You are here

Quantum Bruhat graphs and tilted Richardson varieties

Shiliang Gao, University of Illinois at Urbana-Champaign
Wednesday, October 25, 2023 - 3:30pm to 5:00pm
PDL C-401 and via Zoom Link:


A two-point curve neighborhood is the union of degree \(d\) rational curves that pass through two given Schubert varieties in the flag variety. These varieties were introduced by Buch-Chaput-Mihalcea-Perrin in 2013. They encode information about the 3-point Gromov-Witten invariants of the flag variety. Postnikov proved there is a unique minimal degree where the curve neighborhood is non-empty and described it using the quantum Bruhat graph. In this case, we provide a concrete description of the curve neighborhood in terms of the combinatorics of tilted Bruhat order and a stratification with open tilted Richardson varieties. This is joint work with Jiyang Gao and Yibo Gao.

Note: This talk begins with a pre-seminar (aimed at graduate students) at 3:30–4:00. The main talk starts at 4:10.

Join Zoom Meeting:
Meeting ID: 915 4733 5974