Computing quantum correlation functions by Importance Sampling method
based on path integrals
- URL: http://arxiv.org/abs/2204.12836v2
- Date: Sun, 15 May 2022 07:49:02 GMT
- Title: Computing quantum correlation functions by Importance Sampling method
based on path integrals
- Authors: Sumita Datta
- Abstract summary: An importance sampling method based on Generalized Feynman-Kac method has been used to calculate the mean values of quantum observables from quantum correlation functions.
Although the initial results are encouarging, more experimentation will be needed to improve the other existing numerical results.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: An importance sampling method based on Generalized Feynman-Kac method has
been used to calculate the mean values of quantum observables from quantum
correlation functions for many body systems both at zero and finite
temperature. Specifically, the expectation of $\langle r_i^n\rangle$, $\langle
r_{ij}^n\rangle$, $\langle r_i^{-n}\rangle$ and $\langle r_{ij}^{-n}\rangle$
for the ground state of the lithium and beryllium and the density matrix, the
partition function, the internal energy and the specific heat of a system of
quantum harmonic oscillators are computed, in good agreement with the best
nonrelativistic values for these quantities. Although the initial results are
encouarging, more experimentation will be needed to improve the other existing
numerical results beyond chemical accuracies specially for the last two
properties for lithium and beryllium. Also more work needs to be done to
improve the trial functions for finite temperature calculations.
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