English

Three Examples of Quasisymmetric Compatible $\mathfrak{S}_n$-modules

Combinatorics 2024-05-20 v2

Abstract

The Schur functions, a basis for the symmetric polynomials (Sym), encode the irreducible representations of the symmetric group, Sn\mathfrak{S}_n, via the Frobenius characteristic map. In 1996, Krob and Thibon defined a quasisymmetric Frobenius map on the representations of Hn(0)\mathcal{H}_n(0), mapping them to the quasisymmetric functions (QSym). Despite the obvious inclusion of Sym in QSym and the close relationship between Sn\mathfrak{S}_n and Hn(0)\mathcal{H}_n(0), there is no known direct link between these two Frobenius characteristic maps and the related representations. We explore three specific situations in which a deformation of an Sn\mathfrak{S}_n action results in a valid Hn(0)\mathcal{H}_n(0) action and gives a quasisymmetric Frobenius characteristic that is equal to the symmetric Frobenius characteristic. We introduce the concept of quasisymmetric compatibility, which formalizes a link between the two maps, and we show it applies to all Sn\mathfrak{S}_n-modules.

Keywords

Cite

@article{arxiv.2403.16249,
  title  = {Three Examples of Quasisymmetric Compatible $\mathfrak{S}_n$-modules},
  author = {Angela Hicks and Samantha Miller-Brown},
  journal= {arXiv preprint arXiv:2403.16249},
  year   = {2024}
}

Comments

21 pages, 3 figures

R2 v1 2026-06-28T15:31:51.030Z