Mathematik und Statistik

KWIM & RGA SS24: Coupled Cluster Degree of the Grassmannian

Time
Friday, 19. July 2024
13:30 - 15:00

Location
F 426

Organizer
Prof. Dr. Mateusz Michalek & KWIM

Speaker:
Viktoriia Borovik

This event is part of an event series „Konstanz Women in Mathematics Lecture Series“.

We determine the number of complex solutions to a nonlinear eigenvalue problem on the Grassmannian in its Plücker embedding. This is motivated by quantum chemistry, where it represents the truncation to single electrons in coupled cluster theory. In the case of the Grassmannian of lines, we obtain an explicit formula for the number of complex solutions, which involves Catalan numbers and is the volume of the Cayley sum of the Gelfand-Cetlin polytope with simplex. This rests on the geometry of the graph of a birational parametrization of the Grassmannian. This is joint work with Bernd Sturmfels and Svala Sverrisdóttir.