A note on locally convex spaces with a basic sequence of -disks
Denote by the commutator of two bounded operators and acting on a locally convex topological vector space. If , we show that is a quasinilpotent operator and we prove that if is a compact operator, then is a Riesz operator.
Some results about the continuity of special linear maps between -spaces recently obtained by Drewnowski have motivated us to revise a closed graph theorem for quasi-Suslin spaces due to Valdivia. We extend Valdivia’s theorem by showing that a linear map with closed graph from a Baire tvs into a tvs admitting a relatively countably compact resolution is continuous. This also applies to extend a result of De Wilde and Sunyach. A topological space is said to have a (relatively countably) compact...
For a given bi-continuous semigroup on a Banach space we define its adjoint on an appropriate closed subspace of the norm dual . Under some abstract conditions this adjoint semigroup is again bi-continuous with respect to the weak topology . We give the following application: For a Polish space we consider operator semigroups on the space of bounded, continuous functions (endowed with the compact-open topology) and on the space of bounded Baire measures (endowed with the weak-topology)....