Topologically Invertible Elements and Topological Spectrum
Mati Abel, W. Żelazko · Bulletin of the Polish Academy of Sciences Mathematics · 2006
Properties of topologically invertible elements and the topological spectrum of elements in unital semitopological algebras are studied. It is shown that the inversion $x\mapsto x^{-1}$ is continuous in every invertive Fréchet algebra, and singly generate