Annotation
The theory of perturbations is investigated for statistical systems in the absence of the small interaction parameter. A new form is suggested for matching conditions defining the parameters of the sample Greenian in iterating nonlinear propagator equations. Superharmonic, semiharmonic, and pseudoharmonic approximations for a molecular crystal are considered as examples.
© 2016 Publisher M.V.Lomonosov Moscow State University
Authors
V.I. Yukalov
Department of Theoretical Physics
Department of Theoretical Physics
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