We prove that any real or complex countably generated algebra has a complete locally convex topology making it a topological algebra. Assuming the continuum hypothesis, it is the best possible result expressed in terms of the cardinality of a set of generators. This result is a corollary to a theorem stating that a free algebra provided with the maximal locally convex topology is a topological algebra if and only if the number of variables is at most countable. As a byproduct we obtain an example of a semitopological (non-topological) algebra with every commutative subalgebra topological.
@article{bwmeta1.element.bwnjournal-article-smv112i1p83bwm, author = {W. \.Zelazko}, title = {On topologization of countably generated algebras}, journal = {Studia Mathematica}, volume = {108}, year = {1994}, pages = {83-88}, zbl = {0832.46042}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-smv112i1p83bwm} }
Żelazko, W. On topologization of countably generated algebras. Studia Mathematica, Tome 108 (1994) pp. 83-88. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-smv112i1p83bwm/
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