On the Erd\H{o}s distance problem

Theophilus Agama

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arXiv · 2002.00502

On the Erd\H{o}s distance problem

Theophilus Agama

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Abstract

In this paper, using the compression method, we recover the lower bound for the Erd\H{o}s unit distance problem and provide an alternative proof to the distinct distance conjecture. In particular, in $\mathbb{R}^k$ for all $k\geq 2$, we have \begin{align} \#\bigg\{(\vec{x}_t,\vec{x_j})\in \mathbb{E}\subset\mathbb{R}^k~:~||\vec{x_j}-\vec{x_t}||=1,~1\leq t,j\leq n\bigg\}\geq C\frac{\sqrt{k}}{2}n^{1+o(1)}\nonumber \end{align} for some $C>0$. We also show that \begin{align} \# \bigg\{d_j:d_j=||\vec{x_s}-\vec{y_t}||,~d_j\neq d_i,~1\leq s,t\leq n\bigg\}\geq D\frac{\sqrt{k}}{2}n^{\frac{2}{k}-o(1)}\nonumber \end{align} for some $D>0$. These lower bounds generalize the lower bounds of the Erd\H{o}s unit distance and the distinct distance problem to higher dimensions.

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Theophilus Agama. 2020-02-02. On the Erd\H{o}s distance problem. https://arxiv.org/abs/2002.00502

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