Displaying similar documents to “Lindelöf property and the iterated continuous function spaces”

Countably metacompact spaces in the constructible universe

Paul Szeptycki (1993)

Fundamenta Mathematicae

Similarity:

We present a construction from ♢* of a first countable, regular, countably metacompact space with a closed discrete subspace that is not a G δ . In addition some nonperfect spaces with σ-disjoint bases are constructed.

Forcing countable networks for spaces satisfying R ( X ω ) = ω

István Juhász, Lajos Soukup, Zoltán Szentmiklóssy (1996)

Commentationes Mathematicae Universitatis Carolinae

Similarity:

We show that all finite powers of a Hausdorff space X do not contain uncountable weakly separated subspaces iff there is a c.c.c poset P such that in V P X is a countable union of 0 -dimensional subspaces of countable weight. We also show that this theorem is sharp in two different senses: (i) we cannot get rid of using generic extensions, (ii) we have to consider all finite powers of X .

Finite union of H-sets and countable compact sets

Sylvain Kahane (1993)

Colloquium Mathematicae

Similarity:

In [2], D. E. Grow and M. Insall construct a countable compact set which is not the union of two H-sets. We make precise this result in two directions, proving such a set may be, but need not be, a finite union of H-sets. Descriptive set theory tools like Cantor-Bendixson ranks are used; they are developed in the book of A. S. Kechris and A. Louveau [6]. Two proofs are presented; the first one is elementary while the second one is more general and useful. Using the last one I prove in...

On D-dimension of metrizable spaces

Wojciech Olszewski (1991)

Fundamenta Mathematicae

Similarity:

For every cardinal τ and every ordinal α, we construct a metrizable space M α ( τ ) and a strongly countable-dimensional compact space Z α ( τ ) of weight τ such that D ( M α ( τ ) ) ≤ α , D ( Z α ( τ ) ) ≤ α and each metrizable space X of weight τ such that D(X) ≤ α is homeomorphic to a subspace of M α ( τ ) and to a subspace of Z α + 1 ( τ ) .