Gelfand numbers and widths
نویسندگان
چکیده
منابع مشابه
Gelfand numbers and widths
In general, the Gelfand widths cn(T ) of a map T between Banach spaces X and Y are not equivalent to the Gelfand numbers cn(T ) of T . We show that cn(T ) = cn(T ) (n ∈ N) provided that X and Y are uniformly convex and uniformly smooth, and T has trivial kernel and dense range. c ⃝ 2012 Elsevier Inc. All rights reserved.
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ژورنال
عنوان ژورنال: Journal of Approximation Theory
سال: 2013
ISSN: 0021-9045
DOI: 10.1016/j.jat.2012.10.008