Local theory of almost split sequences for comodules

Thumbnail Image

Date

Authors

Journal Title

Journal ISSN

Volume Title

Publisher

Abstract

Description

We show that almost split sequences in the category of comodules over a coalgebra with finite-dimensional right-hand term are direct limits of almost split sequences over finite dimensional subcoalgebras. In previous work we showed that such almost split sequences exist if the right hand term has a quasifinitely copresented linear dual. Conversely, taking limits of almost split sequences over finte-dimensional comodule categories, we then show that, for countable-dimensional coalgebras, certain exact sequences exist which satisfy a condition weaker than being almost split, which we call ``finitely almost split''. Under additional assumptions, these sequences are shown to be almost split in the appropriate category.

Keywords

Representation Theory, Rings and Algebras, 16G70, 16W30

Citation

URI

http://salesiana.dossiersoluciones.com/handle/123456789/74796

Consulte el texto completo en el siguiente enlace:

https://arxiv.org/abs/math/0504081
 http://arxiv.org/abs/math/0504081

Collections

arXiv