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arXiv · 0708.3126

Semilattice Structures of Spreading Models

Denny H. Leung·Wee-Kee Tang
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Abstract

Given a Banach space X, denote by SP_{w}(X) the set of equivalence classes of spreading models of X generated by normalized weakly null sequences in X. It is known that SP_{w}(X) is a semilattice, i.e., it is a partially ordered set in which every pair of elements has a least upper bound. We show that every countable semilattice that does not contain an infinite increasing sequence is order isomorphic to SP_{w}(X) for some separable Banach space X.

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Denny H. Leung, Wee-Kee Tang. 2007-08-23. Semilattice Structures of Spreading Models. https://arxiv.org/abs/0708.3126

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