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arXiv 1302.6019math.FA
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关于局部凸向量空间的可凹性

On dentability in locally convex vector spaces

Oleg Reinov, Asfand Fahad

摘要:

对于局部凸向量空间(l.c.v.s.)$E$和为零的绝对凸邻域$V$,$E$的有界子集$A$被称为$V$ -可dentable(分别地,$V$ -f-dentable),如果对于任何$ε>0$存在$x\in A$,使得$$x\notin \bar{co} (A\setminus (x+εV)) $$(分别地,使得$$ x\notin {co} (A\setminus (x+εV))). $$)这里,“$\bar{co}$“表示集合的凸包的$E$中的闭包。本文给出了一个定理,证明了对于局部凸向量空间的一类有界子集$B$,以下定理成立:$(V)$ $B$的每个子集是$V$ -可齿的当且仅当$B$的每个子集是$V$ -可齿的.证明是纯粹的几何和独立的任何相关的事实。作为结果(在$B$是l.c.v.s.的完全凸有界可度量子集的特定情况下),我们获得了EliasSaab的1978年假设的正解(参见“On the Radon-Nikodym property in a class of局部凸spaces“,PacificJ.Math.75,No.1,1978,281-291中的第290页)。

英文摘要:

For a locally convex vector space (l.c.v.s.) $E$ and an absolutely convex neighborhood $V$ of zero, a bounded subset $A$ of $E$ is said to be $V$-dentable (respectively, $V$-f-dentable) if for any $ε>0$ there exists an $x\in A$ so that $$x\notin \bar{co} (A\setminus (x+εV)) $$ (respectively, so that $$ x\notin {co} (A\setminus (x+εV))). $$ Here, "$\bar{co}$" denotes the closure in $E$ of the convex hull of a set. We present a theorem which says that for a wide class of bounded subsets $B$ of locally convex vector spaces the following is true: $(V)$ every subset of $B$ is $V$-dentable if and only if every subset of $B$ is $V$-f-dentable. The proof is purely geometrical and independent of any related facts. As a consequence (in the particular case where $B$ is complete convex bounded metrizable subset of a l.c.v.s.), we obtain a positive solution to a 1978-hypothesis of Elias Saab (see p. 290 in "On the Radon-Nikodym property in a class of locally convex spaces", Pacific J. Math. 75, No. 1, 1978, 281-291).

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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