English

From Toda Hierarchy to KP Hierarchy

Exactly Solvable and Integrable Systems 2025-08-12 v3 Mathematical Physics Algebraic Geometry math.MP

Abstract

Using the matrix-resolvent method and a formula of the second-named author on the nn-point function for a KP tau-function, we show that the tau-function of an arbitrary solution to the Toda lattice hierarchy is a KP tau-function. We then generalize this result to tau-functions for the extended Toda hierarchy (ETH) by developing the matrix-resolvent method for the ETH. As an example the partition function of Gromov-Witten invariants of the complex projective line is a KP tau-function, and an application on irreducible representations of the symmetric group is obtained.

Keywords

Cite

@article{arxiv.2311.06506,
  title  = {From Toda Hierarchy to KP Hierarchy},
  author = {Di Yang and Jian Zhou},
  journal= {arXiv preprint arXiv:2311.06506},
  year   = {2025}
}