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arXiv · 0904.1567

On uniform asymptotic upper density in locally compact abelian groups

Szilard Gy. Revesz
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Abstract

Starting out from results known for the most classical cases of N, Z^d, R^d or for sigma-finite abelian groups, here we define the notion of asymptotic uniform upper density in general locally compact abelian groups. Even if a bit surprising, the new notion proves to be the right extension of the classical cases of Z^d, R^d. The new notion is used to extend some analogous results previously obtained only for classical cases or sigma-finite abelian groups. In particular, we show the following extension of a well-known result for Z of Furstenberg: if in a general locally compact Abelian group G a subset S of G has positive uniform asymptotic upper density, then S-S is syndetic.

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Szilard Gy. Revesz. 2009-04-09. On uniform asymptotic upper density in locally compact abelian groups. https://arxiv.org/abs/0904.1567

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