Sequences of ICE-closed subcategories via preordered $\ddot{I}{„}^{-1}$-rigid modules

Abstract

Let $\hat{I}›$ be a finite-dimensional basic algebra. Sakai recently used certain sequences of image-cokernel-extension-closed (ICE-closed) subcategories of finitely generated $\hat{I}›$-modules to classify certain (generalized) intermediate $t$-structures in the bounded derived category. We classifying these "contravariantly finite ICE-sequences" using concepts from $\ddot{I}„$-tilting theory. More precisely, we introduce "cogen-preordered $\ddot{I}{„}^{-1}$-rigid modules" as a generalization of (the dual of) the "TF-ordered $\ddot{I}„$-rigid modules" of Mendoza and Treffinger. We then establish a bijection between the set of cogen-preordered $\ddot{I}{„}^{-1}$-rigid modules and certain sequences of intervals of torsion-free classes. Combined with the results of Sakai, this yields a bijection with the set of contravariantly finite ICE-sequences (of finite length), and thus also with the set of $(m+1)$-intermediate $t$-structures whose aisles are homology-determined.

15 pages