Tutte Colloquium - Stefan Weltge

Friday, November 25, 2022 3:30 pm - 3:30 pm EST (GMT -05:00)

Title: Integer programs with bounded subdeterminants and two nonzeros per row

Speaker: Stefan Weltge
Affiliation: Technical University of Munich
Location: MC 5501 or contact Eva Lee for Zoom link

Abstract: Determining the complexity of integer linear programs with integer coefficient matrices whose subdeterminants are bounded by a constant is currently a very actively discussed question in the field. In this talk, I will present a strongly polynomial-time algorithm for such integer programs with the further requirement that every constraint contains at most two variables. The core of our approach is the first polynomial-time algorithm for the weighted stable set problem on graphs that do not contain more than k vertex-disjoint odd cycles, where k is any constant. Previously, polynomial-time algorithms were only known for k = 0 (bipartite graphs) and for k = 1.

This is joint work with Samuel Fiorini, Gwenaël Joret, and Yelena Yuditsky, which recently appeared at FOCS this year.