2015/04/15 by J. Adámek, Adamek, Jiri, Jiřı́ Rosický +1 · 1 citation
Mathematics · Computer Science · #Homotopy and Cohomology in Algebraic Topology #Logic, Reasoning, and Knowledge #Rings, Modules, and Algebras
paper · pdf · doi:10.48550/arxiv.1504.03886
Are all subcategories of locally finitely presentable categories that are closed under limits and λ-filtered colimits also locally presentable? For full subcategories the answer is affirmative. Makkai and Pitts proved that in the case λ=ℵ0 the answer is affirmative also for all iso-full subcategories, i.\thinspace e., those containing with every pair of objects all isomorphisms between them. We discuss a possible generalization of this from ℵ0 to an arbitrary λ.