Scattered compact sets in continuous images of Cech-complete spaces
Abstract
Assume hat a functionally Hausdorff space X is a continuous image of a Cech complete space P with Lindel\"of number l(P)< c. Then the following conditions are equivalent: (i) every compact subset of X is scattered, (ii) for every continuous map f:X Y to a functionally Hausdorff space Y the image f(X) has cardinality |f(X)| \l(P),(Y)\, (iii) no continuous map f:X[0,1] is surjective. Also we prove the equivalence of the conditions: (a) ω1< b, (b) a K-analytic space X (with a unique non-isolated point) is countable if and only if every compact subset of X is countable.
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