Vacuum energy induced by an impenetrable flux tube of finite radius

We consider the effect of the magnetic field background in the form of a tube of the finite transverse size on the vacuum of the quantized charged massive scalar field which is subject to the Dirichlet boundary condition at the edge of the tube. The vacuum energy is induced, being periodic in the value of the magnetic flux enclosed in the tube. Our previous study in J. Phys. A: Vol.43, 175401 (2010) is extended to the case of smaller radius of the tube and larger distances from it. The dependence of the vacuum energy density on the distance from the tube and on the coupling to the space-time curvature scalar is comprehensively analyzed.Comment: 11 pages, 8 figures, journal version, abstract extended. arXiv admin note: substantial text overlap with arXiv:0911.287

Semiclassical treatment of logarithmic perturbation theory

The explicit semiclassical treatment of logarithmic perturbation theory for the nonrelativistic bound states problem is developed. Based upon $\hbar$-expansions and suitable quantization conditions a new procedure for deriving perturbation expansions for the one-dimensional anharmonic oscillator is offered. Avoiding disadvantages of the standard approach, new handy recursion formulae with the same simple form both for ground and exited states have been obtained. As an example, the perturbation expansions for the energy eigenvalues of the harmonic oscillator perturbed by $\lambda x^{6}$ are considered.Comment: 6 pages, LATEX 2.09 using IOP style

Langmuir wave linear evolution in inhomogeneous nonstationary anisotropic plasma

Equations describing the linear evolution of a non-dissipative Langmuir wave in inhomogeneous nonstationary anisotropic plasma without magnetic field are derived in the geometrical optics approximation. A continuity equation is obtained for the wave action density, and the conditions for the action conservation are formulated. In homogeneous plasma, the wave field E universally scales with the electron density N as E ~ N^{3/4}, whereas the wavevector evolution varies depending on the wave geometry

Polarization of the vacuum of a quantized scalar field by an impenetrable magnetic vortex of finite thickness

We consider the effect of the magnetic field background in the form of a tube of the finite transverse size on the vacuum of the quantized charged massive scalar field which is subject to the Dirichlet boundary condition at the tube. It is shown that, if the Compton wavelength associated with the scalar field exceeds considerably the transverse size of the tube, then the vacuum energy which is finite and periodic in the value of the magnetic flux enclosed in the tube is induced on a plane transverse to the tube. Some consequences for generic features of the vacuum polarization in the cosmic-string background are discussed.Comment: 13 pages, 10 figures, journal version, minor changes, some references adde

Carcinogenicity Screening of Chemicals Using Positron Annihilation Spectroscopy

Chemical carcinogens are the main cause of cancer. Many thousands of new chemicals are synthesized annually in the world, unknown part of them is carcinogens. There are several methods, which are currently used for testing carcinogenicity. The fastest arephysicochemical methods. We suggest the method of fast carcinogen screening using the positron annihilation spectroscopy (PAS). It is based on the fact that the presence of carcinogens, being strong electrophiles, significantly decreases positronium (Ps) formation probability. This quantity can be measured by means of conventional PAS techniques: positron annihilation lifetime spectroscopy (PALS), angular correlation of annihilation radiation (ACAR) or Doppler broadening of annihilation radiation (DBAR). It is also possible to evaluate anti-carcinogenic properties of chemicals using the anti-inhibition effect of Ps formation. Keywords: carcinogen, electrophilicity, positron annihilation spectroscopy, positroniu