par Hohenberg, Pierre;De Leener, Michel ;Resibois, Pierre
Référence Physica, 65, 3, page (505-521)
Publication Publié, 1973-05
Article révisé par les pairs
Résumé : The time-dependent spin-correlation function is investigated near Tc in d dimensions, by a microscopic kinetic theory in a model with long-range forces. For the isotropic ferromagnet it is shown that there exists at least a large precritical region where, in the absence of a magnetic field and for T > Tc, dynamic scaling holds up to d = 6. In the range 4 < d < 6, however, the characteristics frequency does not scale from above to below Tc, since there are two distinct scaling lengths below Tc. For d > 6 the results agree with the conventional (Van Hove) theory. Conjectures are made about the true critical behavior, and a detailed comparison is presented between the kinetic theory and the phenomenological theory of dynamic scaling. For the anti-ferromagnet the conventional theory is recovered for d ≥ -4. © 1973.