English

An insertion algorithm for multiplying Demazure characters by Schur polynomials

Combinatorics 2023-04-04 v2 Algebraic Geometry Representation Theory

Abstract

We introduce an insertion algorithm on Kohnert's combinatorial model for Demazure characters, generalizing Robinson--Schensted--Knuth insertion on tableaux. Our new insertion yields an explicit, nonnegative formula expressing the product of a Demazure character and a Schur polynomial as a sum of Schubert characters, partially resolving Polo's conjecture that the tensor product of Demazure modules admits a Schubert filtration.

Keywords

Cite

@article{arxiv.2109.05651,
  title  = {An insertion algorithm for multiplying Demazure characters by Schur polynomials},
  author = {Sami H. Assaf},
  journal= {arXiv preprint arXiv:2109.05651},
  year   = {2023}
}

Comments

23 pages, 16 (colored) figures plus an appendix with additional examples

R2 v1 2026-06-24T05:54:02.912Z