Abstract and Applied Analysis

Abstract and Applied Analysis / 2006 / Article

Open Access

Volume 2006 |Article ID 042305 | https://doi.org/10.1155/AAA/2006/42305

Boris Shekhtman, Lesław Skrzypek, "Norming points and unique minimality of orthogonal projections", Abstract and Applied Analysis, vol. 2006, Article ID 042305, 17 pages, 2006. https://doi.org/10.1155/AAA/2006/42305

Norming points and unique minimality of orthogonal projections

Received05 Mar 2005
Accepted06 Apr 2005
Published22 Feb 2006

Abstract

We study the norming points and norming functionals of symmetric operators on Lp spaces for p=2m or p=2m/(2m1). We prove some general result relating uniqueness of minimal projection to the set of norming functionals. As a main application, we obtain that the Fourier projection onto span [1,sinx,cosx] is a unique minimal projection in Lp.

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Copyright © 2006 Boris Shekhtman and Lesław Skrzypek. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


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