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Three-space problems for polynomial properties in Banach spaces
by
Francisco Arranz
Departamento de Matemáticas, Universidad de Extremadura
Coauthors: Jesus M.F. Castillo, Ricardo Garcia
The purpuse of this talk is to answer some questions posed in the monograph [3, Appendix 4.20]. Precisely, the authors complain there the lack of "three-space" results for polynomial properties. Let us recall that if P and Q are two properties of Banach spaces stable by isomorphisms then a Banach space X is said to have the P-by-Q property if it admits a subspace Y with property P so that X/Y has property Q.
A property P is said to be a three-space property if P-by-Q implies P. If a Banach space has simultaneously properties P and Q we shall say that it has the property P&Q property. It will be shown in this talk that the following are not 3-space properties:
The polynomial (RP) of Aron, Choi and Llavona.
The polynomial Schur property of Carne, Cole and Gamelin.
The polynomial Dunford-Pettis property of Gonzalez and Gutierrez.
All this together with other results exposed in the talk, provides a fairly complete catalog of the current state of 3-space problems related to polynomial properties. In the last part of the talk we observe that all couterexamples to the 3-space for properties Mn have in common the presence of copies of l1. On the other hand, no available method can produce a counterexample made with reflexive spaces. In between, we shall consider "not containing l1" as a weak form of reflexivity and will tackle the 3-space problem for the property M2
REFERENCES
[1] R. Aron, Y. Choi and J. Llavona, Estimates by polynomials, Bull. Austral. Math. Soc. 52 (3)(1995), 475-486.
[2] T. Carne, B. Cole and T. Gamelin, A uniform algebra of analytic functions an on Banach space, Trans. Amer. Math. Soc. 314 (1989), 639-659.
[3] J. M. F. Castillo, M. González, Three-space problems in Banach spaces theory, Lecture Notes in Math. 1667, Springer-Verlag, Berlin-Heidelberg-New York, 1997.
[4] W. B. Johnson and J. Lindenstrauss, Some remarks on weakly compactly generated Banach space, Israel J. Math. 17 (1974), 219-230.
[5] N. J. Kalton and N. T. Peck, Twisted sums of sequence spaces and three space problem, Trans. Amer. Math. Soc. 255 (1979), 1-30.
(T)
Date received: April 17, 2000
Copyright © 2000 by the author(s). The author(s) of this document and the organizers of the conference have granted their consent to include this abstract in Atlas Conferences Inc. Document # caey-81.