arXiv subjects
Publications and source records attributed to L. Aagaard.
We give a Banach algebra approach to the additiveness property of Voiculescu's amalgamated R-transform. We also define an amalgamated S-transform and prove that it is multiplicative on products of amalgamated free random variables when the algebra of amalgamation is commutative.
Let T be the quasi-nilpotent DT-operator. By use of Voiculescu's amalgamated R-transform we compute the moments of $(T-λ1)^*(T-λ1)$, where $λ\in \mathbb C$, and the Brown-measure of $T+\sqrtε Y$, where Y is a circular element *-free from T for $ε>0$. Moreover we give a new proof of Śniady's formula for the moments $τ(((T^*)^k T^k)^n)$ for $k,n\in \mathbb N$.