A Generalization of Haldane state-counting procedure and π\pi-deformations of statistics

We consider the generalization of Haldane's state-counting procedure to describe all possible types of exclusion statistics which are linear in the deformation parameter $g$. The statistics are parametrized by elements of the symmetric group of the particles in question. For several specific cases we determine the form of the distribution functions which generalizes results obtained by Wu. Using them we analyze the low-temperature behavior and thermodynamic properties of these systems and compare our results with previous studies of the thermodynamics of a gas of $g$-ons. Various possible physical applications of these constructions are discussed.Comment: 17 pages, latex, 6 figures small corrections were made, reference and acknowledgments are adde

Generalization of Agranovich-Toshich transformation and constraint free bosonic representation for systems of truncated oscillators

The generalization of Agranovich-Toshich representation of paulion operators in terms of bosonic ones for the case of truncated oscillators of higher ranks is represented. We use this generalization to introduce a new constraint free bosonic description of truncated oscillator systems. The corresponding functional integral representations for thermodynamic quantities are given and the application to investigations of Long Rang Order in the system is discussed.Comment: latex, 8 pages, no figure

Interacting With Compatriots Abroad: The Experience of Saint-Petersburg and Practices Improvement

Interacting with foreign diaspora is a relatively new element of Russian foreign policy. Improving the legal framework and development tools in the field of interaction of the executive authority of Russian Federation with compatriots abroad has allowed the Russian regions including St. Petersburg to connect to this work, supporting the interest of compatriots to their historic homeland through the study of the Russian language, Russian culture, traditions, preservation of cultural heritage of the Russian diaspora. The theoretical basis has allowed to develop a methodological basis of the study, including the chronological method, the network method to determine the Russian world as a single transnational essence, and forecasting method. Proposals to improve the organization of St. Petersburg executive authorities, including - a recommendation to return the practice of a unified system of interested agencies in the form of programs of St. Petersburg Government “Compatriots”. Implementation of the proposals may help the efficiency of St. Petersburg executive authority with compatriots abroad, expand the foreign economic relations, actively forming a positive image of St. Petersburg and Russia in the countries of the diaspora

Quantum liquids of particles with generalized statistics

We propose a phenomenological approach to quantum liquids of particles obeying generalized statistics of a fermionic type, in the spirit of the Landau Fermi liquid theory. The approach is developed for fractional exclusion statistics. We discuss both equilibrium (specific heat, compressibility, and Pauli spin susceptibility) and nonequilibrium (current and thermal conductivities, thermopower) properties. Low temperature quantities have the same temperature dependences as for the Fermi liquid, with the coefficients depending on the statistics parameter. The novel quantum liquids provide explicit realization of systems with a non-Fermi liquid Lorentz ratio in two and more dimensions. Consistency of the theory is verified by deriving the compressibility and $f$-sum rules.Comment: 14 pages, Revtex, no figures; typos correcte

Thermodynamics for Fractional Exclusion Statistics

We discuss the thermodynamics of a gas of free particles obeying Haldane's exclusion statistics, deriving low temperature and low density expansions. For gases with a constant density of states, we derive an exact equation of state and find that temperature-dependent quantities are independent of the statistics parameter.Comment: 9 pages, Revtex, no figures. References correcte

Time-domain chirally-sensitive three-pulse coherent probes of vibrational excitons in proteins

The third order optical response of bosonic excitons is calculated using the Green's function solution of the Nonlinear Exciton Equations (NEE) which establish a quasiparticle-scattering mechanism for optical nonlinearities. Both time ordered and non ordered forms of the response function which represent time and frequency domain techniques, respectively, are derived. New components of the response tensor are predicted for isotropic ensembles of periodic chiral structures to first order in the optical wavevector. The nonlocal nonlinear response function is calculated in momentum space, where the finite exciton-exciton interaction length greatly reduces the computational effort. Applications are made to coupled anharmonic vibrations in the amide I infrared band of peptides. Chirally-sensitive and non sensitive signals for alpha helices and antiparallel beta sheets are compared.Comment: 26 pages, 6 figure

Dynamics of spin correlations in the spin-1/2 isotropic XY chain in a transverse field

Dynamic xx spin pair correlation functions for the isotropic spin-1/2 XY chain are calculated numerically for long open chains in the presence of a transverse magnetic field at finite temperature. As an application we discuss the temperature dependence of the spin-spin relaxation time in PrCl_3.Comment: 2 pages, latex, 2 figures, abstract of the paper presented at Ampere Summer School ``Applications of Magnetic Resonance in Novel Materials'' Nafplion, Greece, 3-9 September, 2000, partially published in J. Phys. A: Math. Gen. 33, 3063 (2000