A streamlined proof of the Kakeya set conjecture in $\mathbb{R}^3$
Larry Guth, Hong Wang, Joshua Zahl
TL;DR
This work presents a streamlined proof of the Kakeya set conjecture in $\mathbb{R}^3$ by reducing the general problem to a sticky Kakeya framework. It develops a robust toolkit of convex-set shadings, uniform-tube decompositions, and maximal-density factoring to organize incidences, and it proves key implications between Katz–Tao and Frostman type bounds. The main results show that KT bounds imply Frostman bounds (Main Lemma 1) and, under both KT and Frostman hypotheses, yield a gain which improves KT bounds (Main Lemma 2), enabling an iterative bootstrap to the Kakeya conclusion. The approach leverages a multi-scale, incidence-geometric analysis of slabs and planks, together with a sticky/non-sticky dichotomy, to deduce large coverage by unit tubes and control multiplicities, ultimately establishing that Besicovitch sets in $\mathbb{R}^3$ have Minkowski and Hausdorff dimension $3$.
Abstract
We present a streamlined and simplified proof of the Kakeya set conjecture in $\mathbb{R}^3$.
