Maximal zero product subrings and inner ideals of simple rings

Abstract Let Q be a (not necessarily unital) simple ring or algebra. A nonempty subset S of Q is said to have zero product if S 2 = 0 . We classify all maximal zero product subsets of Q by proving that the map R ↦ R ∩ LeftAnn ( R ) is a bijection from the set of all proper nonzero annihilator right ideals of Q onto the set of all maximal zero product subsets of Q. We also describe the relationship between the maximal zero product subsets of Q and the maximal inner ideals of its associated Lie algebra.