Affine Weyl groups in K-theory and representation theory

dc.creatorLenart, Cristian
dc.creatorPostnikov, Alexander
dc.date2003-09-12
dc.date2005-06-28
dc.date.accessioned2026-07-07T05:01:04Z
dc.date.available2026-07-07T05:01:04Z
dc.descriptionWe give an explicit combinatorial Chevalley-type formula for the equivariant K-theory of generalized flag varieties G/P which is a direct generalization of the classical Chevalley formula. Our formula implies a simple combinatorial model for the characters of the irreducible representations of G and, more generally, for the Demazure characters. This model can be viewed as a discrete counterpart of the Littelmann path model, and has several advantages. Our construction is given in terms of a certain R-matrix, that is, a collection of operators satisfying the Yang-Baxter equation. It reduces to combinatorics of decompositions in the affine Weyl group and enumeration of saturated chains in the Bruhat order on the (nonaffine) Weyl group. Our model easily implies several symmetries of the coefficients in the Chevalley-type formula. We also derive a simple formula for multiplying an arbitrary Schubert class by a divisor class, as well as a dual Chevalley-type formula. The paper contains other applications and examples.
dc.descriptionv2: Major revision: several new sections and an appendix added, references added, exposition improved. New material includes: generalization to G/P, two symmetries of coefficients, Pieri-type formula, dual Chevalley-type formula, a conjecture for quantum K-theory. v3: Minor updates and corrections
dc.identifierhttps://arxiv.org/abs/math/0309207
dc.identifierhttp://arxiv.org/abs/math/0309207
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/68548
dc.subjectRepresentation Theory
dc.subjectAlgebraic Geometry
dc.subjectCombinatorics
dc.subjectPrimary 22E46; Secondary 14M15, 19E08
dc.titleAffine Weyl groups in K-theory and representation theory
dc.typetext

Files

Collections