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Theoretical and mathematical physics

The role of gravitational fields in stellar physics and the evolution of the universe

The role of gravitational fields in stellar physics and the evolution of the universe

Yu.M. Loskutov

Moscow University Physics Bulletin 2013. 68. N 3. P. 177

The assertion that the gravitational field is a material matter with all the attributes of any other matter (energy density, pressure, four-velocity of the elements, and interaction of the elements with one another and with other material objects) is shown to modify the physical notions of the dynamics of bodies, Riemannian space, the internal structure of a star, the evolution of the universe, etc. Instead of the black holes of the geometrized approach to the theory of gravitation, we have objects with a researchable internal structure, which explains, e.g., the observed attenuation of the boundaries of the emission spectra of matter that falls into supermassive objects. The problem of dark matter is explained. The generally accepted understanding of matter (without adding any free parameters to the theory) is shown to allow a scenario of the universe that is permanently pulsating between the states of the maximum and minimum density of matter. The scenario is shown to be in good agreement with the recent observational data.

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Theoretical and mathematical physics

The generalized van Laar approximation for free energy

The generalized van Laar approximation for free energy

P.N. Nikolaev

Moscow University Physics Bulletin 2013. 68. N 3. P. 196

The van Laar equation for the uniform substance phase is analyzed. Based on this, an expression for free energy is found. The structure of the expression allowed us to create a method for determining the free energy in an arbitrary order of the perturbation theory. A generalized equation for free energy is derived based on the using thermodynamic perturbation theory and the accelerated method of convergence of the series of the perturbation theory. This expression agrees well with the asymptotic behavior of the free energy and with the known experimental data. It can be successfully used to describe the behavior of the substance in a super-critical region, as well as to investigate the metastable phase. It is shown that the expression for free energy can be used for a broad class of substances.

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Hydrodynamic solutions of the generalized Boltzmann-Enskog equation

Hydrodynamic solutions of the generalized Boltzmann-Enskog equation

N.G. Inozemtseva, I.I. Maslennikov

Moscow University Physics Bulletin 2013. 68. N 3. P. 201

The properties of a kinetic equation are considered for systems of particles with a binary interaction containing a “hard core” and a far-range component. The solutions that correspond to periodic small perturbations of the distribution function are investigated.

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Physics of nuclei and elementary particles

QCD sum rules for the coupling constants of vector mesons to octet baryons

QCD sum rules for the coupling constants of vector mesons to octet baryons

V.S. Zamiralov$^1$, A. Ozpineci, G. Erkol

Moscow University Physics Bulletin 2013. 68. N 3. P. 205

The QCD sum rules on the light cone proposed by Wang for the coupling constants of the ρ meson are generalized to the vector mesons ω and φ and all octet baryons, the Λ-hyperon included. A comparison with other results is given.

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Radiophysics, electronics, acoustics

Acoustic radiation of moving dipoles and axial quadrupoles consisting of discrete antiphased monopoles

Acoustic radiation of moving dipoles and axial quadrupoles consisting of discrete antiphased monopoles

E.Ya. Bubnov

Moscow University Physics Bulletin 2013. 68. N 3. P. 210

An acoustic field generated by a moving dipole that consists of two antiphased monopoles and an axial quadrupole represented as a combination of four discrete monopoles with corresponding phases was analyzed. It was revealed that the angular distribution of the pressure amplitude of the distributed source depends on the additional phase incursion between interfering waves due to the anisotropic character of the medium. The angular characteristics of the pressure amplitude of the distributed dipole and quadrupole, which depend on the orientation and velocity of their motion, were mathematically simulated. The results were compared with the conclusions drawn by other researchers.

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Condensed matter physics

2D bifurcations in a system of interacting quantum molecules in a metamaterial matrix

2D bifurcations in a system of interacting quantum molecules in a metamaterial matrix

V.Ch. Zhukovsky$^1$, V.D. Krevchik$^2$, M.B. Semenov$^2$, R.V. Zaitsev$^2$, A.K. Aryngazin$^3$, K. Yamamoto

Moscow University Physics Bulletin 2013. 68. N 3. P. 217

The influence of an electric field on 1D and 2D tunneling in a quantum molecule located in dielectric and metamaterial (with effective negative permittivity) matrices at a finite temperature has been theoretically investigated within the one-instanton approximation. It is shown that the stable mode of 2D bifurcations in a metamaterial matrix can be implemented in a much narrower range of parameters in comparison with conventional dielectric matrices. The dependence of the probability of 1D dissipative tunneling on the strength of an external electric field is qualitatively compared with the experimental tunnel I-V characteristic of semiconductor (InAs/GaAs) quantum dots.

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Lamellar phases of polymers with unusual physical and mechanical properties

Lamellar phases of polymers with unusual physical and mechanical properties

A.R. Khamidullin$^1$, A.N. Chuvyrov$^1$, Yu.A. Lebedev$^2$, V.D. Sitdikov

Moscow University Physics Bulletin 2013. 68. N 3. P. 225

Structural transitions that occur in polymers subjected to simple uniaxial tensile deformation are described for the first time. The behavior of folded nanocrystallites with initial sizes of 28×28×17 nm is most interesting. Their thicknesses strongly decrease upon deformation (from 17 nm to less than 10 nm), whereas the longitudinal sizes change only slightly. This gradual flattening of nanoclusters leads to their dislocation melting (as an intermediate stage of the phase transitions predicted by Kosterlitz and Thouless). It is shown by the methods of pole figures and atomic-force microscopy that screw dislocations are spontaneously formed in the region of elastic-plastic deformation to decelerate the first-order phase transition of melting type and that the polymer forms a new lamellar spatially inhomogeneous phase with unusual physical and mechanical properties.

