The relation between the theory of relativity and the concept of superluminal inertial reference frame is analysed in terms of the operational definitions of spacelike, timelike, and null directions. It is concluded that such a concept does not exist inside the theory of relativity and that every consistent addition of that concept to the theory gives consequences being strange from the point of view of contemporary physics. It is also concluded that the interpretation of that concept in the literature is contradictory to the theory of relativity. The existence of that contradiction is explained here as an effect of the confusion between mappings and transformations.
Within the framework of the gauge approach to gravitation, including terms in the lagrangian quadratic in the curvature and torsion tensors, restrictions on the indefinite parameters of the lagrangians are obtained. It is shown, that the simultaneous consideration of the cosmological problem, quantisation of gravity and Birkhoff’s theorem reduces to the two 5-parametric gravitational lagrangians.
The field equations of the Brans–Dicke scalar-tensor theory are investigated. Exact vacuum solutions are given for Bianchi type-VIII and type-IX models.
Einstein’s field equations are solved in the case of Bianchi type-VI\(_0\) and type-VII\(_0\) models. In these solutions appears a particular form of the Painlevè transcendent of type III.
The standard step function approximation for the energy dependence of the continuum contribution to the cross-section for heavy quark production in e e annihilation is replaced by an approximation with a much softer energy dependence. This change is found to have little effect on the predictions from the SVZ sum rules.
It is shown that the total field energy for general solutions of the sourceless Maxwell’s equations with \(\vec E || \vec B\) is infinite. Moreover the action and/or the “pseudoscalar charge” must be infinite too in this case. Therefore the expected similarity to the instanton or meron solutions of nonabelian gauge theories is illusory.
The Breit equation for a system of two Dirac particles, which was recently represented in the tensor form, is reduced explicitly in the case of equal masses to a considerably simple system of radial equations. The vector and scalar spin-dependent central potentials ate considered. For the reduction the multipole technique is used.
A general method of derivation of conservation laws for non-local field Theories si presented. Differences in comparison with a local case are stressed. Two kinds of Lagrangians appearing in a non-local theory are examined. Canonical choice of constants of motion is made corresponding to the transformations from the conformal and gauge groups.
The dynamics of heavy ion collisions is described in a one dimensional hydrodynamic4 model. Numerical calculations are performed at 100 MeV/nucleon and 1 GeV/nucleon projectile energies. The density increase and the width of the shock front are evaluated for the compression stage. The differential cross section and the rapidity spectrum of the emitted nucleons are calculated.
