Supercritical fluid of particles with a Yukawa potential: A new approximation for the direct correlation function and the Widom line

We propose an approximation of a direct correlation function corresponding to the linearization with respect to ?β?(r) of a generalized mean spherical approximation for a hard-core multi-Yukawa system of particles. We use the results to study the behavior of maximums of thermodynamic response functions in the supercritical region of a fluid with a two-term Yukawa potential imitating the Lennard-Jones potential.     

Ultrametricity of the state space in glasses

We review the results related to the ultrametricity notion in glasses. We present the proof of the ultrametricity of the replica space for an arbitrary spin glass model with reflection symmetry. We solve the problem of describing the dynamics of a system with an ultrametric state space using the Keldysh functional method for nonequilibrium dynamics in which the quasinonergodicity of the system is taken into account by introducing a hierarchical spectrum of relaxation times.     

Orientation ordering and the transition to the orientational glass state in fullerite C<Subscript>60</Subscript>

We propose a model for describing the low-temperature transition to the orientational glass state in solid molecular C₆₀ in the framework of a theory similar to spin glass theory. We find a replica symmetric solution and also break the replica symmetry. The obtained results agree with experimental data on the partial retention of the orientational long-range order in the glass phase and on the presence of a broad maximum on the curve corresponding to the temperature dependence of the orientational part of the heat capacity. __________ Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 155, No. 2, pp. 356–368, May, 2008.     

Bose condensate of ultracold atoms in traps: Bose-bose and bose-fermi mixtures

We review our papers devoted to theoretical studies of the behavior of mixtures of ultracold atoms in optomagnetic traps. We discuss the phase separation and vortexlike states in mixtures of bosonic atoms and also the stability and vortexlike states in Bose-Fermi mixtures with attraction between the components. __________ Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 154, No. 1, pp. 147–163, January, 2008.     

A spin-glass-like phase in complex nonmagnetic systems. Various kinds of replica symmetry breaking

A brief review of the works of the authors on generalized spin glass models is given. The problem of the dependence of transition scenario on different factors is discussed. A classification of spin glasses behavior as depending on symmetry characteristics of systems is proposed.