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تسجيل مستخدم جديدA note on weak-star and norm Borel sets in the dual of the space of continuous functions
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تأليف
S. Ferrari
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Let $Bo(T,tau)$ be the Borel $sigma$-algebra generated by the topology $tau$ on $T$. In this paper we show that if $K$ is a Hausdorff compact space, then every subset of $K$ is a Borel set if, and only if, $$Bo(C^*(K),w^*)=Bo(C^*(K),|cdot|);$$ where $w^*$ denotes the weak-star topology and $|cdot|$ is the dual norm with respect to the sup-norm on the space of real-valued continuous functions $C(K)$. Furthermore we study the topological properties of the Hausdorff compact spaces $K$ such that every subset is a Borel set. In particular we show that, if the axiom of choice holds true, then $K$ is scattered.
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