Almost complete cluster tilting objects in generalized higher cluster categories

Abstract: We study higher cluster tilting objects in generalized higher cluster categories arising from dg algebras of higher Calabi-Yau dimension. Taking advantage of silting mutations of Aihara-Iyama, we obtain a class of $m$-cluster tilting objects in generalized $m$-cluster categories. For generalized $m$-cluster categories arising from strongly ($m+2$)-Calabi-Yau dg algebras, by using truncations of minimal cofibrant resolutions of simple modules, we prove that each almost complete $m$-cluster tilting $P$-object has exactly $m+1$ complements with periodicity property. This leads us to the conjecture that each liftable almost complete $m$-cluster tilting object has exactly $m+1$ complements in generalized $m$-cluster categories arising from $m$-rigid good completed deformed preprojective dg algebras.