Quantitative Carleson's conjecture for Ahlfors regular domains
Emily Casey, Xavier Tolsa, Michele Villa
TL;DR
This work proves a quantitative version of Carleson's epsilon^2 conjecture in arbitrary dimensions by introducing the geometric coefficients $a$ and ${\varepsilon}_n$ that capture boundary flatness through eigenvalue data and spherical domains. The authors establish an equivalence: ADR boundaries with two-sided corkscrew structure are UR if and only if a Carleson-type integral bound holds for either $a$ or ${\varepsilon}_n$, connecting geometric regularity to harmonic-analytic control. A central strategy is a corona decomposition into Lipschitz (CAD) subdomains, allowing transfer of CAD estimates and the Alt–Caffarelli–Friedman framework to the full domains. The approach also provides a direct bound of ${\varepsilon}_n$ in terms of centered $\beta$-numbers, linking the new coefficients to the classical strong geometric lemma. Overall, the results advance the understanding of higher-codimensional uniform rectifiability and harmonic measure through quantitative geometric coefficients and multiscale decompositions.
Abstract
In this article, we prove a quantitative version of Carleson's $\varepsilon^2$ conjecture in higher dimension: we characterise those Ahlfors-David regular domains in $\mathbb{R}^{n+1}$ for which the Carleson's coefficients satisfy the so-called strong geometric lemma.
