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arXiv · 2401.16518

Quantum independence and chromatic numbers

Chris Godsil·Mariia Sobchuk
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Abstract

We construct a new graph on 120 vertices whose quantum and classical independence numbers are different. At the same time, we construct an infinite family of graphs whose quantum chromatic numbers are smaller than the classical chromatic numbers. Furthermore, we discover the relation to Kochen-Specker sets that characterizes quantum cocliques that are strictly bigger than classical ones. Finally, we prove that for graphs with independence number is two, quantum and classical independence numbers coincide.

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Chris Godsil, Mariia Sobchuk. 2024-02-07. Quantum independence and chromatic numbers. https://arxiv.org/abs/2401.16518

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