abstract

For a particle constrained in the internal variables by relations of the light cone type, we derive generators of motion within the framework of the Sudarshan, Mukunda and Goldberg formalism as an extended form of the Dirac generator procedure for constrained Hamiltonian dynamics. It is shown that the realization of the Poincaré group obtained for this particle is compatible with the Lie algebra of the de Sitter group SO(2, 1), proper to rotator models. Characteristic features of a relativistic rotator are then demonstrated on evolution equations for dynamical variables.

abstract

The dynamics of the full class of homogeneous \(N=1\), \(d=11\) supergravity world models is investigated. By using the classification of Lie algebras of Lie groups which act simply transitively on 6- and 7-dimensional compact spaces some conclusions are drawn concerning the non-existence of the chaotic regime near the singularity. This is illustrated with some new solutions having a richer structure of the microspace. The significance of known solutions is briefly discussed.

abstract

Papers of Kalinkin, Shmonin et al. describing cumulative meson production in hadron–nuclear and nucleus–nuclear interactions have been analysed, and the results of this critical analysis are given. It is shown that there are many errors in the calculation formulae. The attempts to reproduce the numerical results of the authors from their formulae and their computer programme gave no positive results.

abstract

The wave function suggested from the statistical model has been used as an input to estimate the charm and bottom quark masses \(m_{\rm c}\) and \(m_{\rm b}\) in the context of the sum rules. The moment ratio, \(R_n\), from SVZ moments and the photo-production cross-sections for S-state mesons in \(\psi ({\rm c}\bar {\rm c})\) and \(\Upsilon ({\rm b} \bar {\rm b})\) families have been computed with interesting predictions.

abstract

We investigate one-loop effects at finite temperatures for an open Robertson–Walker Universe, and v e obtain formulae for a scalar field Coleman-Weinterg potential. The meaning of non-zero temperature and negative curvature for the space-time topology \(R^1 \times PS^3\) is discussed. Zero-point fluctuation of energy are determined.

abstract

A model of coherent soft gluon production at large angle (string effect) admitting parton-like interpretation is proposed. Comparison with earlier approaches used in Monte-Carlo simulations is made.

abstract

Using the technique of nonlinear realizations we discuss the structure of the chiral effective Lagrangians. The only restrictions on the possible form of the Lagrangian we consider are phenomenological ones: the Vector Meson Dominance (VMD), universality and KSFR relation. We consider in more detail the SU(2) case (nonanomalous part). From this general point of view we review a number of Lagrangians recently proposed in literature.