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arXiv · 2507.09962

Lacunary $δ$-Discretised Spherical Maximal Operators

Surjeet Singh Choudhary·Ji Li·Chong-Wei Liang·Chun-Yen Shen
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Abstract

We study the lacunary analogue of the $δ$-discretised spherical maximal operators introduced by Hickman and Jančar, for $δ\in (0, 1/2)$, and establish the boundedness on $L^p$ for all $1 < p < \infty$, along with the endpoint weak-type estimate $H^1 \to L^{1,\infty}$. We also prove the corresponding $L^p$ boundedness for the multi-parameter variant. The constants in these bounds are uniform in $δ$, and thus, by taking the limit $δ\to 0^+$, our results recover the classical boundedness of the lacunary spherical maximal function.

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Surjeet Singh Choudhary, Ji Li, Chong-Wei Liang, Chun-Yen Shen. 2026-09-13. Lacunary $δ$-Discretised Spherical Maximal Operators. https://arxiv.org/abs/2507.09962

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