Resumen de A note on a theorem of James
Let (en)n=1∞ be the unit basis of the Banach space c0. In this paper we prove that, if X is a separable Banach space, there is a closed bounded absolutely convex subset B of c0 which has the following properties: (1) ej ∈ B, j=1,2,...′, and (en)n=1∞ is a monotone shrinking basis of (c0)B. (2) (c0)B has a topological complement Z in ((c0)B)** which is weak*-closed and isometric to X*. (3) The projection from ((c0)B)** onto Z along (c0)B has norm one. © 2011 Springer-Verlag.
