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arXiv · 2510.06398

Quasi-greedy Markushevich bases, duality and norming subspaces

Miguel Berasategui
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Abstract

We prove that if $\mathcal{X}$ is a quasi-greedy Markushevich basis of a Banach space $\mathbb{X}$, its dual basis $\mathcal{X}^*$ spans a norming subspace of $\mathbb{X}^*$. We also prove this result for weaker forms of quasi-greediness, and study the cases of other greedy-like properties from the literature.

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Miguel Berasategui. 2025-10-07. Quasi-greedy Markushevich bases, duality and norming subspaces. https://arxiv.org/abs/2510.06398

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