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Joint spectra and restricted Gelfand transform. (English) Zbl 07342826

Summary: By considering joint spectrum on infinite and non-commutative subsets of a locally convex Waelbroeck algebra \(W\) we show that the phenomenon called Spectral Mapping Theorem is related with the existence and extensibility of multiplicative functionals on subalgebras generated by subsets \(S\subset W\). The corresponding multiplicative functionals are characterized by the property that \(\ker\varphi\) generates in \(W\) a proper left or right ideal. For a subalgebra \(B\subset W\) which admits this type of functionals we define the restricted Gelfand transform and we provide an interpretation of the related joint spectrum.

MSC:

47A13 Several-variable operator theory (spectral, Fredholm, etc.)
47A60 Functional calculus for linear operators
46H30 Functional calculus in topological algebras
Full Text: DOI

References:

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