abstract

The structure of Berry’s phase for time-reversal invariant systems is reviewed. The method of constructing general “spin” Hamiltonians with quaternionic Berry’s a holonomy is presented.

abstract

Quantum field theory of real massless scalar field in two-dimensional de Sitter space-time is considered. The scalar product in the subspace of pure Coulomb states is decomposed into irreducible unitary representations of the three-dimensional proper ortochronous Lorentz group. It is shown that the Coulomb field contains representations from the main series if the “fine structure constant” (defined in the text) \(\alpha \gt 1\). If \(0 \lt \alpha \lt 1\), there is additionally a representation from the supplementary series. The eigenvalue of the Casimir operator for this representation is \(1/4\ \alpha (2 - \alpha )\).

abstract

Recently, the familiar analogy between the time evolution of an isolated system and the thermal equilibrium of a system with a thermostat led us to the hypothesis of a “temporal equilibrium” of any so called isolated system with the physical space-time. Then, small virtual deviations from such an equilibrium imply a nonunitary extension of the quantum state equation and, in consequence, a tiny unitarity defect of the S matrix. Another consequence of our conjecture is the possibility that the hypothetic Big Bang of the universe determined the absolute zero of cosmic time, an analogue of the infinite value of absolute temperature.

abstract

The spontaneous symmetry breaking theory of gravity is examined, assuming that the vacuum expectation value of the standard model Higgs is also responsible for the generation of the Planck mass. In this model the physical Higgs couples only with gravitational strength to matter. At presently accessible energies the theory is indistinguishable from the standard model without Higgs boson and is in agreement with all existing data. It provides therefore a viable alternative to the standard model coupled to ordinary Einstein gravity. At energies above the Fermi scale new dynamics should occur.

abstract

The different mass parameters are studied in the frame of nuclear fission theory. The mass asymmetry and the separation between the two fragments are used as two collective coordinates in the asymmetric two-center shell model. The different mass parameters in the case of fission of the \(^{238}\)U nucleus are calculated with a temperature dependence. The mass parameters are also studied in terms of the mass number changes for different nuclei. Analytical expression of the mass parameter are obtained using the cranking model. Numerical calculations are carried out for the mass parameters with different temperatures and for different nuclei. The obtained results show the importance of including the temperature and the effect of the mass numbers on the different mass parameters.

abstract

The experimental excitation function of the \(^{56}\)Fe\((n, p)^{56}\)Mn reaction was compared with that calculated in the frame of statistical model. A role of the GDR excitation as a doorway state was analyzed.

abstract

The distributions of differential cross sections for backward angles in case of three (\(^{28,29,30}\)Si) silicon isotopes were measured for five energies around 27 MeV. The comparison between existing data and measured data was done. Quantitative analysis of the data was made.

abstract

An effective chiral model which describes properties of a single baryon predicts that the quark matter relevant to neutron stars, close to the deconfinement density, is in a chirally broken phase. We find for the SU(2) model that pion-condensed up and down quark matter is preferred energetically at neutron star densities. It exhibits spin ordering and can possess a permanent magnetization. The equation of state of quark matter with chiral condensate is very well approximated by the bag model equation of state with suitably chosen parameters. We study quark cores inside neutron stars in this model using realistic nucleon equations of state. The biggest quark core corresponds to the second order phase transition to quark matter. Magnetic moment of the pion-condensed quark core is calculated.

abstract

A brief review of recent research on soliton and black hole solutions of Einstein’s equations with nonlinear field sources is presented and some open questions are pointed out.