countable composition closedness and integer-valued continuous functions in pointfree topology

نویسندگان

bernhard banaschewski

چکیده

‎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 some topological space $x$‎.3‎. ‎for any family $(a_n)_{nin omega}$ in $a$ there exists an‎‎$l$-ring homomorphism break$varphi‎ :‎c_{bbb z}(bbb‎‎z^omega)rightarrow a$ such that $varphi(p_n)=a_n$ for the‎‎product projections break$p_n:{bbb z^omega}rightarrow bbb z$‎.‎this provides an integer-valued counterpart to a familiar result‎‎concerning real-valued continuous functions‎.

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Countable composition closedness and integer-valued continuous functions in pointfree topology

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عنوان ژورنال:
categories and general algebraic structures with applications

ناشر: shahid beheshti university

ISSN 2345-5853

دوره 1

شماره 1 2013

کلمات کلیدی
[ ' f r a m e s ' , 0 , ' d i m e n s i o n a l f r a m e s ' , ' i n t e g e r ' , ' v a l u e d c o n t i n u o u s n f u n c t i o n s o n f r a m e s ' , ' a r c h i m e d e a n $ { m a t h b b z } $ ' , ' r i n g s ' , ' c o u n t a b l e n $ m a t h b b { z } $ ' , ' c o m p o s i t i o n c l o s e d n e s s ' ]

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