On the maximal support of a module

Abstract

If M is a finitely-generated module over a commutative noetherian ring, then it is well-known that the ideal-theoretic assassin and the ideal-theoretic support of M satisfy the following two conditions: (CD supp(M) and ass(M) have the same minimal elements ; (C2) supp(M) has only finitely-many minimal elements. The purpose of this note is to consider a sufficient condition on a noncommutative ring, generalizing the commutative case, for analogous results to hold for the torsion-theoretic assassin and the torsion-theore-tic support of suitable left R-modules M. Since the order in the lattice of torsion theories over the category R-mod of left R-modules is the reverse of the order in the lattice of left ideals of R, we would expect to substitute “maximal” for “minimal” in the above conditions. Also, noetherianness should be replaced by its torsion-theoretic counterpart, semi-noetherianness.