arXiv subjects

Irina Dymnikova

Publications and source records attributed to Irina Dymnikova.

At least 19 recordsLinked to original sources

arXiv2015

Elementary Superconductivity in Nonlinear Electrodynamics Coupled to Gravity

Source-free equations of nonlinear electrodynamics minimally coupled to gravity admit regular axially symmetric asymptotically Kerr-Newman solutions which describe charged rotating black holes and electromagnetic spinning solitons (lumps). Asymptotic analysis of solutions shows, for both black holes and solitons, the existence of de Sitter vacuum interior which has the properties of a perfect conductor and ideal diamagnetic and displays superconducting behaviour which can be responsible for practically unlimited life time of an object. Superconducting current flows on the equatorial ring replacing the Kerr ring singularity of the Kerr-Newman geometry. Interior de Sitter vacuum supplies the electron with the finite positive electromagnetic mass related the interior de Sitter vacuum of the electroweak scale and to breaking of space-time symmetry, which allows to explain the mass-square differences for neutrino and the appearance of the minimal length scale in the annihilation reaction $e^{+}e^{-}\rightarrowγγ(γ)$.

gr-qc↗

arXiv2015

Regular rotating electrically charged black holes and solitons in nonlinear electrodynamics minimally coupled to gravity

In nonlinear electrodynamics coupled to gravity, regular spherically symmetric electrically charged solutions satisfy the weak energy condition and have obligatory de Sitter centre. By the Gürses-Gürsey algorithm they are transformed to spinning electrically charged solutions asymptotically Kerr-Newman for a distant observer. Rotation transforms de Sitter center into de Sitter vacuum surface which contains equatorial disk $r=0$ as a bridge. We present general analysis of the horizons, ergoregions and de Sitter surfaces, as well as the conditions of the existence of regular solutions to the field equations. We find asymptotic solutions and show that de Sitter vacuum surfaces have properties of a perfect conductor and ideal diamagnetic, violation of the weak energy condition is prevented by the basic requirement of electrodynamics of continued media, and the Kerr ring singularity is replaced with the superconducting current.

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arXiv2015

Regular black hole remnants and graviatoms with de Sitter interior as heavy dark matter candidates probing inhomogeneity of early universe

We address the question of regular primordial black holes with de Sitter interior, their remnants and gravitational vacuum solitons G-lumps as heavy dark matter candidates providing signatures for inhomogeneity of early universe, which is severely constrained by the condition that the contribution of these objects in the modern density does not exceed the total density of dark matter. Primordial black holes and their remnants seem to be most elusive among dark matter candidates. However, we reveal a nontrivial property of compact objects with de Sitter interior to induce proton decay or decay of neutrons in neutron stars. The point is that they can form graviatoms, binding electrically charged particles. Their observational signatures as dark matter candidates provide also signatures for inhomogeneity of the early universe. In graviatoms, the cross-section of the induced proton decay is strongly enhanced, what provides the possibility of their experimental searches. We predict proton decay paths induced by graviatoms in the matter as an observational signature for heavy dark matter searches at the IceCUBE experiment.

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arXiv2015

Electromagnetic source for the Kerr-Newman geometry

Source-free equations of nonlinear electrodynamics minimally coupled to gravity (NED-GR) admit regular axially symmetric asymptotically Kerr-Newman solutions, which describe electrically charged rotating black holes and spinning solitons. Asymptotic analysis of solutions shows the existence of de Sitter vacuum interior which has the properties of a perfect conductor and an ideal diamagnetic. The Kerr ring singularity (a naked singularity in the case without horizons) is replaced with a superconducting current, which serves as a nondissipative source of the Kerr-Newman fields and can be responsible for an unlimited life time of a spinning object.

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arXiv2012

Triple-horizon spherically symmetric spacetime and holographic principle

We present a family of spherically symmetric spacetimes, specified by the density profile of a vacuum dark energy, which have the same global structure as the de Sitter spacetime but the reduced symmetry which leads to a time-evolving and spatially inhomogeneous cosmological term. It connects smoothly two de Sitter vacua with different values of cosmological constant and corresponds to anisotropic vacuum dark fluid defined by symmetry of its stress-energy tensor which is invariant under the radial boosts. This family contains a special class distinguished by dynamics of evaporation of a cosmological horizon which evolves to the triple horizon with the finite entropy, zero temperature, zero curvature, infinite positive specific heat, and infinite scrambling time. Non-zero value of the cosmological constant in the triple-horizon spacetime is tightly fixed by quantum dynamics of evaporation of the cosmological horizon.