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Investigation of polar and nonpolar ordering in a smectic liquid crystal layer

Investigation of polar and nonpolar ordering in a smectic liquid crystal layer

M.S. Romashin, A.V. Emelyanenko

Moscow University Physics Bulletin 2013. 68. N 3. P. 249

A molecular-statistical theory that describes a smectic layer where short molecular axes have both polar and nonpolar orders has been developed. Several types of dependences of each order parameter on temperature and external field were obtained, and all possible phase states of the layered structure were determined.

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The covariant approach in the dynamic theory of resonant X-ray diffraction

The covariant approach in the dynamic theory of resonant X-ray diffraction

A.P. Oreshko

Moscow University Physics Bulletin 2013. 68. N 3. P. 254

The main equations of the dynamic theory of X-ray synchrotron radiation resonant diffraction were obtained based on direct (coordinate-free) methods of tensor calculus.

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Spatial and temporal effects upon deposition of particles onto thin films of silicon dioxide produced using high-energy deposition processes

Spatial and temporal effects upon deposition of particles onto thin films of silicon dioxide produced using high-energy deposition processes

F.V. Grogoriev, V.B. Sulimov, O.A. Kondakova, I.V. Kochikov, A.V. Tikhonravov

Moscow University Physics Bulletin 2013. 68. N 3. P. 259

The interaction of deposited atoms with a silicon dioxide film is simulated for the case of using high-energy processes for the deposition of optical nanocoatings. The method of molecular dynamics with a classical force field is used for describing the interaction between the atoms. The characteristic time of fast relaxation of the kinetic energy of the deposited atom and the characteristic depth of its penetration into the film are estimated. It is shown that the angular distribution of the velocities of the deposited atoms is significant for the formation of a coating.

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Biophysics and medical physics

Investigation of the rotational diffusion of the Rose Bengal fluorescent nanomarker in human serum albumin solutions

Investigation of the rotational diffusion of the Rose Bengal fluorescent nanomarker in human serum albumin solutions

I.M. Vlasova, D.V. Polynskii, A.A. Vlasov, A.M. Saletsky

Moscow University Physics Bulletin 2013. 68. N 3. P. 231

The polarized fluorescence of the Rose Bengal fluorescent nanomarker in HSA solutions was investigated and parameters of its rotational diffusion were calculated. The increase in the degree of fluorescence polarization, rotational relaxation time, and the effective hydrodynamic radius of Rose Bengal, as well as the decrease of the rotational diffusion coefficient in HSA solutions, were found. The effects of the electronegativity of atoms in the structure of the nanomarker on the parameters of its rotational diffusion were established based on comparison of Rose Bengal with other nanomarkers of the homologous family.

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Astronomy, astrophysics, and cosmology

Estimating the apparent motions of extragalactic radio sources

Estimating the apparent motions of extragalactic radio sources

N.A. Voronkov$^1$, V.E. Zharov$^2$

Moscow University Physics Bulletin 2013. 68. N 3. P. 235

The apparent motions of 573 extragalactic radio sources are estimated. For this purpose, we analyzed the data that were obtained during 3193 series of observations using very-long baseline radio interferometry (VLBI) from 1984 to 2010. To find a solution, the least-squares method with constraints is applied. It is shown that most radio sources (including defining sources) are characterized by significant apparent motions. Since the stability of the celestial reference system is due to the absence of net rotation (no-net-rotation condition) relative to the defining sources, a change in their coordinates leads to the rotation of the celestial coordinate system (CCS). Owing to this, we believe that the apparent motions of radio sources must be given in catalogs.

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Physics of Earth, atmosphere, and hydrosphere

Magnetic properties and structure of Fe$_{2-x}$Mg$_x$CrO$_4$ chromites

Magnetic properties and structure of Fe$_{2-x}$Mg$_x$CrO$_4$ chromites

V.I. Maksimochkin$^1$, R.R. Gubaidullin$^2$, M.Ya. Gareeva$^2$

Moscow University Physics Bulletin 2013. 68. N 3. P. 241

The structural and magnetic properties of Fe$_{2-x}$Mg$_x$CrO$_4$ chromite synthesized by the ceramic method to receive analogs of natural minerals and to solve the rock magnetism problems are investigated. The dependences of cubic-lattice parameters and magnetic characteristics on composition, with slight deviation from linearity, are obtained. It is established in the course of experiments related to the partial thermal remanent magnetization in weak fields that some compositions are characterized by self-reversal under sample heating to 600°C in air. It is suggested that the self-reversal is caused by a nonuniform distribution of cations in chromite structure and phase transformation under oxidation.

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Thermal neutrons from the earth’s surface during the upper and lower transits of the moon and the sun on new moon and full moon days

Thermal neutrons from the earth’s surface during the upper and lower transits of the moon and the sun on new moon and full moon days

N.N. Volodichev, O.Yu. Nechaev, E.A. Sigaeva

Moscow University Physics Bulletin 2013. 68. N 3. P. 263

The times of increases in the thermal neutron flux from the earth are compared with the passages of the moon and the sun at the longitudes of the observation sites on July 26, 1991, July 27, 1991, July 12, 1995, July 29, 1996, and July 21, 1997 (the upper and lower transits of the moon and the sun). The results confirm the role of tidal forces in the generation of thermal neutron fluxes from the earth’s surface. The study uses the astronomical annuals of the Russian Academy of Sciences for the corresponding years.

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