activity
19962026
most citedHoneycombs and sums of Hermitian matrices

146 citations · 484 across the 48 of their papers we have counts for

collaborators

53 papers

math.AG2026

Permutahedra, Lusztig varieties, degenerations, and subdivisions

Allen Knutson, Mario Sanchez, Melissa Sherman-Bennett

We present an embedded (in ) degeneration of Lusztig varieties (which generalize type Hessenberg varieties) to certain unions of Richardson varieties, giving a simultaneou…

math.CO2023★ 2 cited

Schubert puzzles and integrability III: separated descents

Allen Knutson, Paul Zinn-Justin

In paper I of this series we gave positive formulae for expanding the product of two Schubert polynomials, in the case that both had shared desce…

math.SG2022

The Duistermaat-Heckman formula and Chern-Schwartz-MacPherson classes

Allen Knutson

Let M be a smooth complex projective variety, bearing a Kähler symplectic form ωand a Hamiltonian action of a torus T, with finitely many fixed points M^T. One standard form of the…

math.AG2021

A Bruhat atlas for the Mehta-van der Kallen stratification of

Allen Knutson, Steven V Sam

Mehta and van der Kallen put a Frobenius splitting on the type A cotangent bundle , thereby defining a stratification by compatibly split subvarieties, and they determi…

math.AG2021

Schubert puzzles and integrability II: multiplying motivic Segre classes

Allen Knutson, Paul Zinn-Justin

In Schubert Puzzles and Integrability I we proved several "puzzle rules" for computing products of Schubert classes in K-theory (and sometimes equivariant K-theory) of d-step flag…

math.CO2019★ 2 cited

Schubert polynomials, pipe dreams, equivariant classes, and a co-transition formula

Allen Knutson

We give a new proof that three families of polynomials coincide: the double Schubert polynomials of Lascoux and Schützenberger defined by divided difference operators, the pipe dre…