{ "id": "2303.09251", "version": "v1", "published": "2023-03-16T12:02:02.000Z", "updated": "2023-03-16T12:02:02.000Z", "title": "Parabolic recursions for Kazhdan-Lusztig polynomials and the hypercube decomposition", "authors": [ "Maxim Gurevich", "Chuijia Wang" ], "comment": "23 pages, comments welcome", "categories": [ "math.RT", "math.CO" ], "abstract": "We employ general parabolic recursion methods to demonstrate the recently devised hypercube formula for Kazhdan-Lusztig polynomials of $S_n$, and establish its generalization to the full setting of a finite Coxeter system through algebraic proof. We introduce procedures for positive decompositions of $q$-derived Kazhdan-Lusztig polynomials within this setting, that utilize classical Hecke algebra positivity phenomena of Dyer-Lehrer and Grojnowski-Haiman. This leads to a distinct algorithmic approach to the subject, based on induction from a parabolic subgroup. We propose suitable weak variants of the combinatorial invariance conjecture and verify their validity for permutation groups.", "revisions": [ { "version": "v1", "updated": "2023-03-16T12:02:02.000Z" } ], "analyses": { "keywords": [ "kazhdan-lusztig polynomials", "hypercube decomposition", "employ general parabolic recursion methods", "classical hecke algebra positivity phenomena" ], "note": { "typesetting": "TeX", "pages": 23, "language": "en", "license": "arXiv", "status": "editable" } } }