Sunto
Consideriamo il seguente problema: determinare quando certe algebre di Banach di funzioni sul toro o sugli interi, che sono generate dai loro idempotenti, contengono sottoalgebre chiuse che non hanno tale proprietà.
Consideriamo inoltre altre proprietà speciali che tali sottoalgebre possono possedere.
Summary
We consider the question of when certain Banach algebras on the circle group or the integers, which themselves are the closed span of their idempotents, have closed subalgebras which fail to have this property. We also consider what other special properties such subalgebras may have.
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References
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(Conferenza tenuta il 15 giugno 1978)
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Bachelis, G.F. Some approximation problems in harmonic analysis. Seminario Mat. e. Fis. di Milano 48, 119–123 (1978). https://doi.org/10.1007/BF02925566
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DOI: https://doi.org/10.1007/BF02925566