# Exponential challenges in unbiasing quantum Monte Carlo algorithms with quantum computers

@inproceedings{Mazzola2022ExponentialCI, title={Exponential challenges in unbiasing quantum Monte Carlo algorithms with quantum computers}, author={Guglielmo Mazzola and Giuseppe Carleo}, year={2022} }

Recently, Huggins et. al. [1] devised a general projective Quantum Monte Carlo method suitable for implementation on quantum computers. This hybrid approach, however, relies on a subroutine –the computation of the local energy estimator on the quantum computer– that is intrinsically aﬀected by an exponential scaling of the computational time with the number of qubits. By means of numerical experiments, we show that this exponential scaling manifests prominently already on systems below the…

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