Kasteleyn's treatment of the hamiltonian walk problem on lattice graphs is briefly reviewed. The asymptotic behaviour of the number of hamiltonian walks on the kth covering of a closed oriented lattice graph is expressed in terms of the asymptotic behaviour of the number of oriented trees on the...

The alignment average of polar molecules may be derived from their NMR spectrum, when a strong electric field is applied to the liquid. The Kerr effect can likewise be related to the alignment.

The necessary and sufficient conditions are found under which the Wigner distribution function conserves (i) positivity, and (ii) factorization. The proof is based on the study of the continuous representation of three-dimensional linear-canonical-transformed minimum-uncertainty-states. The...

The density gradient term in the free-energy expression for a fluid can, as previously shown, be corrected so that the effect of this term on the correlation length parallels the effect of the other terms. It is shown that this same correction improves the values of the critical exponents when...

The nonlinear generalization of the theory of Onsager and Machlup presented in a previous paper is extended to the case in which both of even and odd variables exist simultaneously.

The triple collision integrals in kinetic theory of gases are re-examined in terms of mass-normalized coordinate systems and new surface integrals are obtained from them. The five-dimensional surface integrals obtained are more symmetric than those known up to know and appear suggestive of...

Starting from the definition of molecular distribution functions a new hierarchy of integral equations for the equilibrium classical liquids is derived. An outline is given of why this hierarchy cannot be derived by graph theory means. In the theory, the sum of elementary diagrams is given...

Using the nonlinearized (space-dependent) Boltzmann transport equation, the effect of three-phonon normal processes on the thermal conductivity of solids has been studied. The heat energy density in a region of the system is regarded as the measure of the local temperature. This temperature is...

This article is the first in a series of four papers, which deal with the effect of hydrostatic pressure on the high resolution proton magnetic resonance spectra of methane, ethylene, methanol and ethanol. The present paper describes the spectrometer in which high resolution spectra can be...

A scheme for construction of a crossing-symmetric, unitary Regge theory of meson-meson scattering is reviewed. The construction proceeds by solution of the non-linear crossing-unitarity equations in a new formulation based entirely on partial waves. The high-energy divergences encountered in...