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Dorkin S.M.,International University of Nature, Society and Man «Dubna» | Kaptari L.P.,Helmholtz Center Dresden | Hilger T.,Helmholtz Center Dresden | Hilger T.,TU Dresden | And 2 more authors.
Physical Review C - Nuclear Physics | Year: 2014

In view of the mass spectrum of heavy mesons in vacuum, the analytical properties of the solutions of the truncated Dyson-Schwinger equation for the quark propagator within the rainbow approximation are analyzed in some detail. In Euclidean space, the quark propagator is not an analytical function possessing, in general, an infinite number of singularities (poles) which hamper solving the Bethe-Salpeter equation. However, for light mesons (with masses Mqq̄1 GeV) all singularities are located outside the region within which the Bethe-Salpeter equation is defined. With an increase of the considered meson masses this region enlarges and already at masses 1 GeV, the poles of propagators of u, d, and s quarks fall within the integration domain of the Bethe-Salpeter equation. Nevertheless, it is established that for meson masses up to Mqq̄GeV only the first, mutually complex conjugated poles contribute to the solution. We argue that, by knowing the position of the poles and their residues, a reliable parametrization of the quark propagators can be found and used in numerical procedures of solving the Bethe-Salpeter equation. Our analysis is directly related to the future physics program at FAIR with respect to open charm degrees of freedom. © 2014 American Physical Society.


Kirillov A.A.,International University of Nature, Society and Man «Dubna» | Savelova E.P.,International University of Nature, Society and Man «Dubna»
International Journal of Modern Physics D | Year: 2016

We describe in details the procedure how the Lobachevsky space can be factorized to a space of the constant negative curvature filled with a gas of wormholes. We show that such wormholes have throat sections in the form of tori and are traversable and stable in the cosmological context. The relation of such wormholes to the dark matter phenomenon is briefly described. We also discuss the possibility of the existence of analogous factorizations for all types of homogeneous spaces. © 2016 World Scientific Publishing Company.


Savelova E.P.,International University of Nature, Society and Man «Dubna»
General Relativity and Gravitation | Year: 2016

We assume the spacetime foam picture in which vacuum is filled with virtual wormholes. In the presence of an external field the distribution of wormholes changes. We consider an anisotropic distribution of wormholes and analyze its relation to the speed of light. We show that speed of light acquires an anisotropic character and save the normal dispersion a gas of virtual wormholes may possess also an anomalous dispersion, i.e., when the light velocity exceeds that in the vacuum. © 2016, Springer Science+Business Media New York.


Gadjiev B.R.,International University of Nature, Society and Man «Dubna»
Journal of Physics: Conference Series | Year: 2010

In this paper we investigate peculiarities of phase transition high-symmetry -incommensurate phase in inhomogeneous systems. We have obtained the fractional differential equation for the order parameter and defined the space distribution of the order parameter in the incommensurate phase. We have obtained the nonlinear dispersion law and then present a renormalization group analysis of phase transitions in multiferroics. We have determined the dependence of critical indices on the nonextensivity parameter of the system. © 2010 IOP Publishing Ltd.


Shatunovskiy I.B.,International University of Nature, Society and Man «Dubna»
Komp'juternaja Lingvistika i Intellektual'nye Tehnologii | Year: 2014

