Title: Homological algebra for some Mackey functors Abstract: Bredon cohomology is a version of equivariant singular cohomology that is graded by the real representation ring RO(G). There are some fundamental difficulties in working with this theory, for example there are almost no known complete descriptions of the coefficient ring (i.e. the cohomology of a point). This boils down to a purely algebraic problem of computing the multi-graded endomorphisms of the unit in a certain derived category. I will describe some current work aimed at understanding this derived category from the ground up. This is joint work with Christy Hazel.

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Last modified: Mon Sep 29 11:59:37 EDT 2025