English

Pinned distance problem, slicing measures and local smoothing estimates

Classical Analysis and ODEs 2019-07-23 v1 Combinatorics Metric Geometry

Abstract

We improve the Peres-Schlag result on pinned distances in sets of a given Hausdorff dimension. In particular, for Euclidean distances, with Δy(E)={xy:xE},\Delta^y(E) = \{|x-y|:x\in E\}, we prove that for any E,FRdE, F\subset{\Bbb R}^d, there exists a probability measure μF\mu_F on FF such that for μF\mu_F-a.e. yFy\in F, (1) dimH(Δy(E))β\dim_{{\mathcal H}}(\Delta^y(E))\geq\beta if dimH(E)+d1d+1dimH(F)>d1+β\dim_{{\mathcal H}}(E) + \frac{d-1}{d+1}\dim_{{\mathcal H}}(F) > d - 1 + \beta; (2) Δy(E)\Delta^y(E) has positive Lebesgue measure if dimH(E)+d1d+1dimH(F)>d\dim_{{\mathcal H}}(E)+\frac{d-1}{d+1}\dim_{{\mathcal H}}(F) > d; (3) Δy(E)\Delta^y(E) has non-empty interior if dimH(E)+d1d+1dimH(F)>d+1\dim_{{\mathcal H}}(E)+\frac{d-1}{d+1}\dim_{{\mathcal H}}(F) > d+1. We also show that in the case when dimH(E)+d1d+1dimH(F)>d\dim_{{\mathcal H}}(E)+\frac{d-1}{d+1}\dim_{{\mathcal H}}(F)>d, for μF\mu_F-a.e. yFy\in F, {tR:dimH({xE:xy=t})dimH(E)+d+1d1dimH(F)d} \left\{t\in{\Bbb R} : \dim_{{\mathcal H}}(\{x\in E:|x-y|=t\}) \geq \dim_{{\mathcal H}}(E)+\frac{d+1}{d-1}\dim_{{\mathcal H}}(F)-d \right\} has positive Lebesgue measure. This describes dimensions of slicing subsets of EE, sliced by spheres centered at yy. In our proof, local smoothing estimates of Fourier integral operators (FIO) plays a crucial role. In turn, we obtain results on sharpness of local smoothing estimates by constructing geometric counterexamples.

Keywords

Cite

@article{arxiv.1706.09851,
  title  = {Pinned distance problem, slicing measures and local smoothing estimates},
  author = {Alex Iosevich and Bochen Liu},
  journal= {arXiv preprint arXiv:1706.09851},
  year   = {2019}
}
R2 v1 2026-06-22T20:33:39.519Z