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B. I. Lev

Publications and source records attributed to B. I. Lev.

At least 19 recordsLinked to original sources
arXiv2025

Thermodynamic relation for the systems with inhomogeneous distribution of particles

For the system with inhomogeneous distribution of macroscopic parameters we obtain thermodynamic relation which depends on the spatial point (coordinate). In our approach, to obtain such a relation we use the basic ideas of the method of nonequilibrium statistical operator combined with the Hubbard-Stratonovich transformation. First of all, we define the thermodynamic relation for the system with homogeneous distribution of particles. Possible behavior peculiarities of systems with different character of interaction in nonequilibrium case are predicted. By saddle-point method we find the dominant contributions to the partition function and obtain all thermodynamic parameters of the systems with different character of interaction. The formations of saddle state in all systems of interacting particles at different temperatures and particle distributions have the same physical nature and therefore they can be described in the same way. We consider the systems with attractive and repulsive interactions as well as self-gravitating systems.

cond-mat.stat-mech↗
arXiv2024

Implications of the geometric representation of the early universe wave function

The main goal of this article is to present an algebraic approach to describing the birth and start evolution of the universe. In such an approach, it is possible to use the nature of supersymmetry in terms of the geometric representation of the wave function and propose a mechanism of spontaneous symmetry breaking of the excitations of the universe with different degrees of freedom. On this basis, it is possible to explain the origin of dark energy and matter and explain the baryonic asymmetry of the universe.

gr-qc↗
arXiv2020

Thermodynamics induced geometry of self-gravitating systems

A new approach based on a statistical operator is presented, which allows to take into account the inhomogeneous particle distribution induced by gravitational interaction. This method uses the saddle point procedure to find the dominant contribution to the statistical sum and allows to obtain all thermodynamic relations of self-gravitating systems. Based on thermodynamic relations, a description of thermodynamically induced geometry of matter distribution was proposed. Equations corresponding to the extremum of the statistical sum completely reproduce the well-known equations of the general theory of relativity.

physics.gen-ph↗
arXiv2019

Vacuum friction of uniformly accelerated detector

The analysis of uniformly longitudinally extended detector is performed and it is shown that the response of such a detector does not differ from the response of the Unruh detector, but the its excitation is caused not by the thermal bath, but by interaction with the fluctuations of the quantum field by virtual quanta.

quant-ph↗
arXiv2019

Statistical description of the Universe formation

Statistical description of the Universe as non-equilibrium system has been proposed. Based on two fundamental principles, i.e., the law of increasing entropy and the principle of minimum energy of the system and try to answer the question of what the reasons of the Big Bang and the birth of the Universe were.

physics.gen-ph↗
arXiv2019

Internal magnetic field distribution in plasmas

We calculate stationary probability distribution of magnetic field, generated by moving charges of plasma environment, and stationary probability distribution of force, acting on charged particle in this environment, with magnetic interaction taken into account. While the former happens to be the Holtsmark distribution, the latter is a modified Holtsmark distribution. In contrast to prior works, we did no assumptions on the velocity distribution function and thus obtained results should be applicable to wider spectrum of models. Presented results can be experimentally verified through studies of Zeeman effect or movement of small charged Brownian particles in plasma.

cond-mat.soft↗
arXiv2017

Collective diffusion of a colloidal particles in a liquid crystal

The collective diffusion effects in system of a colloidal particles in a liquid crystal has been proposed. In this article described peculiarity of collective diffusion colloidal particles in a liquid crystal, which can be observe experimentally. The diffusion coefficient should be crucial dependence from temperature and concentration of particles. In system colloidal particles arise from the elastic distortion of the elastic director field the inter-particle interaction. These interaction can cause nontrivial collective behavior, as the results the non-monotonic dependence collective diffusion. Are predicted a nontrivial behavior collective diffusion of colloidal particles in a liquid crystal.

cond-mat.soft↗
arXiv2017

Peculiarities of oscillator with nonlinear cordinate-dependent mass

A nonlinear model of the scalar field with a coupling between the field and its gradient is developed. It is shown, that such model is suitable for the description of phase transition accompanied by formation of spatial inhomogeneous distribution of the order parameter. The proposed model is analogous the mechanical nonlinear oscillator with the coordinate-dependent mass or velocity-dependent elastic module. Besides, for some value of energy the model under consideration possesses exact analytical solution. We assume that this model can related to the spinodal decomposition, quark confinement, or cosmological scenario. All predictions can be verified experimentally.

cond-mat.stat-mech↗
arXiv2016

Inhomogeneous distribution of particles and temperature in self-gravitating system

Self-gravitating system are non-equilibrium a priory. A new approach is proposed, which employs a non-equilibrium statistical operator into account inhomogeneous distribution of particles and temperature. The method involves the saddle - point procedure to find the dominant contribution to the partition function and thus to obtain all thermodynamic parameters of the system. Probable peculiar features in the behavior of self-gravitating system are considered for various condition. The equation of state for self-gravitating system has been obtained. A new length of statistical instability and parameter of the spatial inhomogeneous distribution of particles and temperature are obtained for real gravitating system.

