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arXiv · 2301.11019

Reconstructing a point set from a random subset of its pairwise distances

António Girão·Freddie Illingworth·Lukas Michel·Emil Powierski·Alex Scott
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Abstract

Let $V$ be a set of $n$ points on the real line. Suppose that each pairwise distance is known independently with probability $p$. How much of $V$ can be reconstructed up to isometry? We prove that $p = (\log n)/n$ is a sharp threshold for reconstructing all of $V$ which improves a result of Benjamini and Tzalik. This follows from a hitting time result for the random process where the pairwise distances are revealed one-by-one uniformly at random. We also show that $1/n$ is a weak threshold for reconstructing a linear proportion of $V$.

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António Girão, Freddie Illingworth, Lukas Michel, Emil Powierski, Alex Scott. 2023-01-26. Reconstructing a point set from a random subset of its pairwise distances. https://arxiv.org/abs/2301.11019

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