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arXiv · 1705.03936

Optimality of the rearrangement inequality with applications to Lorentz-type sequence spaces

Fernando Albiac·Jose L. Ansorena·Denny Leung·Ben Wallis
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Abstract

We characterize the sequences $(w_i)_{i=1}^\infty$ of non-negative numbers for which \[ \sum_{i=1}^\infty a_i w_i \quad \text{ is of the same order as } \quad \sup_n \sum_{i=1}^n a_i w_{1+n-i} \] when $(a_i)_{i=1}^\infty$ runs over all non-increasing sequences of non-negative numbers. As a by-product of our work we settle a problem raised in [F. Albiac, Jose L. Ansorena and B. Wallis; arXiv:1703.07772[math.FA]] and prove that Garling sequences spaces have no symmetric basis.

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BibTeXRIS

Fernando Albiac, Jose L. Ansorena, Denny Leung, Ben Wallis. 2017-05-10. Optimality of the rearrangement inequality with applications to Lorentz-type sequence spaces. https://arxiv.org/abs/1705.03936

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