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DOE OSTI · 1756438

Max-independent set and the quantum alternating operator ansatz

Saleem, Zain Hamid
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Abstract

he maximum-independent set (MIS) problem of graph theory using the quantum alternating operator ansatz is studied. We perform simulations on the Rigetti Forest simulator for the square ring, K 2,3 , and K3,3 graphs and analyze the dependence of the algorithm on the depth of the circuit and initial states. The probability distribution of observation of the feasible states representing maximum-independent sets is observed to be asymmetric for the MIS problem, which is unlike the Max-Cut problem where the probability distribution of feasible states is symmetric. For asymmetric graphs, it is shown that the algorithm clearly favors the independent set with the larger number of elements even for finite circuit depth. Finally, we also compare the approximation ratios for the algorithm when we choose different initial states for the square ring graph and show that it is dependent on the choice of the initial state.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSQAOAQuantum algorithmsconstrained optimization

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Saleem, Zain Hamid. 2020-07-16. Max-independent set and the quantum alternating operator ansatz. https://doi.org/10.1142/s0219749920500112

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