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arXiv · 2507.04405

Twisted Diophantine approximation on manifolds

Victor Beresnevich·David Simmons·Sanju Velani
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Abstract

In twisted Diophantine approximation, for a fixed $m\times n$ matrix $\boldsymbol\alpha$ one is interested in sets of vectors $\boldsymbol\beta\in\mathbb R^m$ such that the system of affine forms $\mathbb R^n \ni \mathbf q \mapsto \boldsymbol\alpha\mathbf q + \boldsymbol\beta \in \mathbb R^m$ satisfies some given Diophantine condition. In this paper we introduce the notion of manifolds which are of $\boldsymbol\alpha$-twisted Khintchine type for convergence or divergence. We provide sufficient conditions under which nondegenerate analytic manifolds exhibit this twisted Khintchine-type behaviour. Furthermore, we investigate the intersection properties of the sets of $\boldsymbol\alpha$-twisted badly approximable and well approximable vectors with nondegenerate manifolds.

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Victor Beresnevich, David Simmons, Sanju Velani. 2025-07-06. Twisted Diophantine approximation on manifolds. https://arxiv.org/abs/2507.04405

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