paper

The quasisymmetric flag variety: a toric complex on noncrossing partitions

arXiv:2508.12171 · doi:10.1017/fmp.2026.10034

Abstract

We develop the geometric theory of equivariant quasisymmetry via a new ``quasisymmetric flag variety''. This is a toric complex in the flag variety whose fixed point set is the set of noncrossing partitions, and whose cohomology ring is the ring of quasisymmetric coinvariants.