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Uncountable ω-limit sets with isolated points

Chris Good, Brian E. Raines, Rolf Suabedissen (2009)

Fundamenta Mathematicae

We give two examples of tent maps with uncountable (as it happens, post-critical) ω-limit sets, which have isolated points, with interesting structures. Such ω-limit sets must be of the form C ∪ R, where C is a Cantor set and R is a scattered set. Firstly, it is known that there is a restriction on the topological structure of countable ω-limit sets for finite-to-one maps satisfying at least some weak form of expansivity. We show that this restriction does not hold if the ω-limit set is uncountable....

Uncountably many wild knots whose cyclic branched covering are S3.

José María Montesinos-Amilibia (2003)

Revista Matemática Complutense

There is a disk in S3 whose interior is PL embedded and whose boundary has a tame Cantor set of locally wild points, such that the n-fold cyclic coverings of S3 branched over the boundary of the disk are all S3. An uncountable set of inequivalent wild knots with these properties is exhibited.

Undetermined sets of point-open games

Janusz Pawlikowski (1994)

Fundamenta Mathematicae

We show that a set of reals is undetermined in Galvin's point-open game iff it is uncountable and has property C", which answers a question of Gruenhage.

Une méthode de construction squelette par squelette dans les espaces paracompacts

Robert Cauty (1973)

Annales de l'institut Fourier

Dans cet article, on développe, pour les espaces paracompacts, une méthode de construction analogue à la construction par récurrence sur les squelettes dans les C W -complexes. On l’applique à des problèmes de prolongement ainsi qu’à l’existence de fonctions canoniques dans les nerfs de recouvrements fermés.

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