Tuesday 22 February 2022, 16:00-17:00 in HG03.054
Steffen Sagave (RU)
A strictly commutative model for the cochain algebra of a space
The cochain algebra of a topological space is a differential graded algebra whose cohomology groups are the singular cohomology groups of the space. In this talk, I will explain how extra symmetries encoded by the category of finite sets and injections allow to construct a refined version of the cochain algebra whose multiplication is commutative in a suitable sense. This generalizes a classical construction from rational homotopy theory and provides a very fine algebraic invariant of topological spaces. This is joint work with Birgit Richter.