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arXiv · 2606.19515

Duality for Interpolation Spaces Defined Via Slowly Varying Functions: The Case 0<q<1

P. Fernández-Martínez·M. Grover·T. M. Signes
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Abstract

Given $(A_0, A_1)$ a compatible couple of Banach spaces, we describe the dual of the limiting real interpolation space $(A_0, A_1)^{K}_{ 1,q,b}$ for $0 < q < 1$ and $b$ a slowly varying function. In the process, we use the $J$-spaces $(A_0, A_1)^{J}_{ 1,q,b}$ and we establish an equivalence theorem for $K$ and $J$ spaces of independent interest. We also give examples that recover known results on this topic.

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P. Fernández-Martínez, M. Grover, T. M. Signes. 2026-06-17. Duality for Interpolation Spaces Defined Via Slowly Varying Functions: The Case 0<q<1. https://arxiv.org/abs/2606.19515

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