Journal of Physical Studies 11(2), 133–141 (2007)
DOI: https://doi.org/10.30970/jps.11.133

STATISTICAL FIELD THEORY FOR A MULTICOMPONENT FLUID: THE COLLECTIVE VARIABLES APPROACH

O. Patsahan^{1}, I. Mryglod^{1}, J.-M. Caillol^{2}
^{1}Institute for Condensed Matter Physics, National Academy of Sciences of Ukraine,
1 Svientsitskii St., Lviv, UA–79011, Ukraine
^{2}Laboratoire de Physique Théorique CNRS UMR 8627,
B\^at. 210 Université de Paris-Sud 91405 Orsay Cedex, France

Using the collective variables (CV) method the basic relations of statistical field theory of a multicomponent non-homogeneous fluids are reconsidered. The corresponding CV action depends on two sets of scalar fields: the fields $ρ_{α}$ connected to the local density fluctuations of the $α$th species of particles and those $ω_{α}$ conjugated to $ρ_{α}$. Explicit expressions for the CV field correlations and their relation to the density correlation functions are found. The perturbation theory is formulated and a mean field level (MF) of this theory is considered in detail.

PACS number(s): 05.70.Fh, 02.70.Rr