On the idempotence and stability of kernel functors
On the idempotence and stability of kernel functors
A kernel functor (equivalently, a left exact torsion preradical) is a left exact subfunctor of the identity on the category R -mod of left R -modules over a ring R with identity. A kernel functor is said to be idempotent if, in addition, σ satisfies σ( M / σ(M )) …