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arXiv · 1402.0518

Degree reduction and graininess for Kakeya-type sets in $\mathbb{R}^3$

Larry Guth
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Abstract

Let $\frak T$ be a set of cylindrical tubes in $\mathbb{R}^3$ of length $N$ and radius 1. If the union of the tubes has volume $N^{3 - \sigma}$, and each point in the union lies in tubes pointing in three quantitatively different directions, and if a technical assumption holds, then at scale $N^\sigma$, the tubes are clustered into rectangular slabs of dimension $1 \times N^\sigma \times N^\sigma$. This estimate generalizes the graininess estimate proven by Katz-Laba-Tao. The proof is based on modeling the union of tubes with a high-degree polynomial.

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Larry Guth. 2014-02-03. Degree reduction and graininess for Kakeya-type sets in $\mathbb{R}^3$. https://arxiv.org/abs/1402.0518

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