6 papers
Cosyzygy modules
Petter Andreas Bergh, David A. Jorgensen, Peder Thompson
We characterize all first cosyzygy modules of a given finitely generated module over a local ring. We do this by introducing the notion of a canonical cosyzygy module, and showing…
On the cohomology of finite tensor categories
Petter Andreas Bergh
It has been conjectured that finite tensor categories have finitely generated cohomology. We show that this is equivalent to finitely generated Hochschild cohomology for the endomo…
Asymptotic vanishing of cohomology in triangulated categories
Petter Andreas Bergh, David A. Jorgensen, Peder Thompson
Given a graded-commutative ring acting centrally on a triangulated category, our main result shows that if cohomology of a pair of objects of the triangulated category is finitely…
On the representation type of a finite tensor category
Petter Andreas Bergh, Karin Erdmann, Julia Yael Plavnik +1
Given an exact module category over a finite tensor category with finitely generated cohomology, we show that if there exists an object of complexity at least three, then the categ…
Multiplicity in triangulated categories
Petter Andreas Bergh, David A. Jorgensen, Peder Thompson
We lay out the theory of a multiplicity in the setting of a triangulated category having a central ring action from a graded-commutative ring , in other words, an -linear tri…
Dimension and depth inequalities over complete intersections
Petter Andreas Bergh, David A. Jorgensen, Peder Thompson
For a pair of finitely generated modules and over a codimension complete intersection ring with finite, we pay special attention to the inequali…