Let X denote a compact &spemd space with characteristic (~,n). .ks is we&known, the space I?(cY) consisting of the ordinals not excse&ng Q &h the htefvaf top(&)gy has ch;arwteristiz r&n) if and only if &a, < cy < (? l (n f-1). It seems natural to regard the xdir : spaces as "minimal"' dispersed spac
Free topological groups of spaces and their subspaces
β Scribed by Ol'ga V. Sipacheva
- Publisher
- Elsevier Science
- Year
- 2000
- Tongue
- English
- Weight
- 266 KB
- Volume
- 101
- Category
- Article
- ISSN
- 0166-8641
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β¦ Synopsis
We prove that if X is a Tychonoff topological space, Y a subspace of X, and every bounded continuous pseudometric on Y can be extended to a continuous pseudometric on X, then the free topological group F M (Y ) coincides with the topological subgroup of F M (X) generated by Y . For this purpose, a new description for the topology of a free topological group in terms of continuous pseudometrics and group seminorms is given. It follows from what has been shown by UspenskiΘ that this result implies the Weil completeness of F M (X) for any DieudonnΓ© complete X. It is also proved that if dim X = 0, then ind F M (X) = 0.
π SIMILAR VOLUMES
It is known that the free topological group over the Tychonoff space X, denoted F (X), is a Pspace if and only if X is a P -space. This article is concerned with the question of whether one can characterize when F (X) is a weak P -space, that is, a space where all countable subsets are closed. Our m
We prove that for a metrizable space X the following are equivalent: (i) the free Abelian topological group A(X) is the inductive limit of the sequence {A n (X): n β N}, where A n (X) is formed by all words of reduced length n; (ii) X is locally compact and the set of all non-isolated points of X is