An operator space characterization of dual operator algebras

This paper is devoted to dual algebras, that is w*-closed algebras of bounded operators on Hilbert space. We give abstract characterizations of unital dual algebras (resp. dual algebras) up to w*-homeomorphic unital complete isometry (resp. complete isomorphism). The results we obtain are natural w*-versions of analogous characterizations due to Blecher-Ruan-Sinclair and Blecher respectively, in the category of operator algebras.