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arXiv2012

Multi-horizon spherically symmetric spacetimes with several scales of vacuum energy

We present a family of spherically symmetric multi-horizon spacetimes with a vacuum dark fluid, associated with a time-dependent and spatially inhomogeneous cosmological term. The vacuum dark fluid is defined in a model-independent way by the symmetry of its stress-energy tensor, i.e., its invariance under Lorentz boosts in a distinguished spatial direction ($p_r=-ρ$ for spherical symmetry), which makes the dark fluid essentially anisotropic and allows its density to evolve. The related cosmological models belong to the Lemaitre class of models with anisotropic fluids and describe a universe with several scales of vacuum energy related to phase transitions during its evolution. The typical behavior of solutions and the number of spacetime horizons are determined by the number of vacuum scales. We study in detail a model with three vacuum scales: GUT, QCD and that responsible for the present accelerated expansion. The model parameters are fixed by the observational data and by analyticity and causality conditions. We find that our Universe has three horizons. During the first inflation the Universe enters a T-region which makes the expansion irreversible. After the second phase transition at the QCD scale the Universe enters an R-region, where for a long time its geometry remains almost pseudo-Euclidean. After crossing the third horizon related to the present vacuum density, the Universe should enter the next T-region with inevitable expansion.

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arXiv2009

Minimal Length Scale in Annihilation

Experimental data suggest the existence of a minimal length scale in annihilation process for the reaction e+e- --> gamma gamma (gamma). Nonlinear electrodynamics coupled to gravity and satisfying the weak energy condition predicts, for an arbitrary gauge invariant lagrangian, the existence of a spinning charged electromagnetic soliton asymptotically Kerr-Newman for a distant observer with a gyromagnetic ratio g=2. Its internal structure includes an equatorial disk of de Sitter vacuum which has properties of a perfect conductor and ideal diamagnetic, and displays superconducting behavior within a single spinning soliton. De Sitter vacuum supplies a particle with the finite positive electromagnetic mass related to breaking of space-time symmetry. We apply this approach to interpret the existence of a minimal characteristic length scale in annihilation.

hep-ph↗

arXiv2006

Spinning superconducting electrovacuum soliton

In nonlinear electrodynamics coupled to general relativity and satisfying the weak energy condition, a spherically symmetric electrically charged electrovacuum soliton has obligatory de Sitter center in which the electric field vanishes while the energy density of electromagnetic vacuum achieves its maximal value. De Sitter vacuum supplies a particle with the finite positive electromagnetic mass related to breaking of space-time symmetry from the de Sitter group in the origin. By the Gürses-Gürsey algorithm based on the Newman-Trautman technique it is transformed into a spinning electrovacuum soliton asymptotically Kerr-Newman for a distant observer. De Sitter center becomes de Sitter equatorial disk which has both perfect conductor and ideal diamagnetic properties. The interior de Sitter vacuum disk displays superconducting behavior within a single spinning soliton. This behavior found for an arbitrary nonlinear lagrangian ${\cal L}(F)$, is generic for the class of regular spinning electrovacuum solutions describing both black holes and particle-like structures.

hep-th↗

arXiv2006

Gauge-noninvariance of quantum cosmology and vacuum dark energy

We address the question how to adapt cosmological constant $Λ$ for description of a vacuum dark energy density jumping from the big initial value to the small today value suggested by observations. We find such a possibility in the gauge-noninvariance of quantum cosmology which leads to a connection between a choice of the gauge and quantum spectrum for a certain physical quantity which can be specified in the framework of the minisuperspace model. We introduce a particular gauge in which the cosmological constant $Λ$ is quantized and show that making a measurement of $Λ$ today one can find its small value with the biggest probability, while at the beginning of the evolution, the biggest probability corresponds to its biggest value. Transitions between quantum levels of $Λ$ in the course of the Universe evolution, could be related to several scales for symmetry breaking.

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arXiv2004

Stability of a vacuum nonsingular black hole

This is the first of series of papers in which we investigate stability of the spherically symmetric space-time with de Sitter center. Geometry, asymptotically Schwarzschild for large $r$ and asymptotically de Sitter as $r\to 0$, describes a vacuum nonsingular black hole for $m\geq m_{cr}$ and particle-like self-gravitating structure for $m < m_{cr}$ where a critical value $m_{cr}$ depends on the scale of the symmetry restoration to de Sitter group in the origin. In this paper we address the question of stability of a vacuum non-singular black hole with de Sitter center to external perturbations. We specify first two types of geometries with and without changes of topology. Then we derive the general equations for an arbitrary density profile and show that in the whole range of the mass parameter $m$ objects described by geometries with de Sitter center remain stable under axial perturbations. In the case of the polar perturbations we find criteria of stability and study in detail the case of the density profile $ρ(r)=ρ_0 e^{-r^3/r_0^2 r_g}$ where $ρ_0$ is the density of de Sitter vacuum at the center, $r_0$ is de Sitter radius and $r_g$ is the Schwarzschild radius.

