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arXiv · 1508.07734

Ideals in CB(X) arising from ideals in X

M. R. Koushesh
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Abstract

Let $X$ be a completely regular topological space. We assign to each (set theoretic) ideal of $X$ an (algebraic) ideal of $C_B(X)$, the normed algebra of continuous bounded complex valued mappings on $X$ equipped with the supremum norm. We then prove several representation theorems for the assigned ideals of $C_B(X)$. This is done by associating a certain subspace of the Stone--Čech compactification $βX$ of $X$ to each ideal of $X$. This subspace of $βX$ has a simple representation, and in the case when the assigned ideal of $C_B(X)$ is closed, coincides with its spectrum as a $C^*$-subalgebra of $C_B(X)$. This in particular provides information about the spectrum of those closed ideals of $C_B(X)$ which have such representations. This includes the non-vanishing closed ideals of $C_B(X)$ whose spectrums are studied in great detail. Our representation theorems help to understand the structure of certain ideals of $C_B(X)$. This has been illustrated by means of various examples. Our approach throughout will be quite topological and makes use of the theory of the Stone--Čech compactification.

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BibTeXRIS

M. R. Koushesh. 2016-06-07. Ideals in CB(X) arising from ideals in X. https://arxiv.org/abs/1508.07734

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