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arXiv · 1311.6387

Effective Ratner theorem for ASL(2,R) and gaps in \sqrt{n} modulo 1

Tim Browning·Ilya Vinogradov
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Abstract

Let G=ASL(2,R) be the affine special linear group of the plane, and set Gamma=ASL(2,Z). Building on recent work of Str\"ombergsson we prove a rate of equidistribution for the orbits of a certain 1-dimensional unipotent flow of Gamma\G, which projects to a closed horocycle in the unit tangent bundle to the modular surface. We use this to answer a question of Elkies and McMullen by making effective the convergence of the gap distribution of \sqrt{n} modulo 1.

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Tim Browning, Ilya Vinogradov. 2013-11-25. Effective Ratner theorem for ASL(2,R) and gaps in \sqrt{n} modulo 1. https://arxiv.org/abs/1311.6387

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