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arXiv · 1812.03572

Rounding semidefinite programs for large-domain problems via Brownian motion

Kevin L. Chang·Alantha Newman
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Abstract

We present a new simple method for rounding a semidefinite programming relaxation of a constraint satisfaction problem. We apply it to the problem of approximate angular synchronization. Specifically, we are given directed distances on a circle (i.e., directed angles) between pairs of elements and our goal is to assign the elements to positions on a circle so as to preserve these distances as much as possible. The feasibility of our rounding scheme is based on properties of the well-known stochastic process called Brownian motion. Based on computational and other evidence, we conjecture that this rounding scheme yields an approximation guarantee that is very close to the best-possible guarantee (assuming the Unique-Games Conjecture).

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Kevin L. Chang, Alantha Newman. 2018-12-09. Rounding semidefinite programs for large-domain problems via Brownian motion. https://arxiv.org/abs/1812.03572

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