We initiate a general study of ultraproducts of C*-algebras, including topics on representations, homomorphisms, isomorphisms, positive linear maps and their ultraproducts. We partially settle a… Expand

<abstract abstract-type="TeX"><p>We apply Voiculescu's free entropy to show that free group factors do not possess a simple maximal abelian self-adjoint subalgebra, hence answering a longstanding… Expand

A new class of operator algebras, Kadison–Singer algebras (KS-algebras), is introduced. These highly noncommutative, non-self-adjoint algebras generalize triangular matrix algebras. They are… Expand

We prove that the ultrapower and the central sequence algebra of the
hyperfinite II1 factor are prime factors which implies that the central sequence
algebra of the tensor product of two factors may… Expand

Operator means and spectral decomposability in ergodic theory and Hilbert space operator theory by E. Berkson and T. A. Gillespie Some remarks on Toeplitz operators on discrete groups by X. Chen and… Expand