English

Jointly separating maps between vector-valued function spaces

Functional Analysis 2018-05-01 v1

Abstract

Let XX and YY be compact Hausdorff spaces, EE and FF be real or complex Banach spaces, and A(X,E)A(X,E) be a subspace of C(X,E)C(X,E). In this paper we study linear operators S,T:A(X,E)\loC(Y,F)S,T: A(X,E) \lo C(Y,F) which are jointly separating, in the sense that \coz(f)\coz(g)=\coz(f) \cap \coz(g) = \emptyset implies that \coz(Tf)\coz(Sg)=\coz(Tf) \cap \coz(Sg)=\emptyset. Here \coz()\coz(\cdot) denotes the cozero set of a function. We characterize the general form of such maps between certain class of vector-valued (as well as scalar-valued) spaces of continuous functions including spaces of vector-valued Lipschitz functions, absolutely continuous functions and continuously differentiable functions. The results can be applied for a pair T:A(X)\loA(X)T:A(X) \lo A(X) and S:A(X,E)\loA(X,E)S:A(X,E) \lo A(X,E) of linear operators, where A(X)A(X) is a regular Banach function algebra on XX, such that fg=0f\cdot g=0 implies TfSg=0Tf \cdot Sg=0, for fA(X)f\in A(X) and gA(X,E)g\in A(X,E). If TT and SS are jointly separating bijections between Banach algebras of scalar-valued functions of this class, then they induce a homeomorphism between XX and YY and, furthermore, T1T^{-1} and S1S^{-1} are also jointly separating maps.

Keywords

Cite

@article{arxiv.1804.10915,
  title  = {Jointly separating maps between vector-valued function spaces},
  author = {Z. Pourghobadi and M. Najafi Tavani and F. Sady},
  journal= {arXiv preprint arXiv:1804.10915},
  year   = {2018}
}