Abelian categories, almost split sequences, and comodules

Mark Kleiner, Idun Reiten

Research output: Contribution to journalArticlepeer-review

12 Scopus citations


The following are equivalent for a skeletally small abelian Hornfinite category over a field with enough injectives and each simple object being an epimorphic image of a projective object of finite length. (a) Each indecomposable injective has a simple subobject. (b) The category is equivalent to the category of socle-finitely copresented right comodules over a right semiperfect and right cocoherent coalgebra such that each simple right comodule is socle-finitely copresented. (c) The category has left almost split sequences.

Original languageEnglish (US)
Pages (from-to)3201-3214
Number of pages14
JournalTransactions of the American Mathematical Society
Issue number8
StatePublished - Aug 2005


  • Abelian category
  • Almost split sequence
  • Comodule
  • Semiperfect cocoherent coalgebra

ASJC Scopus subject areas

  • General Mathematics
  • Applied Mathematics


Dive into the research topics of 'Abelian categories, almost split sequences, and comodules'. Together they form a unique fingerprint.

Cite this