118808799
Introduction to the relativistic string theory
This book presents a systematic and detailed account of the classical and quantum theory of the relativistic string and some of its modifications. Main attention is paid to the first-quantized string theory with possible applications to the string models of hadrons as well as to the superstring approach to unifications of all the fundamental interactions in the elementary particle physics and to the “cosmic” strings. Some new aspects are provided such as the consideration of the string in an external electromagnetic field and in the space-time of constant curvature (the de Sitter universe), the relativistic string loaded by point-like masses and the Cartan method for describing the classical string dynamics. The relativistic membranes and p-branes are also considered briefly. The book is sufficiently self-contained and can be considered as an introduction to this new and fast developing branch of the elementary particle physics.
16432431
Functionals linear in curvature and protein folding
The free energy of globular protein chain is considered to be a functional defined on smooth curves in three dimensional Euclidean space. From the requirement of geometrical invariance, together with basic facts on conformation of helical proteins and dynamical characteristics of the protein chains, we are able to determine, in a unique way, the exact form of the free energy functional. Namely, the free energy density should be a linear function of the curvature of curves E-mail: feoli@unisannio.it; fax: +39089965275 E-mail: nestr@thsun1.jinr.ru E-mail: scarpetta@sa.infn.it
29489956
Direct mode summation for the Casimir energy of a solid ball
The Casimir energy of a solid ball placed in an infinite medium is calculated by a direct frequency summation using the contour integration. It is assumed that the permittivity and permeability of the ball and medium satisfy the condition . After deriving the general expression for the Casimir energy, a compact ball is considered when . Calculations are carried out which are of the first order in and take account of the fifth-order terms in the uniform asymptotic expansion of the Bessel functions involved. The implication of the results to attempt to explain sonoluminescence via the Casimir effect is briefly discussed.
204934704
Some recent results in calculating the Casimir energy at zero and finite temperature
The survey summarizes briefly the results obtained recently in the Casimir effect studies considering the following subjects: i) account of the material characteristics of the media and their influence on the vacuum energy (for example, dilute dielectric ball); ii) application of the spectral geometry methods for investigating the vacuum energy of quantized fields with the goal to gain some insight, specifically, in the geometrical origin of the divergences that enter the vacuum energy and to develop the relevant renormalization procedure; iii) universal method for calculating the high temperature dependence of the Casimir energy in terms of heat kernel coefficients.
121750447
Derivation of an expression for a Hamiltonian functional integral in theories with first and second class constraints
A Hamiltonian functional integral in theories with first and second class constraints (both stationary and nonstationary) is derived in a simple and consistent manner. The gauge conditions need not be in involution and may contain the time explicitly. In contrast to other studies, much attention is devoted to the proof of the Hamiltonicity of the theory on the physical submanifold Gamma* of the phase space Gamma. It is shown that ..delta../sup -1/, where D is the Faddeev-Popov determinant, is simply the volume element of the subspace Gamma = Gamma/Gamma* in noncanonical coordinates determined by the constraints and gauge conditions. It is proved that the expression for the functional integral is invariant under finite transformations of the gauge conditions.
15884859
Casimir energy of a nonuniform string
The Casimir energy of a non-uniform string built up from two pieces with different speed of sound is calculated. A standard procedure of subtracting the energy of an infinite uniform string is applied, the subtraction being interpreted as the renormalization of the string tension. It is shown that in the case of a homogeneous string this method is completely equivalent to the zeta renormalization.
122920106
SUM RULES AND PION FORM FACTOR IN QCD
116346471
APPLICATION OF NUCLEAR THEORY METHODS TO NEW FAMILY OF FERMI SYSTEM
Duo to a remarkable progress in experimental techniques, the new family of .small Fermi systems (SFS) (metal clusters, fullerencs, helium clusters and quantum dots) was discovered about ten years ago. As was established, those Fermi systems have a striking similarity with atomic nuclei (see re­views and conference proceedings [1-9]). The most remarkable feature of now SFS is that they possess a mean field of the same kind as in atomic iniclci which allows one to investigate SFS by nuclear theory methods. If recent investigations of SFS have mainly been limited to atoms and atomic nuclei, our present possibilities have become much wider, We have really obtained a good chance for studying both a common behavior of SFS and a wonderful variety of their properties. In the present paper, the particular properties of the new SFS as well as the application of nuclear physics methods to their description are briefly reviewed. The properties of the new SFS and atomic nuclei are continually compared. The main attention is paid to metal clusters (MC) or, more precisely, to E\ giant resonances (GR) in this system. Iri Sec.2, the sketch of basic properties of MC as well as the perspectives of their investigation arc given. Sec.3 is devoted to the description of E\ GR in MC, In Sec.3 the properties of fullerencs, helium clusters and quantum dots are outlined. In Sec.4 the conclusions are presented.
125323640
{QCD} Sum Rule Analysis of the Pion Form-factor Behavior in Small $Q^2$ Region
120836438
Quantum gravitational effects in an isotropic universe
Effects of vacuum polarization by an external gravitational field in a system of spinor, scalar, and massive vector particles are considered in the model of conformally flat space-time. Expressions are obtained for the radiative corrections, and the part they play in gravitational theory is analyzed in the limits of weak (Vertical BarR/sup k//sub i/Vertical Bar m/sup 2/) gravitational fields. The Appendix gives expressions for the rate of spontaneous production of real particles by a strong gravitational field and the energy-momentum tensor of real particles in the ultrarelativistic limit; a law of increase of the entropy of an ultrarelativistic medium is also formulated.
125654630
Pion Form-factor and {QCD} Sum Rules