves as spectral curves. A generic form of the finite-gap solution in any genus is obtained in terms of the $\wp$-functions, which generalize the Weierstrass $\wp$-function. Reality conditions for quasi-periodic wave solutions are completely specified. The obtained solutions are illustrated by plots in small genera.

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Julia Bernatska. 2025-07-31. Exact quasi-periodic solutions to the MKdV equation. https://arxiv.org/abs/2507.23469

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