Self-maps under the compact-open topology

TL;DR

This paper studies the space of continuous self-maps on the Stone-ch remainder of the integers, revealing its topological properties, the density of certain maps, and the independence of the existence of P-points from ZFC.

Contribution

It establishes new topological properties of the space of self-maps on ch remainders, including Baire property, density of extensions, and independence results.

Findings

$C_k(\u00a5^*,a5^*)$ is a Baire space

Extensions of injective maps are dense and form weak P-points

Existence of P-points in $C_k(\u00a5^*,a5^*)$ is independent of ZFC

Abstract

This paper investigates the space $C_k(\omega^*,\omega^*)$, the space of continuous self-maps on the Stone-\v{C}ech remainder of the integers, $\omega^*$, equipped with the compact-open topology. Our main results are that (1) $C_k(\omega^*,\omega^*)$ is Baire, (2) Stone-\v{C}ech extensions of injective maps on $\omega$ form a dense set of weak $P$-points in $C_k(\omega^*,\omega^*)$, (3) it is independent of ZFC whether $C_k(\omega^*,\omega^*)$ contains $P$-points, and that (4) $C_k(\omega^*,\omega^*)$ is not an $F$-space, but contains, as $\omega^*$, no non-trivial convergent sequences.