Quantcast

Convex Combinations of Weak*-Convergent Sequences and the Mackey Topology

Research paper by Antonio Avilés, José Rodríguez

Indexed on: 20 Sep '16Published on: 10 Sep '16Published in: Mediterranean Journal of Mathematics



Abstract

Abstract A Banach space X is said to have property (K) if every w*-convergent sequence in X* admits a convex block subsequence which converges with respect to the Mackey topology. We study the connection of this property with strongly weakly compactly generated Banach spaces and its stability under subspaces, quotients and \({\ell^p}\) -sums. We extend a result of Frankiewicz and Plebanek by proving that property (K) is preserved by \({\ell^1}\) -sums of less than \({\mathfrak{p}}\) summands. Without any cardinality restriction, we show that property (K) is stable under \({\ell^p}\) -sums for \({1 < p < \infty}\) .AbstractA Banach space X is said to have property (K) if every w*-convergent sequence in X* admits a convex block subsequence which converges with respect to the Mackey topology. We study the connection of this property with strongly weakly compactly generated Banach spaces and its stability under subspaces, quotients and \({\ell^p}\) -sums. We extend a result of Frankiewicz and Plebanek by proving that property (K) is preserved by \({\ell^1}\) -sums of less than \({\mathfrak{p}}\) summands. Without any cardinality restriction, we show that property (K) is stable under \({\ell^p}\) -sums for \({1 < p < \infty}\) .XwX \({\ell^p}\) \({\ell^p}\) \({\ell^1}\) \({\ell^1}\) \({\mathfrak{p}}\) \({\mathfrak{p}}\) \({\ell^p}\) \({\ell^p}\) \({1 < p < \infty}\) \({1 < p < \infty}\)