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arXiv · 2209.02799

Stochastic perturbation theory: a prequel to Reptation Quantum Monte Carlo

Stefano Baroni
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Abstract

I present a different approach to Rayleigh-Schr\"odinger perturbation theory, based on Laplace transforms and polynomial theory, yielding an iterative expression for the perturbative expansion of the energy of the non-degenerate ground state of a quantum system, which easily lends itself to symbolic computation. A stochastic interpretation of the various perturbative corrections naturally leads to a re-summation scheme that is equivalent to Reptation Quantum Monte Carlo and that actually provided the original motivation to its development in the late nineties.

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Stefano Baroni. 2022-09-06. Stochastic perturbation theory: a prequel to Reptation Quantum Monte Carlo. https://doi.org/10.1103/physreva.106.052212

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