Vertices of Schubitopes
Combinatorics
2020-08-14 v2
Abstract
Schubitopes were introduced by Monical, Tokcan and Yong as a specific family of generalized permutohedra. It was proven by Fink, M\'esz\'aros and St.Dizier that Schubitopes are the Newton polytopes of the dual characters of flagged Weyl modules. Important cases of Schubitopes include the Newton polytopes of Schubert polynomials and key polynomials. In this paper, we develop a combinatorial rule to generate the vertices of Schubitopes. As an application, we show that the vertices of the Newton polytope of a key polynomial can be generated by permutations in a lower interval in the Bruhat order, settling a conjecture of Monical, Tokcan and Yong.
Cite
@article{arxiv.1910.02816,
title = {Vertices of Schubitopes},
author = {Neil J. Y. Fan and Peter L. Guo},
journal= {arXiv preprint arXiv:1910.02816},
year = {2020}
}
Comments
19 pages, to appear in Journal of Combinatorial Theory, Series A