English

A representability theorem for some huge abelian categories

Category Theory 2012-05-11 v3

Abstract

We define quasi--locally presentable categories as big unions of coreflective subcategories which are locally presentable. Under appropriate hypotheses we prove a representability theorem for exact contravariant functors defined on a quasi--locally presentable category taking values in abelian groups. We show that the abelianization of a well generated triangulated category is quasi--locally presentable and we obtain a new proof of Brown representability theorem. Examples of functors which are not representable are also given.

Keywords

Cite

@article{arxiv.1003.5937,
  title  = {A representability theorem for some huge abelian categories},
  author = {George Ciprian Modoi},
  journal= {arXiv preprint arXiv:1003.5937},
  year   = {2012}
}

Comments

In the new version it is given a stronger definition for the notion of quasi--locally presentable category. An already known result was removed. To appear Homotopy, Homology and Applications

R2 v1 2026-06-21T15:04:45.986Z