3-BODY PROBLEM IN THE ONE-DIMENSIONAL HUBBARD-MODEL

Electron correlation is studied in the special case of a single reversed spin in an otherwise fully aligned band in the one-dimensional Hubbard model for the purpose of examining the author's previous theory which exactly takes account of the three-body correlation. The importance of the three-body correlation is demonstrated through a comparison of the author's results with those of exact theories. The ground-state energy and the single particle spectra are in good agreement with McGuire-Lieb-Wu's exact solution and also with exact numerical solutions for finite size systems over a wide range of the intraatomic Coulomb integral and the electron number.