Ordered Compactifications and Families of Maps
نویسنده
چکیده
For a T3.s-ordered space, certain families of maps are designated as "defining families." For each such defining family we construct the smallest T=-ordered compactification such that each member of the family can be extended to the compactification space. Each defining family also generates a quasi-uniformity on the space whose bicompletion produces the same T=-ordered
منابع مشابه
Ordered Quotients and the Semilattice of Ordered Compactifications
Douglas D. MOONEY, Thomas A. RICHMOND Western Kentucky University Bowling Green, KY 42101 USA The ideas of quotient maps, quotient spaces, and upper semicontinuous decompositions are extended to the setting of ordered topological spaces. These tools are used to investigate the semilattice of ordered compactifications and to construct ordered compactifications with o-totally disconnected and o-z...
متن کاملPosets of Ordered Compactifications
If (X ′, τ ′,≤′) is an ordered compactification of the partially ordered topological space (X, τ,≤) such that ≤′ is the smallest order that renders (X ′, τ ′,≤′) a T2-ordered compactification of X, then X ′ is called a Nachbin(or order-strict) compactification of (X, τ,≤). If (X ′, τ ′,≤∗) is a finite-point ordered compactification of (X, τ,≤), the Nachbin order ≤′ for (X ′, τ ′) is described i...
متن کاملOrdered Compactifications of Products of Two Totally Ordered Spaces
We describe the semilattice of ordered compactifications ofX×Y smaller than βoX×βoY whereX and Y are certain totally ordered topological spaces, and where βoZ denotes the Stone–Čech orderedor Nachbin-compactification of Z. These basic cases are used to illustrate techniques for describing the semilattice of ordered compactifications ofX×Y smaller than βoX×βoY for arbitrary totally ordered topol...
متن کاملCardinality and Structure of Semilattices of Ordered Compactifications
Cardinalities and lattice structures which are attainable by semilattices of ordered compactifications of completely regular ordered spaces are examined. Visliseni and Flachsmeyer have shown that every infinite cardinal is attainable as the cardinality of a semilattice of compactifications of a Tychonoff space. Among the finite cardinals, however, only the Bell numbers are attainable as cardina...
متن کاملOrdered Compactifications with Countable Remainders
Countable compactifications of topological spaces have been studied in [1], [5], [7], and [9]. In [7], Magill showed that a locally compact, T2 topological space X has a countable T2 compactification if and only if it has n-point T2 compactifications for every integer n ≥ 1. We generalize this theorem to T2-ordered compactifications of ordered topological spaces. Before starting our generalizat...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2004