An extended lattice model of liquid helium four
Abstract
The low and high temperature behavior of liquid 4He is described in terms of an extended lattice model. Paying particular attention to the kinematical interaction and to the hard core of the bosons leads to a unified theory for the low temperature behavior and for the lambda transition. Since the hard core boson operators in the lattice model correspond to spin one half operators, the hamiltonian is interpreted as the hamiltonian of a magnetic system of oblate form. The equations of motion of the creation and annihilation operators are decoupled with the aid of a momentum dependent Bogoliubovlike transformation.
 Publication:

Final Report National Bureau of Standards
 Pub Date:
 February 1975
 Bibcode:
 1975nbs..reptU....M
 Keywords:

 Bosons;
 Helium Isotopes;
 Lattices (Mathematics);
 Liquid Helium;
 Bogoliubov Theory;
 Hamiltonian Functions;
 Kinematic Equations;
 Lamb Waves;
 Engineering (General)