Cotangent Cohomology for Matroids

Abstract: The first cotangent cohomology module $T^1$ describes the first order deformations of a commutative ring. For Stanley-Reisner rings, this module has a purely combinatorial description: its multigraded components are given as the relative cohomology of some topological spaces associated to the defining simplicial complex. When the Stanley-Reisner ring is associated to a matroid, I will present a very explicit formula for the dimensions of these components. Furthermore, I will show that $T^1$ provides a new complete characterization for matroids.

algebraic geometrynumber theory

Audience: researchers in the discipline

SFU NT-AG seminar

Series comments: The Number Theory and Algebraic Geometry (NT-AG) seminar is a research seminar dedicated to topics related to number theory and algebraic geometry hosted by the NT-AG group (Nils Bruin, Imin Chen, Stephen Choi, Katrina Honigs, Nathan Ilten, Marni Mishna).

We acknowledge the support of PIMS, NSERC, and SFU.

For Fall 2025, the organizers are Katrina Honigs and Peter McDonald.

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