New NP-hardness results for 3-Coloring and 2-to-1 Label Cover

Per Austrin; Ryan O'Donnell; Li-Yang Tan; John Wright

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arXiv · 1210.5648

New NP-hardness results for 3-Coloring and 2-to-1 Label Cover

Per Austrin·Ryan O'Donnell·Li-Yang Tan·John Wright

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Abstract

We show that given a 3-colorable graph, it is NP-hard to find a 3-coloring with $(16/17 + \eps)$ of the edges bichromatic. In a related result, we show that given a satisfiable instance of the 2-to-1 Label Cover problem, it is NP-hard to find a $(23/24 + \eps)$-satisfying assignment.

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Per Austrin, Ryan O'Donnell, Li-Yang Tan, John Wright. 2012-10-20. New NP-hardness results for 3-Coloring and 2-to-1 Label Cover. https://arxiv.org/abs/1210.5648

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