Algebra/Topology Seminar 27112020

Speaker: Lars Hesselholt

Title: Dirac geometry

Abstract: This talk is a report on joint work in progress with Piotr Pstragowski. Our purpose is to argue that, in higher algebra, there exists an intrinsic structure akin to spin that manifests itself through the fact that the homotopy groups of a commutative algebra form a commutative algebra in the symmetric monoidal category of graded abelian groups. The geometry built from such algebras, which we call Dirac geometry, is a natural extension of G_m-equivariant geometry in which half-integer Serre twists exist.