English

Transfer of homological objects in exact categories via adjoint triples. Applications to functor categories

Category Theory 2024-07-08 v1 Representation Theory

Abstract

For a given family {(qi,ti,pi)}iI\{(\mathrm{q}_i, \mathrm{t}_i, \mathrm{p_i} )\}_{i \in I} of adjoint triples between exact categories C\mathcal{C} or D\mathcal{D}, we show that any cotorsion pair in C\mathcal{C} and D\mathcal{D} yield two canonical cotorsion pairs providing a concrete description of objects without using any injectives/projectives object hypothesis. We firstly apply this result for the evaluation functor on the functor category Add(A,R\mboxMod)\operatorname{Add}(\mathcal{A}, R \mbox{-Mod}) equipped with an exact structure E\mathcal{E}. Under mild conditions on A\mathcal{A}, we introduce the stalk functor at any object of A\mathcal{A}, and subsequently, we investigate cotorsion pairs induced by stalk functors. Finally, we use them to present an intrinsic characterization of projective/injective objects in (\mboxAdd(A,R\mboxMod);E)(\mbox{Add}(\mathcal{A}, R\mbox{-Mod}); \mathcal{E}).

Keywords

Cite

@article{arxiv.2407.04012,
  title  = {Transfer of homological objects in exact categories via adjoint triples. Applications to functor categories},
  author = {Sergio Estrada and Manuel Cortés-Izurdiaga and Sinem Odabasi},
  journal= {arXiv preprint arXiv:2407.04012},
  year   = {2024}
}