Open AccessInvariance and normality of projections in the dual of Banach algebras
Author(s) -
A.L. Barrenechea,
Carlos C. Peña
Publication year - 2021
Publication title -
new zealand journal of mathematics
Language(s) - English
Resource type - Journals
eISSN - 1179-4984
pISSN - 1171-6096
DOI - 10.53733/132
Subject(s) - mathematics , invariant (physics) , projection (relational algebra) , dual (grammatical number) , pure mathematics , bounded function , approximation property , banach space , algebra over a field , mathematical analysis , algorithm , art , literature , mathematical physics
We study the classes of invariant and natural projections in the dual of a Banach algebra $A$. These type of projections are relevant by their connections with the existence problem of bounded approximate identities in closed ideals of Banach algebras. It is known that any invariant projection is a natural projection. In this article we consider the issue of when a natural projection is an invariant projection.