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arXiv · 2606.18136

The sharp extension norm for a planar sector

Rupert L. Frank·Paata Ivanisvili
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Abstract

We compute explicitly the infimum of the norms of $W^{1,2}$-extension operators for planar sectors and exhibit an extension operator attaining this infimum. This solves an open problem posed by Maz'ya.

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Rupert L. Frank, Paata Ivanisvili. 2026-06-16. The sharp extension norm for a planar sector. https://arxiv.org/abs/2606.18136

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