• Hochschild cohomology of some quantum complete intersections 

      Erdmann, Karin; Hellstrøm-Finnsen, Magnus (Journal article; Peer reviewed, 2018)
      We compute the Hochschild cohomology ring of the algebras A = kX, Y /(Xa,XY − qY X, Y a) over a field k where a ≥ 2 and where q ∈ k is a primitive ath root of unity. We find the dimension of HHn(A) and show that it is ...
    • Matrix factorizations for quantum complete intersections 

      Bergh, Petter Andreas; Erdmann, Karin (Peer reviewed; Journal article, 2019)
      We introduce twisted matrix factorizations for quantum complete intersections of codimension two. For such an algebra, we show that in a given dimension, almost all the indecomposable modules with bounded minimal projective ...
    • On the structure and cohomology ring of connected Hopf algebras 

      Erdmann, Karin; Solberg, Øyvind; Wang, Xingting (Peer reviewed; Journal article, 2019)
      Let p be a prime, and k be a field of characteristic p. We investigate the algebra structure and the structure of the cohomology ring for the connected Hopf algebras of dimension p3, which appear in the classification ...