Note: A pure sampling quantum Monte Carlo algorithm with independent Metropolis.
Recently, Ospadov and Rothstein published a pure sampling quantum Monte Carlo algorithm (PSQMC) that features an auxiliary Path Z that connects the midpoints of the current and proposed Paths X and Y, respectively. When sufficiently long, Path Z provides statistical independence of Paths X and Y. Under those conditions, the Metropolis decision used in PSQMC is done without any approximation, i.e. not requiring microscopic reversibility and without having to introduce any G(x x' t) factors into its decision function. This is a unique feature that contrasts with all competing reptation algorithms in the literature. An example illustrates that dependence of Paths X and Y has adverse consequences for pure sampling.
The Journal of chemical physics