ON UNIFORMLY GATEAUX DIFFERENTIABLE NORMS IN C(K)

Citation
A. Molto et S. Troyanski, ON UNIFORMLY GATEAUX DIFFERENTIABLE NORMS IN C(K), Mathematika, 41(82), 1994, pp. 233-238
Citations number
7
Categorie Soggetti
Mathematics, General",Mathematics
Journal title
ISSN journal
00255793
Volume
41
Issue
82
Year of publication
1994
Part
2
Pages
233 - 238
Database
ISI
SICI code
0025-5793(1994)41:82<233:OUGDNI>2.0.ZU;2-7
Abstract
It is proved that C(K) has no equivalent uniformly Gateaux differentia ble norm (UGD) when K is an uncountable separable scattered compact sp ace. This result is applied to obtain an example of scattered compact K such that K-m = null set and C(K) has no UGD renorming. In the last few years lots of remarkable results concerning renormings of C(K), wh en K is a scattered compact have been obtained. These results are pres ented in [DGZ, Chapter VIII and [H]. We will only mention that it foll ows from results of Deville [D] and Haydon-Rogers [HR] that if K is sc attered compact and K-(omega 1)= null set then C(K) admits an equivale nt locally uniformly rotund norm whose dual norm is locally uniformly rotund. The aim of this paper is to characterize the separable scatter ed compact spaces K for which C(K) has an equivalent uniformly Gateaux differentiable (UGD for short) norm.