We study the quasi-weakly compact operators between normed spaces, which are described in terms of their first and second conjugates. Using a result on factorisation of an arbitrary linear operator ...

Banach spaces, as complete normed vector spaces, have long served as a fundamental framework for analysing linear operators. Operator theory within these spaces investigates the properties and ...

We give an example of an operator with different weak and strong absolutely continuous subspaces, and a counterexample to the duality problem for the spectral components. Both examples are optimal in ...