Perlocutionary verbs like ubezhhdat' 'to convince / persuade', nastaivat' 'to insist', ugovarivat' ≈'to persuade', uspokaivat' 'to calm', objasn'at' 'to explain', xvastatsy'a 'to boast' etc. are verbs denoting perlocutionary actions. Perlocutionary actions, as defined in the paper, are unconventional actions performed by means of conventional illocutionary acts. Perlocutionary actions are aimed to achieve certain effects, goals, but they do not necessarily achieve them. Perlocutionary verbs such as preduprezhdat' (to warn), nastaivat' (to insist), uveryat' ('to assure') can turn into illocutionary verbs. In this case the perlocutionary text is contracted and some parts of it are taken in the meaning of the verb becoming a sign of that contraction. Perlocutionary actions and verbs can be divided into several groups according to supposed goals and effects of a perlocutionary action. They are: (1) perlocutionary actions having a clear aim which is embedded, fixed in the meaning of the verb denoting that action; this aim can be achieved or not; (2) perlocutionary actions that do not have a clear aim, but have a bundle of possible aims that are not fixed in the meanings of the corresponding perlocutionary verbs; (3) perlocutionary (and some illocutionary) actions that have a clear aim, and that aim is achieved any time the speaker does that action. These groups differ with respect to the meaning of their perfective forms. In the paper these differences are described and explanations for semantic peculiarities of the perfective forms are proposed.


Kirillov A.A.,International University of Nature, Society and Man «Dubna» | Savelova E.P.,International University of Nature, Society and Man «Dubna»
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2012

We consider scattering of a plane electromagnetic wave by a wormhole. It is found that the scattered wave is depolarized and has a specific interference picture depending on parameters of the wormhole and the distance to the observer. It is proposed that such features can be important in the direct search of wormholes. © 2012.


Savelova E.P.,International University of Nature, Society and Man «Dubna»
Gravitation and Cosmology | Year: 2013

We assume that some amount of dark energy appears due to vacuum polarization in external classical fields. In the early Universe, perturbations in this energy may form actual wormholes. We show that actual wormholes give a negligible contribution to the change in the vacuum energy density, while their contribution to the mean curvature is apt to form the observed dark energy phenomenon. Using the contribution of wormholes to dark matter and dark energy, we find estimates for the characteristic parameters of the gas of wormholes. © 2013 Pleiades Publishing, Ltd.


Kirillov A.A.,International University of Nature, Society and Man «Dubna» | Savelova E.P.,International University of Nature, Society and Man «Dubna»
Gravitation and Cosmology | Year: 2013

It is shown that due to vacuum polarization effects virtual wormholes form a finite (of Planckian order) value of the energy density of zero-point fluctuations. However, such a huge value is compensated by the contribution of virtual wormholes to the mean curvature, and the observed value of the cosmological constant should be close to zero. A non-vanishing value appears due to vacuum polarization in external classical fields. © 2013 Pleiades Publishing, Ltd.


Gadjiev B.R.,International University of Nature, Society and Man «Dubna»
Journal of Physics: Conference Series | Year: 2011

In this paper we investigate peculiarities of phase transition in inhomogeneous systems. We consider a case of 'cubic' systems with anisotropy invariants in which the distribution of defects generates a small-world property. We define a fractional equation of motion for the order parameter for the systems with a small world property. Linearization of the equation of motion for the order parameter made it possible to define a non-linear dispersion law. A renormalization group analysis of phase transitions in the generalized inhomogeneous "cubic" systems is presented. We discuss the dependence of critical behavior on the nonextensivity parameter of the system. © Published under licence by IOP Publishing Ltd.


Kirillov A.,International University of Nature, Society and Man «Dubna» | Savelova E.P.,International University of Nature, Society and Man «Dubna»
Monthly Notices of the Royal Astronomical Society | Year: 2011

The observed dark matter phenomenon is attributed to the presence of a gas of wormholes. We show that due to topological polarization effects, the background density of baryons generates non-vanishing values for wormhole rest masses. We infer basic formulae for the scattering cross-section between baryons and wormholes and equations of motion. Such equations are then used for the kinetic and hydrodynamic description of the gas of wormholes. In the Newtonian approximation, we consider the behaviour of density perturbations and show that at very large distances wormholes behave exactly like heavy non-baryonic particles, thus reproducing all features of cold dark matter models. At smaller galactic scales, wormholes strongly interact with baryons and cure the problem of cusps. We also show that collisions of wormholes and baryons lead to some additional damping of the Jeans instability in baryons. © 2011 The Authors Monthly Notices of the Royal Astronomical Society © 2011 RAS.

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