Free topological groups on metrizable spaces and inductive limits
β Scribed by Vladimir Pestov; Kohzo Yamada
- Publisher
- Elsevier Science
- Year
- 1999
- Tongue
- English
- Weight
- 107 KB
- Volume
- 98
- Category
- Article
- ISSN
- 0166-8641
No coin nor oath required. For personal study only.
β¦ Synopsis
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 separable. In the non-Abelian case, for a metrizable X the following are equivalent: (i) the free topological group F (X) is the inductive limit of the sequence {F n (X): n β N}; (ii) X is either locally compact separable or discrete.
π SIMILAR VOLUMES
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 n
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