English

Vector-valued spectra of Banach algebra valued continuous functions

Functional Analysis 2015-12-31 v2

Abstract

Given a compact space XX, a commutative Banach algebra AA, and an AA-valued function algebra A\mathscr{A} on XX, the notions of vector-valued spectrum of functions fAf\in\mathscr{A} are discussed. The AA-valued spectrum SPA(f)\vec{SP}_A(f) of every fAf\in\mathscr{A} is defined in such a way that f(X)SPA(f)f(X) \subset \vec{SP}_A(f). Utilizing the AA-characters introduced in (M. Abtahi, \textit{Vector-valued characters on vector-valued function algebras}, \texttt{arXiv:1509.09215 [math.FA]}), it is proved that \vec{SP}_A(f) = \{\Psi(f):\text{\Psiisan is an Acharacterof-character of \mathscr{A}}\}. For the so-called natural AA-valued function algebras, such as C(X,A)C(X,A) and Lip(X,A)Lip(X,A), we see that SPA(f)=f(X)\vec{SP}_A(f)=f(X). When A=CA = \mathbb{C}, Banach AA-valued function algebras reduce to Banach function algebras, AA-characters reduce to characters, and AA-valued spectrums reduce to usual spectrums.

Cite

@article{arxiv.1510.06641,
  title  = {Vector-valued spectra of Banach algebra valued continuous functions},
  author = {Mortaza Abtahi and Sara Farhangi},
  journal= {arXiv preprint arXiv:1510.06641},
  year   = {2015}
}
R2 v1 2026-06-22T11:26:41.125Z