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arXiv · 2005.13089

Quantum Algorithm for Approximating Maximum Independent Sets

Hongye Yu·Frank Wilczek·Biao Wu
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Abstract

We present a quantum algorithm for approximating maximum independent sets of a graph based on quantum non-Abelian adiabatic mixing in the sub-Hilbert space of degenerate ground states, which generates quantum annealing in a secondary Hamiltonian. For both sparse and dense graphs, our quantum algorithm on average can find an independent set of size very close to $\alpha(G)$, which is the size of the maximum independent set of a given graph $G$. Numerical results indicate that an $O(n^2)$ time complexity quantum algorithm is sufficient for finding an independent set of size $(1-\epsilon)\alpha(G)$. The best classical approximation algorithm can produce in polynomial time an independent set of size about half of $\alpha(G)$.

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Hongye Yu, Frank Wilczek, Biao Wu. 2020-05-26. Quantum Algorithm for Approximating Maximum Independent Sets. https://doi.org/10.1088/0256-307x/38/3/030304

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