English

Tensor products of n-complete algebras

Representation Theory 2019-04-09 v2

Abstract

If AA and BB are nn- and mm-representation finite kk-algebras, then their tensor product Λ=AkB\Lambda = A\otimes_k B is not in general (n+m)(n+m)-representation finite. However, we prove that if AA and BB are acyclic and satisfy the weaker assumption of nn- and mm-completeness, then Λ\Lambda is (n+m)(n+m)-complete. This mirrors the fact that taking higher Auslander algebra does not preserve dd-representation finiteness in general, but it does preserve dd-completeness. As a corollary, we get the necessary condition for Λ\Lambda to be (n+m)(n+m)-representation finite which was found by Herschend and Iyama by using a certain twisted fractionally Calabi-Yau property.

Keywords

Cite

@article{arxiv.1701.03325,
  title  = {Tensor products of n-complete algebras},
  author = {Andrea Pasquali},
  journal= {arXiv preprint arXiv:1701.03325},
  year   = {2019}
}

Comments

16 pages. Minor changes following referee report