English

Cluster combinatorics of d-cluster categories

Representation Theory 2009-02-14 v2 Combinatorics

Abstract

We study the cluster combinatorics of dd-cluster tilting objects in dd-cluster categories. By using mutations of maximal rigid objects in dd-cluster categories which are defined similarly for dd-cluster tilting objects, we prove the equivalences between dd-cluster tilting objects, maximal rigid objects and complete rigid objects. Using the chain of d+1d+1 triangles of dd-cluster tilting objects in [IY], we prove that any almost complete dd-cluster tilting object has exactly d+1d+1 complements, compute the extension groups between these complements, and study the middle terms of these d+1d+1 triangles. All results are the extensions of corresponding results on cluster tilting objects in cluster categories established in [BMRRT] to dd-cluster categories. They are applied to the Fomin-Reading's generalized cluster complexes of finite root systems defined and studied in [FR2] [Th] [BaM1-2], and to that of infinite root systems [Zh3].

Keywords

Cite

@article{arxiv.0712.1381,
  title  = {Cluster combinatorics of d-cluster categories},
  author = {Yu Zhou and Bin Zhu},
  journal= {arXiv preprint arXiv:0712.1381},
  year   = {2009}
}

Comments

correted many typos according to the referee's comments, final version to appear in J. Algebra

R2 v1 2026-06-21T09:52:12.889Z