English

Recovering a compact Hausdorff space $X$ from the compatibility ordering on $C(X)$

Functional Analysis 2021-03-31 v2 General Topology

Abstract

Let ff and gg be scalar-valued, continuous functions on some topological space. We say that gg dominates ff in the compatibility ordering if gg coincides with ff on the support of ff. We prove that two compact Hausdorff spaces are homeomorphic if and only if there exists a compatibility isomorphism between their families of scalar-valued, continuous functions. We derive the classical theorems of Gelfand-Kolmogorov, Milgram and Kaplansky as easy corollaries to our result as well as a theorem of Jarosz [Bull. Canad. Math. Soc. 1990] thereby building~a common roof for these theorems. Sharp automatic-continuity results for compatibility isomorphisms are also established. Added on 30.03.2021: Unfortunately, Theorem 1.1 of the present manuscript is flawed. Erratum and addendum written jointly with D. H. Leung is attached. Besides providing an amendment to the said statement, it also contains more complete proof of Proposition 4.1. Theorems 1.2--1.3 are unaffected.

Keywords

Cite

@article{arxiv.1610.07842,
  title  = {Recovering a compact Hausdorff space $X$ from the compatibility ordering on $C(X)$},
  author = {Tomasz Kania and Martin Rmoutil},
  journal= {arXiv preprint arXiv:1610.07842},
  year   = {2021}
}

Comments

17 pp. + Erratum and addendum written jointly with Denny H. Leung (10 pp.) is attached