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Diffusion Monte Carlo

V. Apaja

Published Aug 1, 2025• 0 citations

Abstract

A wave function written in analytical form is a simplistic version of the true wave function. Normally, a wave function evolves in time in an oscillatory fashion, each oscillation corresponds to an energy eigenvalue—quantities we can't compute in a many-body system. In imaginary time, however, the oscillations turn into decaying amplitudes, the higher the energy the faster it decays. This gives us the change to project out a low-energy state. The algorithm that does imaginary-time evolution is called diffusion Monte Carlo. It won't lead to a better analytical form of a wave function, but nevertheless lets us compute its properties, which, after all, is all we want.

DOI: 10.1088/978-0-7503-6310-5ch4

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