CARMA Seminar

4:00 pm

Thursday, 8th Sep 2011

V129, Mathematics Building


Prof John Giles

(School of Mathematical and Physical Sciences, The University of Newcastle)

Persistence properties for Banach spaces

We are interested in local geometrical properties of a Banach space which are preserved under natural embeddings in all even dual spaces. An example of this behaviour which we generalise is:

if the norm of the space $X$ is Fréchet differentiable at $x \in S(X)$ then the norm of the second dual $X^{**}$ is Fréchet differentiable at $\hat{x}\in S(X)$ and of $X^{****}$ at $\hat{\hat{x}} \in S(X^{****})$ and so on....

The results come from a study of Hausdorff upper semicontinuity properties of the duality mapping characterising general differentiability conditions satisfied by the norm.