Lower and upper bounds of Schur characters
Abstract
Characterizations of lower and upper bounds for dual characters of flagged Weyl modules have attracted considerable interest. In this paper, we establish explicit pattern avoidance characterizations for lower and upper bounds of Schur characters, namely, the dual characters of Weyl modules associated with arbitrary diagrams. This setting extends the corresponding extremal problems for dual characters of flagged Weyl modules and includes skew Schur polynomials and, through Rothe diagrams, Stanley symmetric functions. Specifically, for a permutation w, we show that the Stanley symmetric function Fw attains the lower bound if and only if w avoids $321,2143,2413,3142$, and $3412$, and attains the upper bound if and only if w avoids $312$ and $321$.
Related
- Upper Bounds on the de Bruijn-Newman constant for Dirichlet L-functions with primitive real-valued characters
- Explicit upper and lower bounds on certain functions related to ζ(s) for s>1
- Upper and lower bounds for heat kernels with very strong degeneracy
- Sharp upper and lower bounds on the variance of U-statistics
- On the lower- and upper bounds of three-colored anti-Ramsey numbers
BibTeX
@misc{lin2026lower,
title = {{Lower and upper bounds of Schur characters}},
author = {Zhuowei Lin and Candice X. T. Zhang and Zhong-Xue Zhang},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.02050},
eprint = {2609.02050},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.02050},
}
RIS
TY - UNPB
TI - Lower and upper bounds of Schur characters
AU - Zhuowei Lin
AU - Candice X. T. Zhang
AU - Zhong-Xue Zhang
PY - 2026
DA - 2026/09/02
PB - arXiv
DO - 10.48550/arxiv.2609.02050
UR - https://arxiv.org/abs/2609.02050
AB - Characterizations of lower and upper bounds for dual characters of flagged Weyl modules have attracted considerable interest. In this paper, we establish explicit pattern avoidance characterizations for lower and upper bounds of Schur characters, namely, the dual characters of Weyl modules associated with arbitrary diagrams. This setting extends the corresponding extremal problems for dual characters of flagged Weyl modules and includes skew Schur polynomials and, through Rothe diagrams, Stanley symmetric functions. Specifically, for a permutation w, we show that the Stanley symmetric function F_w attains the lower bound if and only if w avoids $321,2143,2413,3142$, and $3412$, and attains the upper bound if and only if w avoids $312$ and $321$.
ER -