On the extent of star countable spaces


Autoria(s): ALAS, Ofelia T.; JUNQUEIRA, Lucia R.; MILL, Jan van; TKACHUK, Vladimir V.; WILSON, Richard G.
Contribuinte(s)

UNIVERSIDADE DE SÃO PAULO

Data(s)

20/10/2012

20/10/2012

2011

Resumo

For a topological property P, we say that a space X is star Pif for every open cover Uof the space X there exists Y aS, X such that St(Y,U) = X and Y has P. We consider star countable and star Lindelof spaces establishing, among other things, that there exists first countable pseudocompact spaces which are not star Lindelof. We also describe some classes of spaces in which star countability is equivalent to countable extent and show that a star countable space with a dense sigma-compact subspace can have arbitrary extent. It is proved that for any omega (1)-monolithic compact space X, if C (p) (X)is star countable then it is Lindelof.

Identificador

CENTRAL EUROPEAN JOURNAL OF MATHEMATICS, v.9, n.3, p.603-615, 2011

1895-1074

http://producao.usp.br/handle/BDPI/30680

10.2478/s11533-011-0018-y

http://dx.doi.org/10.2478/s11533-011-0018-y

Idioma(s)

eng

Publicador

VERSITA

Relação

Central European Journal of Mathematics

Direitos

restrictedAccess

Copyright VERSITA

Palavras-Chave #Lindelof property #Extent #Star properties #Star countable spaces #Star Lindelof spaces #Pseudocompact spaces #Countably compact spaces #Function spaces #kappa-monolithic spaces #Products of ordinals #P-spaces #Metalindelof spaces #Discrete subspaces #Open expansions #COVERING PROPERTIES #WEAK #Mathematics
Tipo

article

original article

publishedVersion