Multipliers with closed range on commutative semisimple Banach algebras

• Autorzy: A. Ülger
• Języki publikacji: EN

Abstrakty

EN

Let A be a commutative semisimple Banach algebra, Δ(A) its Gelfand spectrum, T a multiplier on A and T̂ its Gelfand transform. We study the following problems. (a) When is δ(T) = inf{|T̂(f)|: f ∈ Δ(A), T̂(f) ≠ 0} > 0? (b) When is the range T(A) of T closed in A and does it have a bounded approximate identity? (c) How to characterize the idempotent multipliers in terms of subsets of Δ(A)?

Kategorie tematyczne

• 47B48: Operators on Banach algebras
• 46J10: Banach algebras of continuous functions, function algebras
• 43A22: Homomorphisms and multipliers of function spaces on groups, semigroups, etc.

• Wydawca: Institute of Mathematics Polish Academy of Sciences
• Czasopismo: Studia Mathematica
• Rocznik: 2002
• Tom: 153
• Numer: 1
• Strony: 59-80

Daty

wydano

2002

Twórcy

autor

A. Ülger

• Department of Mathematics, Koc University, Fener Yolu, 80910, Sariyer, Istanbul, Turkey

Identyfikatory

DOI

10.4064/sm153-1-5