Spectrum of commutative Banach algebras and isomorphism of C*-algebras related to locally compact groups
Let A be a semisimple commutative regular tauberian Banach algebra with spectrum . In this paper, we study the norm spectra of elements of and present some applications. In particular, we characterize the discreteness of in terms of norm spectra. The algebra A is said to have property (S) if, for all , φ has a nonempty norm spectrum. For a locally compact group G, let denote the C*-algebra generated by left translation operators on and denote the discrete group G. We prove that the Fourier...