A light weight regularization for wave function parameter gradients in quantum Monte Carlo

Abstract

The parameter derivative of the expectation value of the energy, ∂E/∂p, is a key ingredient in variational Monte Carlo (VMC) wave function optimization methods. In some cases, a naïve estimate of this derivative suffers from an infinite variance, which inhibits the efficiency of optimization methods that rely on a stable estimate of the derivative. In this work, we derive a simple regularization of the naïve estimator, which is trivial to implement in existing VMC codes, has finite variance, and a negligible bias, which can be extrapolated to zero bias with no extra cost. We use this estimator to construct an unbiased, finite variance estimation of ∂E/∂p for a multi-Slater–Jastrow trial wave function on the LiH molecule and in the optimization of a multi-Slater–Jastrow trial wave function on the CuO molecule. This regularized estimator is a simple and efficient estimator of ∂E/∂p for VMC optimization techniques.

Document Details

Document Type
Pub Defense Publication
Publication Date
Aug 01, 2020
Source ID
10.1063/5.0004008

Entities

People

  • Lucas K Wagner
  • Shivesh Pathak

Organizations

  • National Geospatial-Intelligence Agency
  • National Science Foundation
  • United States Department of Energy
  • University of Illinois Urbana–Champaign

Tags

Fields of Study

  • Mathematics

Readers

  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Solar Physics
  • Statistical inference.

Technology Areas

  • Quantum Computing