A characterization of multiplicative linear functionals in complex Banach algebras
نویسندگان
چکیده
منابع مشابه
Almost multiplicative linear functionals and approximate spectrum
We define a new type of spectrum, called δ-approximate spectrum, of an element a in a complex unital Banach algebra A and show that the δ-approximate spectrum σ_δ (a) of a is compact. The relation between the δ-approximate spectrum and the usual spectrum is investigated. Also an analogue of the classical Gleason-Kahane-Zelazko theorem is established: For each ε>0, there is δ>0 such that if ϕ is...
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متن کاملalmost multiplicative linear functionals and approximate spectrum
we define a new type of spectrum, called δ-approximate spectrum, of an element a in a complex unital banach algebra a and show that the δ-approximate spectrum σ_δ (a) of a is compact. the relation between the δ-approximate spectrum and the usual spectrum is investigated. also an analogue of the classical gleason-kahane-zelazko theorem is established: for each ε>0, there is δ>0 such that if ϕ is...
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ژورنال
عنوان ژورنال: Studia Mathematica
سال: 1968
ISSN: 0039-3223,1730-6337
DOI: 10.4064/sm-30-1-83-85