3 papers
math.CO2025
Bumpless Pipe Dream Fragments -- Equivariant Geometry of Clans
Yiming Chen, Neil J. Y. Fan, Rui Xiong +1
In this paper, we establish a new geometric setting for bumpless pipe dreams and double Schubert polynomials. Building on the notion of bumpless pipe dream fragments, we define cla…
math.RT2025
Quivers with Involutions and Shifted Twisted Yangians via Coulomb Branches
Yaolong Shen, Changjian Su, Rui Xiong
To a quiver with involution, we study the Coulomb branch of the 3d involution-fixed part of the quiver gauge theory. We show that there is an algebra homomorphism…
math.AG2025
Chern Classes of Open Projected Richardson Varieties and of Affine Schubert Cells
Neil J. Y. Fan, Peter L. Guo, Changjian Su +1
The open projected Richardson varieties form a stratification for the partial flag variety . We compare the Segre--MacPherson classes of open projected Richardson varieties wi…