English

Continuous bilinear maps on Banach $\star$-algebras

Functional Analysis 2022-02-04 v1

Abstract

Let AA be a unital Banach \star-algebra with unity 11, XX be a Banach space and ϕ:A×AX\phi : A \times A \to X be a continuous bilinear map. We characterize the structure of ϕ\phi where it satisfies any of the following properties: a,bA,ab=z(ab=z)ϕ(a,b)=ϕ(z,1)(ϕ(a,b)=ϕ(z,1));a,b \in A, \,\,\, a b^\star = z \, \,(a^\star b=z)\Rightarrow \phi ( a , b^\star ) = \phi ( z, 1 ) \, \, (\phi ( a^\star , b) = \phi ( z, 1 )); a,bA,ab=z(ab=z)ϕ(a,b)=ϕ(1,z)(ϕ(a,b)=ϕ(1,z)),a,b \in A, \,\,\, a b^\star = z \, \, (a^\star b=z)\Rightarrow \phi ( a , b^\star ) = \phi ( 1, z ) \, \, (\phi ( a^\star , b) = \phi ( 1, z )), where zAz\in A is fixed.

Keywords

Cite

@article{arxiv.2202.01766,
  title  = {Continuous bilinear maps on Banach $\star$-algebras},
  author = {Behrooz Fadaee},
  journal= {arXiv preprint arXiv:2202.01766},
  year   = {2022}
}

Comments

5 pages

R2 v1 2026-06-24T09:18:32.999Z