Hostname: page-component-78c5997874-mlc7c Total loading time: 0 Render date: 2024-11-10T14:36:03.308Z Has data issue: false hasContentIssue false

FLAT SETS, p-GENERATING AND FIXING c0 IN THE NONSEPARABLE SETTING

Published online by Cambridge University Press:  09 October 2009

M. FABIAN*
Affiliation:
Mathematical Institute of the Czech Academy of Sciences, Žitná 25, 115 67, Prague 1, Czech Republic (email: fabian@math.cas.cz)
A. GONZÁLEZ
Affiliation:
Instituto de Matemática Pura y Aplicada, Universidad Politécnica de Valencia, C/Vera, s/n. 46022 Valencia, Spain (email: algoncor@doctor.upv.es)
V. ZIZLER
Affiliation:
Mathematical Institute of the Czech Academy of Sciences, Žitná 25, 115 67, Prague 1, Czech Republic (email: zizler@math.cas.cz)
*
For correspondence; e-mail: fabian@math.cas.cz
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

We define asymptotically p-flat and innerly asymptotically p-flat sets in Banach spaces in terms of uniform weak* Kadec–Klee asymptotic smoothness, and use these concepts to characterize weakly compactly generated (Asplund) spaces that are c0(ω1)-generated or p(ω1)-generated, where p∈(1,). In particular, we show that every subspace of c0(ω1) is c0(ω1)-generated and every subspace of p(ω1) is p(ω1)-generated for every p∈(1,). As a byproduct of the technology of projectional resolutions of the identity we get an alternative proof of Rosenthal’s theorem on fixing c0(ω1).

Type
Research Article
Copyright
Copyright © Australian Mathematical Publishing Association Inc. 2009

Footnotes

The first author was supported by grants AVOZ 101 905 03 and IAA 100 190 610 and the Universidad Politécnica de Valencia. The second author was supported in a Grant CONACYT of the Mexican Government. The third author was supported by grants AVOZ 101 905 03 and GAČR 201/07/0394.

References

[1]Diestel, J., Sequence and Series in Banach Spaces, Graduate Texts in Mathematics, 92 (Springer, New York, 1984).Google Scholar
[2]Fabian, M., Differentiability of Convex Functions and Topology-Weak Asplund Spaces (John Wiley and Sons, New York, 1997).Google Scholar
[3]Fabian, M., Habala, P., Hájek, P., Montesinos, V., Pelant, J. and Zizler, V., Functional Analysis and Infinite Dimensional Geometry, Canadian Mathematical Society Books in Mathematics, 8 (Springer, New York, 2001).CrossRefGoogle Scholar
[4]Fabian, M., Godefroy, G., Hájek, P., Zizler, V., Fabian, M., Godefroy, G., Hájek, P. and Zizler, V., ‘Hilbert-generated spaces’, J. Funct. Anal. 200 (2003), 301323.CrossRefGoogle Scholar
[5]Fabian, M., Godefroy, G., Montesinos, V. and Zizler, V., ‘Inner characterization of weakly compactly generated Banach spaces and their relatives’, J. Math. Anal. Appl. 297 (2004), 419455.CrossRefGoogle Scholar
[6]Fabian, M., Montesinos, V. and Zizler, V., ‘Weak compactness and sigma-Asplund generated Banach spaces’, Studia Math. 181 (2007), 125152.CrossRefGoogle Scholar
[7]Godefroy, G., Kalton, N. and Lancien, G., ‘Subspaces of c 0(ℕ) and Lipschitz isomorphisms’, Geom. Funct. Anal. 10 (2000), 798820.CrossRefGoogle Scholar
[8]Hájek, P., Montesinos, V., Vanderwerff, J. and Zizler, V., Biorthogonal Systems in Banach spaces, Canadian Mathematical Society Books in Mathematics (Canadian Mathematical Society, Springer Verlag, 2007).Google Scholar
[9]John, K. and Zizler, V., ‘Some notes on Markushevich bases in weakly compactly generated Banach spaces’, Compos. Math. 35 (1977), 113123.Google Scholar
[10]Lancien, G., ‘On uniformly convex and uniformly Kadec–Klee renormings’, Serdica Math. J. 21 (1995), 118.Google Scholar
[11]Milman, V. D., ‘Geometric theory of Banach spaces II. Geometry of the unit ball’ [in Russian], Uspekhi Mat. Nauk. 26(6 (162)) (1971), 73–149; Engl. Transl. Russian Math. Surveys 26 (1971), 6, 79–163..Google Scholar
[12]Rosenthal, H. P., ‘On relatively disjoint families of measures, with some applications to Banach space theory’, Studia Math. 37 (1970), 1330.Google Scholar
[13]Rosenthal, H. P., ‘The heredity problem for weakly compactly generated Banach spaces’, Compositio Math. 28 (1974), 83111.Google Scholar