By a *-compactification of a
T0
quasi-uniform space (
X, U
) we mean a compact
T0
quasi-uniform space (
Y, V
) that has a
T
(
V
∨
V−1
)-dense subspace quasi-isomorphic to (
X, U
). We prove that (
X, U
) has a *-compactification if and only if its
T0
biocompletion \documentclass{aastex}
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\begin{document}
$$({\tilde X},\tilde {\mathcal{U}})$$
\end{document} is compact. We also show that, in this case, \documentclass{aastex}
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\begin{document}
$$({\tilde X},\tilde {\mathcal{U}})$$
\end{document} is the maximal *-compactification of (
X, U
) and (
X
∪
G
(
X
), \documentclass{aastex}
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\usepackage{textcomp}
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\usepackage{portland,xspace}
\usepackage{amsmath,amsxtra}
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\DeclareMathSizes{10}{9}{7}{6}
\begin{document}
$$\tilde {\mathcal{U}}$$
\end{document}|
X
∪
G
(
X
)
) is its minimal *-compactification, where
G
(
X
) is the set of all points of \documentclass{aastex}
\usepackage{amsbsy}
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\begin{document}
$$\tilde X$$
\end{document} which are
T
(\documentclass{aastex}
\usepackage{amsbsy}
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\usepackage{pifont}
\usepackage{stmaryrd}
\usepackage{textcomp}
\usepackage{upgreek}
\usepackage{portland,xspace}
\usepackage{amsmath,amsxtra}
\usepackage{bbm}
\pagestyle{empty}
\DeclareMathSizes{10}{9}{7}{6}
\begin{document}
$$\tilde {\mathcal{U}}$$
\end{document})-closed (we remark that as partial order of *-compactifications we use the inverse of the partial order used for
T2
compactifications of Tychonoff spaces). Applications of our results to some examples in theoretical computer science are given.