Differential identities, Lie ideals, and Posner’s theorems
Differential identities, Lie ideals, and Posner’s theorems
Two well-known results of E. C. Posner state that the composition of two nonzero derivations of a prime ring cannot be a nonzero derivation, and that in a prime ring, if the commutator of each element and its image under a nonzero derivation is central, then the ring is commutative.Our …