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Self-induced compactness in Banach spaces

Published online by Cambridge University Press:  14 November 2011

P. G. Casazza
Affiliation:
Department of Mathematics, University of Missouri-Columbia, Columbia, Mo 65211, U.S.A. e-mail: Pete@casazza.cs.missouri.edu
H. Jarchow
Affiliation:
Mathematisches Institut, Universität Zürich, CH 8057 Zürich, Switzerland e-mail: jarchow@math.unizh.ch

Extract

We consider the question: is every compact set in a Banach space X contained in the closed unit range of a compact (or even approximable) operator on X? We give large classes of spaces where the question has an affirmative answer, but observe that it has a negative answer, in general, for approximable operators. We further construct a Banach space failing the bounded compact approximation property, though all of its duals have the metric compact approximation property.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 1996

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