The singular locus of regular Hessenberg varieties
Martha Precup

Washington University in St. Louis

Hessenberg varieties are subvarieties of the flag variety with important
connections to representation theory, algebraic geometry, and combinatorics.
Like Schubert varieties, the structure of Hessenberg varieties can be
studied using the combinatorics of the symmetric group. In this talk, we
will define these varieties and compute their Betti numbers. Then we’ll
give a combinatorial criterion for identifying singular points in certain
regular Hessenberg varieties. These results are joint work with Erik Insko
and Alex Woo.