gr-qc↗

arXiv2004

Regular electrically charged structures in Nonlinear Electrodynamics coupled to General Relativity

We address the question of existence of regular spherically symmetric electrically charged solutions in Nonlinear Electrodynamics coupled to General Relativity. Stress-energy tensor of the electromagnetic field has the algebraic structure $T_0^0=T_1^1$. In this case the Weak Energy Condition leads to the de Sitter asymptotic at approaching a regular center. In de Sitter center of an electrically charged NED structure, electric field, geometry and stress-energy tensor are regular without Maxwell limit which is replaced by de Sitter limit: energy density of a field is maximal and gives an effective cut-off on self-energy density, produced by NED coupled to gravity and related to cosmological constant $Λ$. Regular electric solutions satisfying WEC, suffer from one cusp in the Lagrangian ${\cal L}(F)$, which creates the problem in an effective geometry whose geodesics are world lines of NED photons. We investigate propagation of photons and show that their world lines never terminate which suggests absence of singularities in the effective geometry. To illustrate these results we present the new exact analytic spherically symmetric electric solution with the de Sitter center.

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arXiv2003

Cosmological term, mass, and space-time symmetry

In the spherically symmetric case the requirements of regularity of density and pressures and finiteness of the ADM mass $m$, together with the weak energy condition, define the family of asymptotically flat globally regular solutions to the Einstein minimally coupled equations which includes the class of metrics asymptotically de Sitter as $r\to 0$. A source term connects smoothly de Sitter vacuum in the origin with the Minkowski vacuum at infinity and corresponds to anisotropic vacuum defined macroscopically by the algebraic structure of its stress-energy tensor invariant under boosts in the radial direction. Dependently on parameters, geometry describes vacuum nonsingular black holes, and self-gravitating particle-like structures whose ADM mass is related to both de Sitter vacuum trapped in the origin and smooth breaking of space-time symmetry. The geometry with the regular de Sitter center has been applied to estimate geometrical limits on sizes of fundamental particles, and to evaluate the gravito-electroweak unification scale from the measured mass-squared differences for neutrino.

hep-th↗

arXiv2003

A theoretical case for negative mass-square for sub-eV particles

Electroweak gauge bosons have masses of the order of 10^2 GeV, while masses of additional bosons involved in gravito-electroweak unification are expected to be still higher. These are at least eleven orders of magnitude higher than sub-eV range indications for neutrino masses. Under these circumstances we suspect that the sub-eV particles are created in a spacetime where gravitational effects of massive gauge bosons may become important. The question that we thus ask is: What is the spacetime group around a gravito-electroweak vertex? Modeling it as de-Sitter we find that sub-eV particles may carry a negative mass square of the order of - (3/8 π^3) (M_unif./M_Planck)^4 M_Planck^2. Neutrino oscillation data then hints at 30-75 TeV scale for M_unif., where M_unif. characterizes gravito-electroweak unification scale.

hep-ph↗

arXiv2003

$Λ^{mu}_ν$ geometries from the point of view of different observers

$Λ^μ_ν$-geometry is a geometry with a variable cosmological term described by a second-rank symmetric tensor $Λ^μ_ν$ whose asymptotics are Einstein cosmological term $Λδ^μ_ν$ at the origin and $λδ^μ_ν$ at infinity (with $λ< Λ$). It corresponds to extension of the algebraic structure of the Einstein cosmological term $Λδ^μ_ν$ in such a way that a scalar $Λ$ describing vacuum energy density as $ρ_{vac}=8πG Λ$ (with $ρ_{vac}$=const by virtue of the Bianchi identities), becomes explicite related to the appropriate component, $Λ^0_0$, of an appropriate stress-energy tensor, $T^μ_ν=8πGΛ^μ_ν$ whose vacuum properties follow from its symmetry, $T_0^0=T_1^1$, and whose variability follows from the contracted Bianchi identities. In the spherically symmetric case existence of such geometries in frame of GR follows from imposing on Einstein equations requirements of finiteness of the ADM mass $m$, and of regularity of density and pressures. Dependently on parameters $m$ and $q=\sqrt{Λ/λ}$, $Λ^μ_ν$ geometry describes five types of configurations. We summarize here the results which tell us how these configurations look from the point of view of different observers: a static observer, a Lemaitre co-moving observer, and a Kantowski-Sachs observer.

