Proceedings of the American Mathematical Society

Author(s): Stanisław Prus
Journal: Proc. Amer. Math. Soc. 138 (2010), 225-234.
MSC (2000): Primary 46B20
Posted: August 27, 2009
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Abstract: A construction of separated sequences in the unit sphere of a Banach space is given. If a space

admits an equivalent nearly uniformly convex norm or

is not finitely representable in

, then lower bounds for separation constants of sequences are strictly greater than 1. This gives a partial answer to a problem posed by J. Diestel.

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Retrieve articles in Proceedings of the American Mathematical Society with MSC (2000): 46B20

Stanisław Prus
Affiliation: Institute of Mathematics, M. Curie-Skłodowska University, 20-031 Lublin, Poland
Email: bsprus@golem.umcs.lublin.pl

DOI: 10.1090/S0002-9939-09-10024-2
PII: S 0002-9939(09)10024-2
Keywords: Separation constant, Diestel's problem, spreading model
Received by editor(s): February 17, 2009,
Received by editor(s) in revised form: April 20, 2009
Posted: August 27, 2009
Communicated by: Nigel J. Kalton
Copyright of article: Copyright 2009, American Mathematical Society
The copyright for this article reverts to public domain after 28 years from publication.

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