Statistical mechanics and the physics of many-particle model systems

Journal Article · Tue Dec 15 04:00:00 EST 2009 · Physics of Particles and Nuclei

DOI:https://doi.org/10.1134/S1063779609070016· OSTI ID:22974944

The development of methods of quantum statistical mechanics is considered in light of their applications to quantum solid-state theory. We discuss fundamental problems of the physics of magnetic materials and the methods of the quantum theory of magnetism, including the method of two-time temperature Green’s functions, which is widely used in various physical problems of many-particle systems with interaction. Quantum cooperative effects and quasi-particle dynamics in the basic microscopic models of quantum theory of magnetism: the Heisenberg model, the Hubbard model, the Anderson Model, and the spinfermion model are considered in the framework of novel self-consistent-field approximation. We present a comparative analysis of these models; in particular, we compare their applicability for description of complex magnetic materials. The concepts of broken symmetry, quantum protectorate, and quasi-averages are analyzed in the context of quantum theory of magnetism and theory of superconductivity. The notion of broken symmetry is presented within the nonequilibrium statistical operator approach developed by D.N. Zubarev. In the framework of the latter approach we discuss the derivation of kinetic equations for a system in a thermal bath. Finally, the results of investigation of the dynamic behavior of a particle in an environment, taking into account dissipative effects, are presented.

• OSTI ID: 22974944
• Journal Information: Physics of Particles and Nuclei, Journal Name: Physics of Particles and Nuclei Journal Issue: 7 Vol. 40; ISSN 1063-7796
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
HEISENBERG MODEL
HUBBARD MODEL
MAGNETIC MATERIALS
MAGNETISM
MAGNETIZATION
QUANTUM MECHANICS
QUASI PARTICLES
SELF-CONSISTENT FIELD
STATISTICAL MECHANICS
SYMMETRY BREAKING