How weak is weak extent?

2000/06/26 by Mikhail Matveev, Matveev, Mikhail
Mathematics · #FOS: Mathematics #General Topology (math.GN) #math.GN

paper · pdf · doi:10.48550/arxiv.math/0006198

arxiv created 2000/06/26 · arxiv updated 2009/11/30

Abstract

A space X is star-Lindelof provided for every open cover U there is a finite subset A of X such that St(A,U)=X. We show that a Tychonoff star-Lindelof space can have arbitraryly big extent while the extent of a normal star-Lindelof space can not be greater than c.

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