English

Functional relations for higher-order free cumulants

Operator Algebras 2023-09-28 v2 Mathematical Physics Combinatorics math.MP Probability

Abstract

We establish the functional relations between generating series of higher-order free cumulants and moments in higher-order free probability, solving an open problem posed fifteen years ago by Collins, Mingo, \'Sniady and Speicher. We propose an extension of free probability theory, which governs the all-order topological expansion in unitarily invariant matrix ensembles, with a corresponding notion of free cumulants and give as well their relation to moments via functional relations. Our approach is based on the study of a master transformation involving double monotone Hurwitz numbers via semi-infinite wedge techniques, building on the recent advances of the last-named author with Bychkov, Dunin-Barkowski and Kazarian. We illustrate our formulas by computing the first few decaying terms of the correlation functions of an ensemble of spiked GUE matrices, going beyond the law of large numbers and the central limit theorem.

Keywords

Cite

@article{arxiv.2112.12184,
  title  = {Functional relations for higher-order free cumulants},
  author = {Gaëtan Borot and Séverin Charbonnier and Elba Garcia-Failde and Felix Leid and Sergey Shadrin},
  journal= {arXiv preprint arXiv:2112.12184},
  year   = {2023}
}

Comments

59 pages

R2 v1 2026-06-24T08:28:37.814Z