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arXiv · 2209.10456

Good functions, measures, and the Kleinbock-Tomanov conjecture

Victor Beresnevich·Shreyasi Datta·Anish Ghosh
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Abstract

In this paper we prove a conjecture of Kleinbock and Tomanov \cite[Conjecture~FP]{KT} on Diophantine properties of a large class of fractal measures on $\mathbb{Q}_p^n$. More generally, we establish the $p$-adic analogues of the influential results of Kleinbock, Lindenstrauss, and Weiss \cite{KLW} on Diophantine properties of friendly measures. We further prove the $p$-adic analogue of one of the main results in \cite{Kleinbock-exponent} due to Kleinbock concerning Diophantine inheritance of affine subspaces, which answers a question of Kleinbock. One of the key ingredients in the proofs of \cite{KLW} is a result on $(C, \alpha)$-good functions whose proof crucially uses the mean value theorem. Our main technical innovation is an alternative approach to establishing that certain functions are $(C, \alpha)$-good in the $p$-adic setting. We believe this result will be of independent interest.

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Victor Beresnevich, Shreyasi Datta, Anish Ghosh. 2022-09-21. Good functions, measures, and the Kleinbock-Tomanov conjecture. https://doi.org/10.1515/crelle-2024-0052

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