collaborators

7 papers

math.CO2026

Grassmannian quantum cohomology in the infinite limit and total positivity

Ines Chung-Halpern, Konstanze Rietsch

The theory of total positivity was shown by Lusztig to be intrinsically linked to the canonical basis with its positivity properties. When we restrict ourselves to studying total p…

math.CO2025

Totally positive Toeplitz matrices: classical and modern

Konstanze Rietsch

By a theorem of Edrei, an infinite, normalised totally nonnegative upper-triangular Toeplitz matrix is determined by a pair of nonnegative parameter sequences, the `Schoenberg para…

math.RT2025

Tropical Toeplitz matrices and parametrisations

Konstanze Rietsch

The set of infinite upper-triangular totally positive Toeplitz matrices has a classical parametrisation proved by Edrei et al and originally conjectured by Schoenberg, that involve…

math.AG2025

The tropical critical point and mirror symmetry

Jamie Judd, Konstanze Rietsch

Call a Laurent polynomial `complete' if its Newton polytope is full-dimensional with zero in its interior. We show that if is any complete Laurent polynomial with coefficie…

math.AG2025

A superpotential for Grassmannian Schubert varieties

Konstanze Rietsch, Lauren Williams

While mirror symmetry for flag varieties and Grassmannians has been extensively studied, Schubert varieties in the Grassmannian are singular, and hence standard mirror symmetry sta…

math.AG2025

An anticanonical perspective on G/P Schubert varieties

Changzheng Li, Konstanze Rietsch, Mingzhi Yang

We describe a natural basis of the Cartier class group of an arbitrary Schubert variety in a flag variety of general Lie type. We then characterise when the Schuber…