811 research outputs found
A variational perturbation scheme for many-particle systems in the functional integral approach
A variational Perturbation theory based on the functional integral approach
is formulated for many-particle systems. Using the variational action obtained
through Jensen-Peierls' inequality, a perturbative expansion scheme for the
thermodynamic potential is established. A modified Wick's theorem is obtained
for the variational perturbation expansions. This theorem allows one to carry
out systematic calculations of higher order terms without worrying about the
double counting problem. A model numerical calculation was carried out on a
nucleon gas system interacting through the Yukawa-type potential to test the
efficiency of the present method.Comment: accepted for publication in Phys. Rev.
Effects of C and Al on hydrogen embrittlement mechanism in medium Mn-Ni steels
Please click Additional Files below to see the full abstrac
- …