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arXiv · 1309.4262

Product set phenomena for countable groups

MIchael Björklund·Alexander Fish
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Abstract

We develop in this paper general techniques to analyze local combinatorial structures in product sets of two subsets of a countable group which are "large" with respect to certain classes of (not necessarily invariant) means on the group. As applications of our methods, we extend and quantify a series of recent results by Jin, Bergelson-Furstenberg-Weiss, Beiglb\"ock-Bergelson-Fish, Griesmer and DiNasso-Lupini to general countable groups.

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MIchael Björklund, Alexander Fish. 2013-09-17. Product set phenomena for countable groups. https://arxiv.org/abs/1309.4262

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