Generating Borel sets by balls
نویسندگان
چکیده
منابع مشابه
Generating Borel Sets by Balls
It is proved that an arbitrary infinite-dimensional Banach space with basis admits an equivalent norm such that any Borel set can be obtained from balls by taking complements and countable disjoint unions. For reflexive spaces, the new norm can be chosen arbitrarily close to the initial norm.
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ژورنال
عنوان ژورنال: St. Petersburg Mathematical Journal
سال: 2006
ISSN: 1061-0022,1547-7371
DOI: 10.1090/s1061-0022-06-00925-3