English

Fractionally Calabi-Yau algebras and cluster tilting

Representation Theory 2026-04-22 v1

Abstract

We show that the class of twisted fractionally Calabi-Yau algebras of finite global dimension coincides with the stable endomorphism algebras of dd-cluster tilting modules over dd-representation-finite algebras. This is an application of our main result stating that an algebra AA of finite global dimension is twisted fractionally Calabi-Yau if and only if there exists ii such that the replicated algebra A(i)A^{(i)} is a higher Auslander algebra if and only if there exist infinitely many ii such that A(i)A^{(i)} is a higher Auslander algebra. This gives a new connection between the study of higher Auslander-Reiten theory and twisted fractionally Calabi-Yau algebras, and provides a new construction of large classes of higher Auslander algebras and higher representation-finite algebras. We give several applications such as an explicit characterisation of twisted n2\frac{n}{2}-Calabi-Yau algebras, and a triangle equivalence between the bounded derived category of a twisted fractionally Calabi-Yau algebra of finite global dimension and the Z\mathbb{Z}-graded stable module category of an associated higher preprojective algebra.

Keywords

Cite

@article{arxiv.2604.19582,
  title  = {Fractionally Calabi-Yau algebras and cluster tilting},
  author = {Aaron Chan and Osamu Iyama and Rene Marczinzik},
  journal= {arXiv preprint arXiv:2604.19582},
  year   = {2026}
}