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arXiv · 2005.09395

Tychonoff spaces and a ring theoretic order on $\text{C}(X)$

Abstract

The reduced ring order (rr-order) is a natural partial order on a reduced ring $R$ given by $r\le_{\text{rr}} s$ if $r^2=rs$. It can be studied algebraically or topologically in rings of the form $\text{C}(X)$. The focus here is on those reduced rings in which each pair of elements has an infimum in the rr-order, and what this implies for $X$. A space $X$ is called rr-good if $\text{C}(X)$ has this property. Surprisingly both locally connected and basically disconnected spaces share this property. The rr-good property is studied under various topological conditions including its behaviour under Cartesian products. The product of two rr-good spaces can fail to be rr-good (e.g., $\beta \mathbf{R}\times \beta \mathbf{R}$), however, the product of a $P$-space and an rr-good weakly Lindel\"of space is always rr-good. $P$-spaces, $F$-spaces and $U$-spaces play a role, as do Glicksberg's theorem and work by Comfort, Hindman and Negrepontis.

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BibTeXRIS

W. D. Burgess, R. Raphael. 2020-05-19. Tychonoff spaces and a ring theoretic order on $\text{C}(X)$. https://arxiv.org/abs/2005.09395

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