A. Engel

collaborators

3 papers

math.KT2025

Additive C*-categories and K-theory

Ulrich Bunke, Alexander Engel

We review the notions of a multiplier category and the $W^{*}$ -envelope of a $C^{*}$ -category. We then consider the notion of an orthogonal sum of a (possibly infinite) family of o…

math.AT2025

Paschke duality and assembly maps

Ulrich Bunke, Alexander Engel, Markus Land

We construct a natural transformation between two versions of $G$ -equivariant $K$ -homology with coefficients in a $G$ - $C^{*}$ -category for a countable discrete group $G$ . Its domai…

math.OA2025

A stable $\infty$ -category for equivariant $K K$ -theory

Ulrich Bunke, Alexander Engel, Markus Land

For a countable group $G$ we construct a small, idempotent complete, symmetric monoidal, stable $\infty$ -category $KK_{sep}^{G}$ whose homotopy category recovers…

Additive C*-categories and K-theory

Paschke duality and assembly maps

A stable ∞-category for equivariant KK-theory

A stable $\infty$ -category for equivariant $K K$ -theory