On Herz's projection theorem
نویسندگان
چکیده
منابع مشابه
The Projection Theorem
Proof. (Projection Theorem) Showing that the existence of minimizer implies that V is closed is left as an exercise. So we assume that V is closed. For f ∈ H, let α := infv∈V ‖v − f‖. It is a little easier to work with this in an equivalent form, α2 = infv∈V ‖v − f‖2. Thus, for every ε > 0 there is a vε ∈ V such that α2 ≤ ‖vε − f‖2 < α2 + ε. By choosing ε = 1/n, where n is a positive integer, w...
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ژورنال
عنوان ژورنال: Illinois Journal of Mathematics
سال: 2004
ISSN: 0019-2082
DOI: 10.1215/ijm/1258138392