Displaying similar documents to “A relatively free topological group that is not varietal free”

Open subgroups of free topological groups

Jeremy Brazas (2014)

Fundamenta Mathematicae

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The theory of covering spaces is often used to prove the Nielsen-Schreier theorem, which states that every subgroup of a free group is free. We apply the more general theory of semicovering spaces to obtain analogous subgroup theorems for topological groups: Every open subgroup of a free Graev topological group is a free Graev topological group. An open subgroup of a free Markov topological group is a free Markov topological group if and only if it is disconnected.

On Schwartz groups

L. Außenhofer, M. J. Chasco, X. Domínguez, V. Tarieladze (2007)

Studia Mathematica

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We introduce a notion of a Schwartz group, which turns out to be coherent with the well known concept of a Schwartz topological vector space. We establish several basic properties of Schwartz groups and show that free topological Abelian groups, as well as free locally convex spaces, over hemicompact k-spaces are Schwartz groups. We also prove that every hemicompact k-space topological group, in particular the Pontryagin dual of a metrizable topological group, is a Schwartz group. ...