cond-mat.stat-mech↗
arXiv2015

Free energy analysis for a system of interacting particles arranged in Bravais lattice

We propose a method of free energy calculation for a system of interacting particles arranged in a Bravais lattice. It will be shown how to treat divergences for infinite unbounded systems with "catastrophic" potetntials like Coulomb and compare two of them. Besides, we show that current method may be used not only for essentially classical systems, but for some quantum as well. Two systems are considered: grains in dusty plasma and electrons on the liquid-helium surface. For dusty-plasma parameters of grain's lattice are calculated by numerical solution of obtained equations. Electrons on the liquid-helium surface are analyzed to get localization distance. Besides, conditions for existence of electron lattice are found.

cond-mat.stat-mech↗
arXiv2015

The model of a hypothetical room-temperature superconductor

The model of hypothetical superconductivity, where the energy gap asymptotically approaches zero as temperature increases, has been proposed. Formally the critical temperature of such a superconductor is equal to infinity. For practical realization of the hypothesis a superconducting material with such properties is predicted.

cond-mat.supr-con↗
arXiv2014

Surface induced structures in nematic liquid crystal colloids

We predict theoretically the existence of a class of colloidal structures in nematic liquid crystal (NLC) cells, which are induced by surface patterns on the plates of the cell (like cells with UV-irradiated polyimide surfaces using micron size masks). These bulk structures arise from non-zero boundary conditions for the director distortions at the confining surfaces. In particular, we demonstrate that quadrupole spherical particles (like spheres with boojums or Saturn-ring director configurations) form a square lattice inside a planar NLC cell, which has checkerboard patterns on both its plates.

cond-mat.soft↗
arXiv2014

Analytical calculation of the Stokes drag of the spherical particle in a nematic liquid crystal

As an approach to the motion of particles in an anisotropic liquid, we analytically study the Stokes drag of spherical particles in a nematic liquid crystal. The Stokes drag of spherical particles for a general anisotropic case is derived in terms of multipoles. In the case of weak anchoring, we use the well-known distribution of the elastic director field around the spherical particle. In the case of strong anchoring, the multipole expansion may be also used by modifying the size of a particle to the size of the deformation coating. For the case of zero anchoring (uniform director field) we found that the viscosities along the director $η_{\parallel}$ and perpendicular direction $η_{\perp}$ are almost the same, which is quite reasonable because in this case the liquid behaves as isotropic. In the case of non-zero anchoring, the general ratio $η_{\parallel}/η_{\perp}$ is about 2 which is satisfied by experimental observations.

cond-mat.soft↗
arXiv2014

The statistical description of the electron system on the liquid helium surface

It is known that homogeneous distribution of particles in Coulomb-like systems can be unstable, and spatially inhomogeneous structures can be formed. A simple method for describing such inhomogeneous systems and obtaining spacial distributions of electron density is proposed and applied to the case of two-dimensional electron systems on surface of liquid helium. A free energy functional for the model in mean field approximation is obtained. Creation of various types of structures, such as long-range periodical modulation and multi-electron dimples, is predicted by minimizing this functional.

cond-mat.stat-mech↗
arXiv2013

Elastic monopoles and external torques in nematic liquid crystal colloids

Up to now it is commonly believed that a colloidal particle suspended in a nematic liquid crystal never produces elastic monopoles because this violates the mechanical equilibrium condition. And the only way to obtain deformations of director field falling off with distance as r^{-1} is to exert an external torque Γ_{ext} on the colloid \cite{de_Gennes}. In this paper we demonstrate that this statement is not quite correct and elastic monopoles, as well as dipoles and quadrupoles, can be induced without any external influence just by the particle itself. A behavior of a spherical colloidal particle with asymmetric anchoring strength distribution is considered theoretically. It is demonstrated that such a particle when suspended in a nematic host can produce director deformations decreasing as $r^{-1}$, i.e. elastic monopoles, by itself without any external influence.

cond-mat.soft↗
arXiv2013

The ground state and the character of the interaction between a colloidal particles in a liquid crystals

In this article is proposed the general approach to determination the character of the interaction between colloidal particles in a different liquid crystals. The main idea of this approach are in the presentation of the colloidal particle as sours of the possible deformation of the ground state of the director field. The ground state of liquid crystal imposes restrictions on the possible deformations and as result determine the character of the interaction between the colloidal particles. Based on this approach the Coulomb like interaction between dipole particles in a cholesteric liquid crystal and changing of the character of the interaction in a smactic liquid crystal has been predicted.

cond-mat.soft↗
arXiv2013

Effect of impurities with retarded interaction with quasiparticles upon critical temperature of s-wave superconductor

Generalization of a disordered metal's theory has been proposed when scattering of quasiparticles by impurities is caused with a retarded interaction. It was shown that in this case Anderson's theorem was violated in the sense that embedding of the impurities in s-wave superconductor increases its critical temperature. The increasing depends on parameters of the metal, impurities and their concentration. At a specific relation between the parameters the critical temperature of the dirty superconductor can essentially exceed critical temperature of pure one up to room temperature. Thus the impurities catalyze superconductivity in an originally low-temperature superconductor.

cond-mat.supr-con↗