New posts in Category Theory

Why is it the (group) morphisms that matter?

Let $\epsilon$ be a topos and let $f:Y\to X$ be a morphism. Let $M,N$ be two subobjects of $X$. Is it true that $f^*(M\cap N)=f^*(M)\cap f^*(N)$?

Left adjoint to inclusion functor of torsion-free abelian groups in abelian groups

Origin of Grothendieck universes

Is a sequential limit of homeomorphisms a homeomorphism?

A monic coalgebra morphism whose underlying $\text{Set}$ morphism is not injective

(Soft Question) What kinds of properties are transferred by isomorphisms?

Coproduct of free monoids.

Completeness of the category of enriched categories

Are epimorphisms in the category of Stone spaces surjective?