The Diffusion Equation on a Hypersphere

We study the diffusion equation on the surface of a 4D sphere and obtain a Kubo formula for the diffusion coefficient

Sine-Gordon theory for the equation of state of classical hard-core Coulomb systems. II. High-temperature expansion

We perform a high-temperature expansion of the grand potential of the restrictive primitive model of electrolytes in the frame of the extended sine-Gordon theory exposed in the companion paper. We recover a result already obtained by Stell an Lebowitz (J. Chem. Phys., 49, 3706 (1968)) by means of diagrammatic expansions

Liquid-Vapor Transition and Critical Behavior of The Ultrasoft Restricted Primitive Model of Polyelectrolytes : a Monte Carlo Study

We present a Monte-Carlo study of the liquid-vapor transition and the critical behavior of a model of polyelectrolytes with soft gaussian charge distributions introduced recently by Coslovich, Hansen, and Kahl [J. Chem. Phys. \textbf{134}, 244514 (2011)]. A finite size study involving four different volumes in the grand canonical ensemble yields a precise determination of the critical temperature, chemical potential, and density of the model. Attempts to determine the nature of the criticality and to obtain reliable values for the critical exponents are not conclusive.Comment: 14 pages, 4 figure

Exact Renormalization Group : A New Method for Blocking the Action

We consider the exact renormalization group for a non-canonical scalar field theory in which the field is coupled to the external source in a special non linear way. The Wilsonian action and the average effective action are then simply related by a Legendre transformation up to a trivial quadratic form. An exact mapping between canonical and non-canonical theories is obtained as well as the relations between their flows. An application to the theory of liquids is sketched

Monte Carlo simulations of the screening potential of the Yukawa one-component plasma

A Monte Carlo scheme to sample the screening potential H(r) of Yukawa plasmas notably at short distances is presented. This scheme is based on an importance sampling technique. Comparisons with former results for the Coulombic one-component plasma are given. Our Monte Carlo simulations yield an accurate estimate of H(r) as well for short range and long range interparticle distances.Comment: to be published in Journal of Physics A: Mathematical and Genera

Statistical field theory for simple fluids: the collective variables representation

An alternative representation of an exact statistical field theory for simple fluids, based on the method of collective variables, is presented. The results obtained are examined from the point of another version of theory that was developed recently by performing a Hubbard-Stratonovich transformation of the configurational Boltzmann factor [J.-M. Caillol, Mol. Phys. 101 (2003) 1617]. The analytical expressions for the pressure and the free energy are derived in two-loop approximation for both versions of theory and it is shown that they are indeed equivalent.The results yield a new type approximation within an untested approximation scheme

Transport Coefficients of the Yukawa One Component Plasma

We present equilibrium molecular-dynamics computations of the thermal conductivity and the two viscosities of the Yukawa one-component plasma. The simulations were performed within periodic boundary conditions and Ewald sums were implemented for the potentials, the forces, and for all the currents which enter the Kubo formulas. For large values of the screening parameter, our estimates of the shear viscosity and the thermal conductivity are in good agreement with the predictions of the Chapman-Enskog theory.Comment: 11 pages, 2 figure