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arXiv · 2310.18914

Zygmund regularity of even singular integral operators on domains

Andrei Vasin
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Abstract

Given a bounded Lipschitz domain $D\subset \mathbb{R}^d,$ a convolution Calderón-Zygmund operator $T$ and a growth function $ω(x)$ of type $n$, we study what conditions on the boundary of the domain are sufficient for boundedness of the restricted even operator $T_D$ on the generalized Zygmund space $C^ω_*(D)$. Based on a recent T(P) theorem, we prove that this holds if the smoothness of the boundary of a domain $D$ is by one point, in a sense, greater than the smoothness of the corresponding Zygmund space $C^ω_*(D)$. The main argument of the proof are the higher order gradient estimates of the transform $T_Dχ_D$ of the characteristic function of a domain with the polynomial boundary.

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Andrei Vasin. 2023-10-29. Zygmund regularity of even singular integral operators on domains. https://arxiv.org/abs/2310.18914

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