gr-qc↗

arXiv2003

Spherically symmetric space-time with the regular de Sitter center

The requirements are formulated which lead to the existence of the class of globally regular solutions to the minimally coupled GR equations which are asymptotically de Sitter at the center. The brief review of the resulting geometry is presented. The source term, invariant under radial boots, is classified as spherically symmetric vacuum with variable density and pressure, associated with an r-dependent cosmological term, whose asymptotic in the origin, dictated by the weak energy condition, is the Einstein cosmological term. For this class of metrics the ADM mass is related to both de Sitter vacuum trapped in the origin and to breaking of space-time symmetry. In the case of the flat asymptotic, space-time symmetry changes smoothly from the de Sitter group at the center to the Lorentz group at infinity. Dependently on mass, de Sitter-Schwarzschild geometry describes a vacuum nonsingular black hole, or G-lump - a vacuum selfgravitating particlelike structure without horizons. In the case of de Sitter asymptotic at infinity, geometry is asymptotically de Sitter at both origin and infinity and describes, dependently on parameters and choice of coordinates, a vacuum nonsingular cosmological black hole, selfgravitating particlelike structure at the de Sitter background and regular cosmological models with smoothly evolving vacuum energy density.

gr-qc↗

arXiv2003

Putting non Point-like Behavior of Fundamental Particles to Test

We review the experimental limits on those hypothetical interactions where the fundamental particles could exhibit non point-like behavior. In particular we have focused on the QED reaction measuring the differential cross sections for the process $ \EEGG $ at energies around 91 GeV and 209 GeV with data collected from the L3 detector from 1991 to 2001. With a global fit L3 set lower limits at $ 95 % $ CL on a contact interaction energy scale parameter $Λ> 1.6 $ TeV, which restricts the characteristic QED size of the interaction region to $ R_{e} < 1.2 \times 10^{-17} $ cm. All the interaction regions are found to be smaller than the Compton wavelength of the fundamental particles. This constraint we use to estimate a lower limit on the internal density of particle-like structure with the de Sitter vacuum core. Some applications of obtained limits to the string and quantum gravity scales are also discussed.

hep-ph↗

arXiv2002

Limits on Sizes of Fundamental Particles and on Gravitational Mass of a Scalar

We review the experimental limits on mass of excited fundamental particles and contact interaction energy scale parameters $Λ$ for QCD, QED and electroweak reactions. In particular we have focused on the QED reaction $ \EEGG $ at the energies from 91GeV{} to 202GeV{} using the differential cross-sections measured by the L3 Collaboration from 1991 to 1999. A global fit leads to lower limits at $ 95 % $ CL on $Λ> 1687$ GeV, which restricts the characteristic QED size of the interaction region to $ R_{e} < 1.17 \times 10^{-17} $ cm. All the interaction regions are found to be smaller than the Compton wavelength of the fundamental particles. This constraint is used to estimate a lower limit on the size of a fundamental particle related to gravitational interaction, applying the model of self-gravitating particle-like structure with the de Sitter vacuum core. It gives $r_τ \geq 2.3 \times {10^{-17}}$ cm and $r_{e} \geq 1.5 \times 10^{-18} $ cm, if leptons get masses at the electroweak scale, and $r_τ \geq 3.3 \times {10^{-27}}$ cm, $r_{e} \geq 4.9 \times 10^{-26} $ cm, as the most stringent limits required by causality arguments. This sets also an upper limit on the gravitational mass of a scalar $m_{scalar} \leq{154} $ GeV{} at the electroweak scale and (m_{scalar} \leq \sqrt{3/8} m_{Pl}) as the most stringent limit.

hep-ph↗

arXiv2002

From vacuum nonsingular black hole to variable cosmological constant

We outline the class of globally regular spherically symmetric solutions to the minimally coupled GR equations asymptotically de Sitter in the origin and asymptotically Schwarzschild at infinity. A source term connects smoothly de Sitter vacuum at the regular center with Minkowski vacuum at infinity and corresponds to anisotropic spherically symmetric vacuum defined macroscopically by the algebraic structure of its stress-energy tensor invariant under boosts in the radial direction. De Sitter-Schwarzschild geometry describes a vacuum nonsingular black hole which evolves, in the course of Hawking evaporation, towards a self-gravitating particle-like structure without horizons, G-lump. Space-time symmetry changes smoothly from the de Sitter group in the center to the Lorentz group at infinity, and the standard formula for the ADM mass relates it to the de Sitter vacuum replacing a singularity at the scale of symmetry restoration. This class of metrics is easily extended to the case of a nonzero background cosmological constant. A source term connects then smoothly two de Sitter vacua with different values of cosmological constant which makes possible to associate anisotropic spherically symmetric vacuum with an r-dependent cosmological term.

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