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arXiv · 2003.04648

Query complexity and the polynomial Freiman-Ruzsa conjecture

Dmitrii Zhelezov·Dömötör Pálvölgyi
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Abstract

We prove a query complexity variant of the weak polynomial Freiman-Ruzsa conjecture in the following form. For any $\epsilon > 0$, a set $A \subset \mathbb{Z}^d$ with doubling $K$ has a subset of size at least $K^{-\frac{4}{\epsilon}}|A|$ with coordinate query complexity at most $\epsilon \log_2 |A|$. We apply this structural result to give a simple proof of the "few products, many sums" phenomenon for integer sets. The resulting bounds are explicit and improve on the seminal result of Bourgain and Chang.

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Dmitrii Zhelezov, Dömötör Pálvölgyi. 2020-03-10. Query complexity and the polynomial Freiman-Ruzsa conjecture. https://doi.org/10.1016/j.aim.2021.108043

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