Annihilators of nilpotent elements.
The problem of when derivations (and their powers) have the range in the Jacobson radical is considered. The proofs are based on the density theorem for derivations.
Let be a prime ring of characteristic different from 2, its right Martindale quotient ring and its extended centroid. Suppose that , are generalized skew derivations of with the same associated automorphism , and is a non-central polynomial over such that for all . Then there exists such that for all .
The purpose of this paper is to investigate identities satisfied by centralizers on prime and semiprime rings. We prove the following result: Let be a noncommutative prime ring of characteristic different from two and let and be left centralizers on . Suppose that is fulfilled for all . If
The main result: Let be a -torsion free semiprime ring and let be an additive mapping. Suppose that holds for all . In this case is a centralizer.
We consider rings equipped with a closure operation defined in terms of a collection of commuting idempotents, generalising the idea of a topological closure operation defined on a ring of sets. We establish the basic properties of such rings, consider examples and construction methods, and then concentrate on rings which have a closure operation defined in terms of their lattice of central idempotents.