Chevalley formulae for the motivic Chern classes of Schubert cells and for the stable envelopes

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Mihalcea, Leonardo C., Naruse, Hiroshi, Su, Changjian
Format: Preprint
Published: 2023
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866914418034475008
author Mihalcea, Leonardo C.
Naruse, Hiroshi
Su, Changjian
author_facet Mihalcea, Leonardo C.
Naruse, Hiroshi
Su, Changjian
contents We prove a Chevalley formula to multiply the motivic Chern classes of Schubert cells in a generalized flag manifold $G/P$ by the class of any line bundle $\mathcal{L}_λ$. Our formula is given in terms of the $λ$-chains of Lenart and Postnikov. Its proof relies on a change of basis formula in the affine Hecke algebra due to Ram, and on the Hecke algebra action on torus-equivariant K-theory of the complete flag manifold $G/B$ via left Demazure--Lusztig operators. We revisit some wall-crossing formulae for the stable envelopes in $T^*(G/B)$. We use our Chevalley formula, and the equivalence between motivic Chern classes of Schubert cells and K-theoretic stable envelopes in $T^*(G/B)$, to give formulae for the change of polarization, and for the change of slope for stable envelopes. We prove several additional applications, including Serre, star, and Dynkin, dualities of the Chevalley coefficients, new formulae for the Whittaker functions, and for the Hall--Littlewood polynomials. We also discuss positivity properties of Chevalley coefficients, and properties of the coefficients arising from multiplication by minuscule weights.
format Preprint
id arxiv_https___arxiv_org_abs_2312_17200
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Chevalley formulae for the motivic Chern classes of Schubert cells and for the stable envelopes
Mihalcea, Leonardo C.
Naruse, Hiroshi
Su, Changjian
Algebraic Geometry
Combinatorics
Representation Theory
14M15, 14C17 (Primary), 14N15, 17B10, 33D80 (Secondary)
We prove a Chevalley formula to multiply the motivic Chern classes of Schubert cells in a generalized flag manifold $G/P$ by the class of any line bundle $\mathcal{L}_λ$. Our formula is given in terms of the $λ$-chains of Lenart and Postnikov. Its proof relies on a change of basis formula in the affine Hecke algebra due to Ram, and on the Hecke algebra action on torus-equivariant K-theory of the complete flag manifold $G/B$ via left Demazure--Lusztig operators. We revisit some wall-crossing formulae for the stable envelopes in $T^*(G/B)$. We use our Chevalley formula, and the equivalence between motivic Chern classes of Schubert cells and K-theoretic stable envelopes in $T^*(G/B)$, to give formulae for the change of polarization, and for the change of slope for stable envelopes. We prove several additional applications, including Serre, star, and Dynkin, dualities of the Chevalley coefficients, new formulae for the Whittaker functions, and for the Hall--Littlewood polynomials. We also discuss positivity properties of Chevalley coefficients, and properties of the coefficients arising from multiplication by minuscule weights.
title Chevalley formulae for the motivic Chern classes of Schubert cells and for the stable envelopes
topic Algebraic Geometry
Combinatorics
Representation Theory
14M15, 14C17 (Primary), 14N15, 17B10, 33D80 (Secondary)
url https://arxiv.org/abs/2312.17200