English

Weighted Hurwitz numbers, $\tau$-functions and matrix integrals

Mathematical Physics 2021-11-30 v1 Combinatorics math.MP Exactly Solvable and Integrable Systems

Abstract

The basis elements spanning the Sato Grassmannian element corresponding to the KP τ\tau-function that serves as generating function for rationally weighted Hurwitz numbers are shown to be Meijer GG-functions. Using their Mellin-Barnes integral representation the τ\tau-function, evaluated at the trace invariants of an externally coupled matrix, is expressed as a matrix integral. Using the Mellin-Barnes integral transform of an infinite product of Γ\Gamma functions, a similar matrix integral representation is given for the KP τ\tau-function that serves as generating function for quantum weighted Hurwitz numbers.

Keywords

Cite

@article{arxiv.2002.07935,
  title  = {Weighted Hurwitz numbers, $\tau$-functions and matrix integrals},
  author = {J. Harnad},
  journal= {arXiv preprint arXiv:2002.07935},
  year   = {2021}
}

Comments

11 pages. Text of invited presentation at: Quantum Theory and Symmetries, XIth International symposium, Centre de recherches math\'ematiques, Montr\'eal, July 1-5, 2019

R2 v1 2026-06-23T13:46:12.805Z