CPT violation and particle-antiparticle asymmetry in cosmology

General features of generation of the cosmological charge asymmetry in CPT noninvariant world are discussed. If the effects of CPT violationmanifest themselves only inmass differences of particles and antiparticles, the baryon asymmetry of the Universe hardly can be explained solely by breaking of CPT invariance. However, CPT noninvariant theories may lead to a new effect of distorting the usual equilibrium distributions. If this takes place, CPT violation may explain the baryon asymmetry of the Universe.     

Enhancement of fluorescence of porous silicon upon saturation by liquid crystal

The fluorescence of samples of porous silicon of various morphologies that are filled with a liquid crystal (LC), n-pentyl-n′-cyanobiphenyl (5CB), is studied. The fluorescence spectra of the sample, along with the long-wavelength band of porous silicon with a maximum in the range 627–667 nm, exhibit a short-wavelength band of 5CB with a maximum in the range 385–410 nm. The radiative relaxation times of porous silicon and 5CB lie in the micro- and nanosecond ranges, respectively. It is found that the filling of pores with 5CB enhances the fluorescence of porous silicon by two to three times. This enhancement is caused by non-radiative energy transfer from 5CB to the porous matrix as a result of efficient interactions between LC molecules and pore walls. Using IR spectroscopy, it is shown that the formation of hydrogen bonds between cyano groups of 5CB molecules and silanol groups of pore surface is the predominant type of these interactions. A transfer mechanism is suggested according to which excited associates of 5CB molecules transfer their energy via surface channels to excitons of porous silicon, enhancing its fluorescence.     

Cosmology and new physics

A comparison of the standard models in particle physics and in cosmology demonstrates that they are not compatible, though both are well established. The basics of modern cosmology are briefly reviewed. It is argued that the measurements of the main cosmological parameters are achieved through many independent physical phenomena and this minimizes possible interpretation errors. It is shown that astronomy demands new physics beyond the frameworks of the (minimal) standard model in particle physics. More revolutionary modifications of the basic principles of the theory are also discussed. The text was submitted by the authors in English.     

Is LaFeAsO1-xFx an electron-phonon superconductor?

In this Letter, we calculate the electron-phonon coupling of the newly discovered superconductor LaFeAsO1-xFx using linear response. For pure LaFeAsO, the calculated electron-phonon coupling constant lambda=0.21 and logarithmic-averaged frequency omegaln=206 K give a maximum Tc of 0.8 K, using the standard Migdal-Eliashberg theory. For the F-doped compounds, we predict even smaller coupling constants. To reproduce the experimental Tc, a 5-6 times larger coupling constant would be needed. Our results indicate that electron-phonon coupling is not sufficient to explain superconductivity in the whole family of Fe-As-based superconductors, probably due to the importance of strong-correlation effects.     

Application of the High-Speed Photography Technique to Study Pulsed Vacuum Arc Plasma in a Short Gap

Physics of Atomic Nuclei - We studied the process of switching a short vacuum gap, initiated by an auxiliary discharge along the surface of the dielectric by registration images using an...     

Piezoelectric Properties of 2D Nanoallotropes of Boron Nitride

Physics of the Solid State - The independent components of the tensor of piezoelectric moduli are calculated for various 2D nanoallotropes of boron nitride. The principle of the proposed...     

Monitoring of the Kα–Kβ Spectrum of a Micropinch in an Iron Plasma

JETP Letters - The variation of the Kα–Kβ spectrum of a micropinch in an iron plasma of a high-current vacuum spark has been studied at detection in a single discharge using a...     

Condensation of charged bosons in plasma physics and cosmology

We consider the screening of impurities in plasma with a Bose-Einstein condensate of electrically charged bosons and show that the screened potential is drastically different from the usual Debye potential. The polarization operator of photons in plasma acquires infrared singular terms at small photon momentum, and the screened potential drops down as a power of distance and even has an oscillating behavior, similar to the Friedel oscillations in plasma with degenerate fermions. We also discuss the magnetic properties of the cosmological plasma with condensed W bosons and show that W bosons condense in the ferromagnetic state. This could lead to spontaneous magnetization of the primeval plasma. The created magnetic fields may seed galactic and intergalactic magnetic fields observed in the present-day Universe.