The χ-ensemble formulation of Lee and Yang is used as the basis for a theory of the degenerate Bose fluid. The expansions of the grand potential and the momentum distribution are rearranged through a set of simple transformations; the transformed expansions no longer contain free particle...

The transverse susceptibility of the c-cyclic version of the one-dimensional XY model with respect to an infinitesimal magnetic field in the x-direction is investigated in more detail. Special attention is paid to the c-cyclic version of the one-dimensional Ising model. The c-cyclic...

A hypercubic d-dimensional lattice of spins with nearest neighbor ferromagnetic coupling and next nearest neighbor antiferromagnetic coupling along a single axis is studied in the spherical model limit (n→∞) and is found to exhibit a multicritical point of the uniaxial Lifshitz type. The...

A general integral expression, valid for all intermolecular potentials, for the nondiagrammatic cluster χ'(r) obtained in the Kirkwood superposition approximation (KSA), is found by integration in bipolar coordinates of the differential expression for this cluster as given by Nijboer and Van...

In previous papers it has been shown that adding a positive scalar self-interaction (ψψ)2 to the Dirac field Lagrangian provides a reasonably satisfactory model to describe the barions. In this work, we analyze other solutions of the same nonlinear Dirac equation, making progress in the...

In a previous paper it has been shown that near every type of point μo in the field space, any GM stable C∞ unfolding Φ by appropriate diffeomorphic substitutions can be reduced to a GM standard form, i.e. an unfolding of functions, constructed from one or more simple polynomials. For μo...

The k-particle, infinite-volume distribution functions n̄k (r1, …, rk−1, γ) and modified Ursell correlation functions Ūk (r1, …, rk−1, γ) of a classical system of particles with the two-body potential q(r) + γνK(γr) are considered. The limiting values of the functions n̄k (r1,...

Experimental measurements of the diffusion coefficient of Kr in CF4atT = 243.15K in the density range 0 ϱ ⪕ 1.75ϱc are reported. The experimental data are compared with those of self-diffusion of CF4 at the same temperature. The influence of the size effect on the diffusion process is shown...

For pure fluids, the dependence of the Van der Waals parameter a on the temperature and density have been examined. The Van der Waals equation of state with an accurate hard-core part and temperature- and density-dependent parameters aij has been applied to fluid mixtures. The calculated pE and...

The Ising model with pair and triplet interactions on the triangular lattice is solved in the mean-field approximation. With a sufficiently strong triplet interaction two first-order transitions take place at low temperature, and at intermediate temperatures one transition, terminating in a...