ArticleOriginal scientific text
Title
A relatively free topological group that is not varietal free
Authors 1, 2
Affiliations
- School of Mathematical and Computing Sciences, Victoria University of Wellington, P.O. Box 600, Wellington, New Zealand
- Department of Mathematical Sciences, Faculty of Science, Ehime University, Matsuyama 790, Japan
Abstract
Answering a 1982 question of Sidney A. Morris, we construct a topological group G and a subspace X such that (i) G is algebraically free over X, (ii) G is relatively free over X, that is, every continuous mapping from X to G extends to a unique continuous endomorphism of G, and (iii) G is not a varietal free topological group on X in any variety of topological groups.
Keywords
relatively free topological group, variety of topological groups, free zero-dimensional topological group, varietal free topological group
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