Countable composition closedness and integer-valued continuous functions in pointfree topology
نویسنده
چکیده مقاله:
For any archimedean$f$-ring $A$ with unit in whichbreak$awedge (1-a)leq 0$ for all $ain A$, the following are shown to be equivalent: 1. $A$ is isomorphic to the $l$-ring ${mathfrak Z}L$ of all integer-valued continuous functions on some frame $L$. 2. $A$ is a homomorphic image of the $l$-ring $C_{Bbb Z}(X)$ of all integer-valued continuous functions, in the usual sense, on some topological space $X$. 3. For any family $(a_n)_{nin omega}$ in $A$ there exists an $l$-ring homomorphism break$varphi :C_{Bbb Z}(Bbb Z^omega)rightarrow A$ such that $varphi(p_n)=a_n$ for the product projections break$p_n:{Bbb Z^omega}rightarrow Bbb Z$. This provides an integer-valued counterpart to a familiar result concerning real-valued continuous functions.
منابع مشابه
countable composition closedness and integer-valued continuous functions in pointfree topology
for any archimedean$f$-ring $a$ with unit in whichbreak$awedge(1-a)leq 0$ for all $ain a$, the following are shown to beequivalent:1. $a$ is isomorphic to the $l$-ring ${mathfrak z}l$ of allinteger-valued continuous functions on some frame $l$. 2. $a$ is a homomorphic image of the $l$-ring $c_{bbb z}(x)$of all integer-valued continuous functions, in the usual sense,on som...
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عنوان ژورنال
دوره 1 شماره 1
صفحات 1- 10
تاریخ انتشار 2013-12-01
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