Title of article :
Compact spaces generated by retractions
Author/Authors :
Kubi?، نويسنده , , Wies?aw، نويسنده ,
Issue Information :
دوماهنامه با شماره پیاپی سال 2006
Pages :
14
From page :
3383
To page :
3396
Abstract :
We study compact spaces which are obtained from metric compacta by iterating the operation of inverse limit of continuous sequences of retractions. This class, denoted by R , has been introduced in [M. Burke, W. Kubiś, S. Todorčević, Kadec norms on spaces of continuous functions, http://arxiv.org/abs/math.FA/0312013]. Allowing continuous images in the definition of class R , one obtains a strictly larger class, which we denote by R C . We show that every space in class R C is either Corson compact or else contains a copy of the ordinal segment ω 1 + 1 . This improves a result of Kalenda from [O. Kalenda, Embedding of the ordinal segment [ 0 , ω 1 ] into continuous images of Valdivia compacta, Comment. Math. Univ. Carolin. 40 (4) (1999) 777–783], where the same was proved for the class of continuous images of Valdivia compacta. We prove that spaces in class R do not contain cutting P-points (see the definition below), which provides a tool for finding spaces in R C ∖ R . Finally, we study linearly ordered spaces in class R C . We prove that scattered linearly ordered compacta belong to R C and we characterize those ones which belong to R . We show that there are only 5 types (up to order isomorphism) of connected linearly ordered spaces in class R and all of them are Valdivia compact. Finally, we find a universal pre-image for the class of all linearly ordered Valdivia compacta.
Keywords :
Valdivia compact space , Inverse sequence , Corson compact , Retraction , Linearly ordered compact space
Journal title :
Topology and its Applications
Serial Year :
2006
Journal title :
Topology and its Applications
Record number :
1581026
Link To Document :
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