Linear continuous surjections of $C_{p}$-spaces over compacta

TL;DR

This paper investigates the structure of linear continuous surjections between function spaces over compact spaces, showing that zero-dimensionality is preserved and exploring operator limitations over the pseudo-arc.

Contribution

It generalizes previous results by proving zero-dimensionality preservation under surjections for broader classes of compact spaces and examines operator restrictions over the pseudo-arc.

Findings

Zero-dimensionality is preserved under surjective linear continuous maps.

No densely defined linear continuous operator with dense image exists from the pseudo-arc space to the unit interval.

The result extends known theorems from metrizable to general compact spaces.

Abstract

Let $X$ and $Y$ be compact Hausdorff spaces and suppose that there exists a linear continuous surjection $T:C_{p}(X) \to C_{p}(Y)$, where $C_{p}(X)$ denotes the space of all real-valued continuous functions on $X$ endowed with the pointwise convergence topology. We prove that $\dim X=0$ implies $\dim Y = 0$. This generalizes a previous theorem \cite[Theorem 3.4]{LLP} for compact metrizable spaces. Also we point out that the function space $C_{p}(P)$ over the pseudo-arc $P$ admits no densely defined linear continuous operator $C_{p}(P) \to C_{p}([0,1])$ with a dense image.