Let X be a Banach space. Given M a subspace of X we denote with P M the metric projection onto M. We define ?(X ) :=sup [&P M &: M a proximinal subspace of X]. In this paper we give a bound for ?(X ). In particular, when X=L p , we obtain the inequality &P M & 2 |2Γ p&1| , for every subspace M of L
On the norms of metric projections
β Scribed by Mark A Smith
- Book ID
- 107776780
- Publisher
- Elsevier Science
- Year
- 1981
- Tongue
- English
- Weight
- 342 KB
- Volume
- 31
- Category
- Article
- ISSN
- 0021-9045
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