A fixed point theorem for transformations whose iterates have uniform Lipschitz constant
In this paper, we will give a new fixed point theorem for lower semicontinuous multimaps in a Hausdorff topological vector space.
We extend the Fuglede-Putnam theorem modulo the Hilbert-Schmidt class to almost normal operators with finite Hilbert-Schmidt modulus of quasi-triangularity.
For a holomorphic function ψ defined on a sector we give a condition implying the identity where A is a sectorial operator on a Banach space X. This yields all common descriptions of the real interpolation spaces for sectorial operators and allows easy proofs of the moment inequalities and reiteration results for fractional powers.