VALIDITY OF MANY-BODY APPROXIMATION METHODS FOR A SOLVABLE MODEL II: LINEARIZATION PROCEDURES.

Abstract

The validity of methods used in the study of many particle systems was investigated by using the same approximations in treating a simple model for which exact solutions are avail able. The model consisted of N fermions distributed in two Nfold degenerate levels and interacting via a monopole-monopole force. The excitation of the first collective state above the ground state was calculated using the folowing methods: (1) The method of linearized equations of motion, (2) linearization with the inclusion of renormalized single particle energies, (3) a new self-consistent linearization method. The results of these approximation methods were then compared with exact results and with the results of ordinary perturbation theory found in a previous paper. It was found that renormalization of the single particle energies leads to a considerable improvement of the results over that obtained with ordinary linearization method, especially for small numbers of particles. Further improvement was obtained with the self-consistent linearization method. The possibility of applying this latter method to more realistic problems was briefly discussed. (Author)

Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1963
Accession Number
AD0601035

Entities

People

  • A. J. Glick
  • H. J. Lipkin
  • N. Meshkov

Organizations

  • University of Maryland

Tags

DTIC Thesaurus Topics

  • Equations
  • Equations Of Motion
  • Excitation
  • Ground State
  • Inclusions
  • Mathematics
  • Particles
  • Perturbation Theory
  • Perturbations

Fields of Study

  • Physics

Readers

  • Computational Modeling and Simulation
  • Fluid Dynamics.
  • Quantum spin resonance or Electron Paramagnetic Resonance spectroscopy.