General Zakharov-Shabat equations without Lax operators
Exactly Solvable and Integrable Systems
2026-01-01 v1
Abstract
The operators in the Zakharov-Shabat equations of integrable hierarchies are usually defined from the Lax operators. In this article it is shown that the Zakharov-Shabat equations themselves recover the Lax operators under suitable change of independent variables in the case of the KP hierarchy and the modified KP hierarchy (in the matrix formulation).
Cite
@article{arxiv.2512.24216,
title = {General Zakharov-Shabat equations without Lax operators},
author = {Masatoshi Noumi and Takashi Takebe},
journal= {arXiv preprint arXiv:2512.24216},
year = {2026}
}
Comments
27 pages; revised (corrected) version of the second author's article in 1992