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S. L. Cherkas

Publications and source records attributed to S. L. Cherkas.

29 records · Page 2Linked to original sources
arXiv2007

Determination of the UV cut-off from the observed value of the Universe acceleration

It is shown that using of the equation of motion of the Universe scale factor allows calculation of the contribution of the vacuum fluctuations to the acceleration of the Universe expansion. Renormalization of the equation is needed only in the case of massive particles. Under a known number of the different kinds of fundamental fields, this provides determination of momentum of the ultraviolet cut-off from the observed value of acceleration.

gr-qc↗
arXiv2006

Decelerating and accelerating back-reaction of vacuum to the Universe expansion

Back-reaction of the massless scalar field vacuum to the Universe expansion is considered. Automatic renormalization procedure based on the equations of motion instead of the Friedman equation is used to avoid the cosmological constant problem. It is found, that the vacuum tends to decelerate an expansion of Universe if the conformal acceleration of Universe is equal to zero. In contract, the vacuum acts as the true cosmological constant in Universe expanding with the present day acceleration. Estimation for third derivative of the Universe scale factor with respect to conformal time is presented.

gr-qc↗
arXiv2006

Laser in the axial electric field as a tool to search for P-, T- invariance violation

We consider rotation of polarization plane of the laser light when a gas laser is placed in a longitudinal electric field (10~kV/cm). It is shown that residual anisotropy of the laser cavity 10^{-6} and the sensitivity to the angle of polarization plane rotation about 10^{-11} -10^{-12} rad allows one to measure an electron EDM with the sensitivity about 10^{-30} e cm.

physics.optics↗
arXiv2006

Quantum evolution of the Universe in the constrained quasi-Heisenberg picture: from quanta to classics?

The quasi-Heisenberg picture of minisuperspace model is considered. The The quasi-Heisenberg picture of minisuperspace model is considered. The suggested scheme consists in quantizing of the equation of motion and interprets all observables including the Universe scale factor as the time-dependent (quasi-Heisenbeg) operators acting in the space of solutions of the Wheeler--DeWitt equation. The Klein-Gordon normalization of the wave function and corresponding to it quantization rules for the equation of motion allow a time-evolution of the mean values of operators even under constraint H=0 on the physical states of Universe. Besides, the constraint H=0 appears as the relation connecting initial values of the quasi-Heisenbeg operators at $t=0$. A stage of the inflation is considered numerically in the framework of the Wigner--Weyl phase-space formalism. For an inflationary model of the ``chaotic inflation'' type it is found that a dispersion of the Universe scale factor grows during inflation, and thus, does not vanish at the inflation end. It was found also, that the ``by hand'' introduced dependence of the cosmological constant from the scale factor in the model with a massless scalar field leads to the decrease of dispersion of the Universe scale factor. The measurement and interpretation problems arising in the framework of our approach are considered, as well.

gr-qc↗
arXiv2005

Quantum evolution of the Universe from $τ=0$ in the constrained quasi-Heisenberg picture

The Heisenberg picture of the minisuperspace model is considered. The suggested quantization scheme interprets all the observables including the Universe scale factor as the (quasi)Heisenberg operators. The operators arise as a result of the re-quantization of the Heisenberg operators that is required to obtain the hermitian theory. It is shown that the DeWitt constraint H=0 on the physical states of the Universe does not prevent a time-evolution of the (quasi)Heisenberg operators and their mean values. Mean value of an observable, which is singular in a classical theory, is also singular in a quantum case. The (quasi)Heisenberg operator equations are solved in an analytical form in a first order on the interaction constant for the quadratic inflationary potential. Operator solutions are used to evaluate the observables mean values and dispersions. A late stage of the inflation is considered numerically in the framework of the Wigner-Weyl phase-space formalism. It is found that the dispersions of the observables do not vanish at the inflation end.

gr-qc↗
arXiv2003

Quantum evolution of the Universe from $τ=0$

We have shown that DeWitt constraint H=0 on the physical states of the Universe does not prevent Heisenberg operators and its mean values to evolve with time. Mean value from observable, which is singular in classical theory, is also singular in a quantum case.

gr-qc↗
arXiv2002

Testing of CP, CPT and causality violation with the light propagation in vacuum in presence of the uniform electric and magnetic fields

We have considered the structure of the fundamental symmetry violating part of the photon refractive index in vacuum in the presence of constant electric and magnetic fields. This part of the refractive index can, in principle, contain CPT symmetry breaking terms. Some of the terms violate Lorentz invariance, whereas the others violate locality and causality. Estimates of these effects, using laser experiments are considered.

hep-ph↗
arXiv2000

Scattering of a particle with spin by atomic chain as null test of T-violating P-even magnetism

T-odd P-even long-range electromagnetic interaction of a particle of spin 1/2 with the nucleus is considered. Though matrix element of the interaction is zero for the particles on mass shell, nevertheless, null test exists for the interaction. The test consists in measuring of the spin-dependent T-odd P-even forward elastic scattering amplitude of a particle of spin 1/2 by atomic chain (axis) in a crystall.

hep-ph↗
arXiv1999

Deuteron spin oscillation and rotation as a universal method of the N-N scattering amplitude study

We consider the effects of the deuteron spin rotation and oscillations at the matter which is proportional to the real part of the deuteron spin-dependent forward scattering amplitude. That gives a possibility of a direct measurement of this quantity. Spin-dependent forward scattering amplitude of the deuteron on an unpolarized proton is discussed in terms of the Glauber multiscattering theory. This amplitude is determined by the nucleon rescattering, nonsphericity of the deuteron and spin-dependent nucleon-nucleon scattering amplitude. Thus deuteron spin oscillation phenomenon represents a method for N-N scattering amplitude investigation, including its real part, over a broad energy range.

hep-ph↗