{ "id": "2310.20571", "version": "v1", "published": "2023-10-31T16:01:18.000Z", "updated": "2023-10-31T16:01:18.000Z", "title": "Regular Schur labeled skew shape posets and their 0-Hecke modules", "authors": [ "Young-Hun Kim", "So-Yeon Lee", "Young-Tak Oh" ], "comment": "44 pages", "categories": [ "math.RT", "math.CO" ], "abstract": "Assuming Stanley's $P$-partition conjecture holds, the regular Schur labeled skew shape posets with underlying set $\\{1,2,\\ldots, n\\}$ are precisely the posets $P$ such that the $P$-partition generating function is symmetric and the set of linear extensions of $P$, denoted $\\Sigma_L(P)$, is a left weak Bruhat interval in the symmetric group $\\mathfrak{S}_n$. We describe the permutations in $\\Sigma_L(P)$ in terms of reading words of standard Young tableaux when $P$ is a regular Schur labeled skew shape poset, and classify $\\Sigma_L(P)$'s up to descent-preserving isomorphism as $P$ ranges over regular Schur labeled skew shape posets. The results obtained are then applied to classify the $0$-Hecke modules $\\mathsf{M}_P$ associated with regular Schur labeled skew shape posets $P$ up to isomorphism. Then we characterize regular Schur labeled skew shape posets as the posets whose linear extensions form a dual plactic-closed subset of $\\mathfrak{S}_n$. Using this characterization, we construct distinguished filtrations of $\\mathsf{M}_P$ with respect to the Schur basis when $P$ is a regular Schur labeled skew shape poset. Further issues concerned with the classification and decomposition of the $0$-Hecke modules $\\mathsf{M}_P$ are also discussed.", "revisions": [ { "version": "v1", "updated": "2023-10-31T16:01:18.000Z" } ], "analyses": { "subjects": [ "20C08", "06A07", "05E10", "05E05" ], "keywords": [ "schur labeled skew shape poset", "regular schur labeled skew shape", "hecke modules", "left weak bruhat interval", "linear extensions" ], "note": { "typesetting": "TeX", "pages": 44, "language": "en", "license": "arXiv", "status": "editable" } } }