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A dimension raising hereditary shape equivalence

Jan Dijkstra (1996)

Fundamenta Mathematicae

We construct a hereditary shape equivalence that raises transfinite inductive dimension from ω to ω+1. This shows that ind and Ind do not admit a geometric characterisation in the spirit of Alexandroff's Essential Mapping Theorem, answering a question asked by R. Pol.

A dimensional property of Cartesian product

Michael Levin (2013)

Fundamenta Mathematicae

We show that the Cartesian product of three hereditarily infinite-dimensional compact metric spaces is never hereditarily infinite-dimensional. It is quite surprising that the proof of this fact (and this is the only proof known to the author) essentially relies on algebraic topology.

A factorization theorem for the transfinite kernel dimension of metrizable spaces

M. Charalambous (1998)

Fundamenta Mathematicae

We prove a factorization theorem for transfinite kernel dimension in the class of metrizable spaces. Our result in conjunction with Pasynkov's technique implies the existence of a universal element in the class of metrizable spaces of given weight and transfinite kernel dimension, a result known from the work of Luxemburg and Olszewski.

A fixed-point anomaly in the plane

Charles L. Hagopian, Janusz R. Prajs (2005)

Fundamenta Mathematicae

We define an unusual continuum M with the fixed-point property in the plane ℝ². There is a disk D in ℝ² such that M ∩ D is an arc and M ∪ D does not have the fixed-point property. This example answers a question of R. H. Bing. The continuum M is a countable union of arcs.

A formula for calculation of metric dimension of converging sequences

Ladislav, Jr. Mišík, Tibor Žáčik (1999)

Commentationes Mathematicae Universitatis Carolinae

Converging sequences in metric space have Hausdorff dimension zero, but their metric dimension (limit capacity, entropy dimension, box-counting dimension, Hausdorff dimension, Kolmogorov dimension, Minkowski dimension, Bouligand dimension, respectively) can be positive. Dimensions of such sequences are calculated using a different approach for each type. In this paper, a rather simple formula for (lower, upper) metric dimension of any sequence given by a differentiable convex function, is derived....

A hit-and-miss topology for 2 X , Cₙ(X) and Fₙ(X)

Benjamín Espinoza, Verónica Martínez-de-la-Vega, Jorge M. Martínez-Montejano (2009)

Colloquium Mathematicae

A hit-and-miss topology ( τ H M ) is defined for the hyperspaces 2 X , Cₙ(X) and Fₙ(X) of a continuum X. We study the relationship between τ H M and the Vietoris topology and we find conditions on X for which these topologies are equivalent.

A metrizable completely regular ordered space

Hans-Peter A. Künzi, Stephen W. Watson (1994)

Commentationes Mathematicae Universitatis Carolinae

We construct a completely regular ordered space ( X , 𝒯 , ) such that X is an I -space, the topology 𝒯 of X is metrizable and the bitopological space ( X , 𝒯 , 𝒯 ) is pairwise regular, but not pairwise completely regular. (Here 𝒯 denotes the upper topology and 𝒯 the lower topology of X .)

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