Zeros of quadratic functionals on non-separable spaces
We construct non-separable subspaces in the kernel of every quadratic functional on some classes of complex and real Banach spaces.
σ-fragmented Banach spaces II
Recent papers have investigated the properties of σ-fragmented Banach spaces and have sought to find which Banach spaces are σ-fragmented and which are not. Banach spaces that have a norming M-basis are shown to be σ-fragmented using weakly closed sets. Zizler has shown that Banach spaces satisfying certain conditions have locally uniformly convex norms. Banach spaces that satisfy similar, but weaker conditions are shown to be σ-fragmented. An example, due to R. Pol, is given of a Banach space that...
φ-regular functions in Asplund spaces