English

Two-row Delta Springer varieties

Representation Theory 2025-09-03 v2 Combinatorics Quantum Algebra

Abstract

We study the geometry and topology of Δ\Delta-Springer varieties associated with two-row partitions. These varieties were introduced in recent work by Griffin-Levinson-Woo to give a geometric realization of a symmetric function appearing in the Delta conjecture by Haglund-Remmel-Wilson. We provide an explicit and combinatorial description of the irreducible components of the two-row Δ\Delta-Springer variety and compare it to the ordinary two-row Springer fiber as well as Kato's exotic Springer fiber corresponding to a one-row bipartition. In addition to that, we extend the action of the symmetric group on the homology of the two-row Δ\Delta-Springer variety to an action of a degenerate affine Hecke algebra and relate this action to a gl2\mathfrak{gl}_{2}-tensor space.

Keywords

Cite

@article{arxiv.2407.10792,
  title  = {Two-row Delta Springer varieties},
  author = {Abel Lacabanne and Pedro Vaz and Arik Wilbert},
  journal= {arXiv preprint arXiv:2407.10792},
  year   = {2025}
}

Comments

v1: 32 pages, many figures, comments welcome; v2: 33 pages, many figures, reviewed version accepted in Algebraic Combinatorics, Theorem 4.1 was wrong and replaced by a counterexample

R2 v1 2026-06-28T17:41:23.505Z