Physical interpretation of the Kerr-Newman-Ernst solutions

A relation is determined between the physical quantities in the Kerr-Newman priming solution and the Kerr-Newman-Ernst solution transformed by using the Harrison solution. It is shown that this latter possesses a nonsingular horizon of events. The values obtained for the 4-potential of the electromagnetic field of the transformed solution is in a linear approximation in the magnetic field intensity.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 10, pp. 39–45, October, 1989.     

Mn site substitution of La0.67Ca0.33MnO3 with closed shell ions: Effect on magnetic transition temperature

Mn site is substituted with closed shell ions (Al, Ga, Ti, Zr and a certain combination of Zr and Al) and also with Fe and Ru ions carrying the magnetic moment (S=5/2 and 2 respectively) at a fixed concentration of 5 at %. Substitution did not change either the crystal symmetry or the oxygen stoichiometry. All substituents were found to suppress both the metal-insulator and ferromagnetic transition temperatures (T _p(ρ) and T _C, respectively) to varied extents. Two main contributions identified for the suppression are the lattice disorder arising due to difference in the ionic radii between the substituent (r _M) and the Mn³⁺ ion (r _Mn ³⁺) and in the case of the substituents carrying a magnetic moment, the type of magnetic coupling between the substituent and that of the neighboring Mn ion.     

Gravitational radiation from Coulomb collisions

The problem is considered of gravitational bremsstrahlung radiation from collisions between nonrelativistic charged particles at arbitrary values of the Born parameter ¦e₁e₂¦/hv (with exact Coulomb wave functions). It is shown that the existing estimates of this type of radiation from the solar plasma are far too high as they are based on equations for the cross section which are not applicable at the given temperature. A new estimate is derived.Translated from Izvestiya Vysshykh Uchebnykh Zavedenii, Fizika, No. 12, pp. 94–99, December, 1974.     

Finite-dimensional Grassmann algebras and structure of the equations of simple supergravity

Theoretical and Mathematical Physics -