Kaplansky Density for automorphism groups
Matt Daws (University of Central Lancashire)
Thursday 9th May, 2019 16:00-17:00 Maths 311B
We will discuss the Kaplansky Density result for operator algebras, and its failure for non-self-adjoint algebras. We will then turn our attention to automorphism groups of operator algebras, and in particular their "analytic generators". We will show that a Kaplansky Density type result holds for such generators: when we have an automorphism group of a von Neumann algebra which restricts to a sigma-weakly dense C*-subalgebra, the analytic generator of the C*-algebra group is sigma-weakly dense in that for the von Neumann algebra. This setup occurs in the theory of locally compact quantum groups, in particular, when the antipode is unbounded.