English

An exceptional set estimate for restricted projections to lines in $\mathbb{R}^3$

Classical Analysis and ODEs 2022-10-05 v2

Abstract

Let γ:[0,1]S2\gamma:[0,1]\rightarrow \mathbb{S}^{2} be a non-degenerate curve in R3\mathbb{R}^3, that is to say, det(γ(θ),γ(θ),γ(θ))0\det\big(\gamma(\theta),\gamma'(\theta),\gamma''(\theta)\big)\neq 0. For each θ[0,1]\theta\in[0,1], let lθ={tγ(θ):tR}l_\theta=\{t\gamma(\theta):t\in\mathbb{R}\} and ρθ:R3lθ\rho_\theta:\mathbb{R}^3\rightarrow l_\theta be the orthogonal projections. We prove an exceptional set estimate. For any Borel set AR3A\subset\mathbb{R}^3 and 0s10\le s\le 1, define Es(A):={θ[0,1]:dim(ρθ(A))<s}E_s(A):=\{\theta\in[0,1]: \text{dim}(\rho_\theta(A))<s\}. We have dim(Es(A))1+sdim(A)2\text{dim}(E_s(A))\le 1+\frac{s-\text{dim}(A)}{2}.

Keywords

Cite

@article{arxiv.2209.15152,
  title  = {An exceptional set estimate for restricted projections to lines in $\mathbb{R}^3$},
  author = {Shengwen Gan and Larry Guth and Dominique Maldague},
  journal= {arXiv preprint arXiv:2209.15152},
  year   = {2022}
}

Comments

11 pages. arXiv admin note: substantial text overlap with arXiv:2207.13844