منابع مشابه
Characterizations of almost transitive superreflexive Banach spaces
Almost transitive superreflexive Banach spaces have been considered in [7] (see also [4] and [6]), where it is shown that such spaces are uniformly convex and uniformly smooth. We prove that convex transitive Banach spaces are either almost transitive and superreflexive (hence uniformly smooth) or extremely rough. The extreme roughness of a Banach space X means that, for every element u in the ...
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In this paper we continue the study of central subspaces initiated in [2] and its infinite version called almost constrained subspaces. We are interested in studying situations where these intersection properties of balls lead to the existence of a linear projection of norm one. We show that every finite dimensional subspace is a central subspace only in Hilbert spaces. By considering direct su...
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We prove that the spaces `p, 1 < p < ∞, p 6= 2, and all infinite-dimensional subspaces of their quotient spaces do not admit equivalent almosttransitive renormings. This answers a problem posed by Deville, Godefroyand Zizler in 1993. We obtain this as a consequence of a new property ofalmost transitive spaces with a Schauder basis, namely we prove that in suchspaces the unit...
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ژورنال
عنوان ژورنال: Indagationes Mathematicae (Proceedings)
سال: 1968
ISSN: 1385-7258
DOI: 10.1016/s1385-7258(68)50021-0