Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Computing quantum correlation functions by Importance Sampling method
  based on path integrals   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.

33
The categories of this paper are: plasm-ph
35
The categories of this paper are: mtrl-th
4
The categories of this paper are: cond-mat
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph
14
The categories of this paper are: math-ph
6
The categories of this paper are: astro-ph
22
The categories of this paper are: chao-dyn
9
The categories of this paper are: nlin
32
The categories of this paper are: atom-ph
18
The categories of this paper are: econ
1
The categories of this paper are: cs
15
The categories of this paper are: nucl-ex
5
The categories of this paper are: gr-qc
36
The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int