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arXiv · 2110.06291

The Butterfly lemma

Jesús M. F. Castillo·Daniel Morales
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Abstract

The Butterfly lemma we present can be considered a reiteration theorem for differentials generated from a complex interpolation process for families of K\"othe spaces. The lemma will be used to clarify the effect of different configurations in the resulting differential (because although interpolation is an orientation-free process, the obtention of differentials is not) and to round off a few aspects of Kalton's interpolation theorem.

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Jesús M. F. Castillo, Daniel Morales. 2021-10-12. The Butterfly lemma. https://arxiv.org/abs/2110.06291

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