arXiv subjects

E. P. Savelova

Publications and source records attributed to E. P. Savelova.

At least 19 recordsLinked to original sources

arXiv2024

Application of Machine Learning Methods for Detecting Atypical Structures in Astronomical Maps

The paper explores the use of various machine learning methods to search for heterogeneous or atypical structures on astronomical maps. The study was conducted on the maps of the cosmic microwave background radiation from the Planck mission obtained at various frequencies. The algorithm used found a number of atypical anomalous structures in the actual maps of the Planck mission. This paper details the machine learning model used and the algorithm for detecting anomalous structures. A map of the position of such objects has been compiled. The results were compared with known astrophysical processes or objects. Future research involves expanding the dataset and applying various algorithms to improve the detection and classification of outliers.

astro-ph.IM↗

arXiv2024

Possible scenario of relic wormhole formation

It is shown that in the presence of virtual wormholes, the vacuum is unstable, which leads to a series of phase transitions in the early Universe. Then the standard Kibble scenario predicts the formation of defects such as domain walls. An unusual feature of virtual wormholes is that they generate defects with negative energy density. Such defects have macroscopic dimensions and can support the necks of already real primary wormholes, which gives reason to consider relic wormholes as realistic astrophysical objects.

gr-qc↗

arXiv2024

On properties of the distribution of virtual wormholes in a vacuum

A model of space-time foam in the form of an arbitrary distribution of spherical Euclidean wormholes is considered. A method for constructing the exact solution of Einstein's Euclidean equations for the metric corresponding to this model is proposed. In the framework of our model we obtain the expression for the Euclidean action and its dependence on the parameters of wormholes in the explicit form. It is shown how the solutions obtained make it possible to determine all possible correlation functions associated with the parameters of virtual wormholes in the vacuum state.

gr-qc↗

arXiv2020

Scattering of GWs on wormholes: foreshadow and afterglow/echoes from binary merges

We study specific features of the scattering of gravitational waves on wormholes and normal matter objects. We derive and solve the GW energy transport equation and show that the scattered signal lies in the same frequency spectrum bands as the basic signal. The scattering forms specific long living tails which always accompany the basic signal and have a universal form. The scattering on normal matter objects forms tails which have always the retarding character, while wormholes lead to advanced tails as well. In addition, wormholes may produce considerably stronger effect, when the total energy in tails exceeds the energy of the incident wave by the factor up to $10^{3}$ . In both cases the retarding tails have a long living character when the mean amplitude behaves with time as $h\sim 1/\sqrt{t+R/c}$. For a single GW event the echo tails give only a tiny contribution to the mean amplitude. However such tails accumulate with events and may be observed by their contribution to the noise produced by the stochastic GW background.

gr-qc↗

arXiv2020

Possible formation of ring galaxies by torus-shaped magnetic wormholes

We present the hypothesis that some of ring galaxies were formed by relic magnetic torus - shaped wormholes. In the primordial plasma before the recombination magnetic fields of wormholes trap baryons whose energy is smaller than a threshold energy. They work as the Maxwell's demons collecting baryons from the nearest (horizon size) region and thus forming clumps of baryonic matter which have the same torus-like shapes as wormhole throats. Such clumps may serve as seeds for the formation of ring galaxies and smaller objects having the ring form. Upon the recombination torus-like clumps may decay and merge. Unlike galaxies, such objects may contain less or even no dark matter in halos. However the most stringent feature of such objects is the presence of a large - scale toroidal magnetic field. We show that there are threshold values of magnetic fields which give the upper and lower boundary values for the baryon clumps in such protogalaxies.

gr-qc↗

arXiv2018

On distortion of the background radiation spectrum by wormholes: kinematic Sunyaev-Zel'dovich effect

The problem of scattering of the background radiation on relic cosmological wormholes is considered. It is shown that static wormholes do not perturb the spectrum at all. The presence of peculiar velocities of wormholes results in a distortion of the CMB spectrum which is analogous to the kinematic Sunyaev-Zel'dovich effect. In the first order in $v/c$ the distortion of CMB cannot be separated from from the Compton scattering on electrons. In next orders the scattering on wormholes exhibits some difference from the Compton scattering. High-energy cosmic-ray particles spectrum does not change the form by KSZ, but undergoes a common Doppler shift. Such features may give a new tool to detect the presence of relic wormholes in our Universe.

gr-qc↗

arXiv2015

On scattering of CMB radiation on wormholes: kinetic SZ-effect

The problem of scattering of CMB radiation on wormholes is considered. It is shown that a static gas of wormholes does not perturb the spectrum of CMB. In the first order by $v/c$ the presence of peculiar velocities gives rise to the dipole contribution in $ΔT/T$, which corresponds to the well-known kinetic Sunyaev-Zel'dovich effect. In next orders there appears a more complicated dependence of the perturbed CMB spectrum on peculiar velocities. We also discuss some peculiar features of the scattering on a single wormhole.

gr-qc↗

arXiv2015

Cosmological wormholes

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.

gr-qc↗

arXiv2015

Effective action for a free scalar field in the presence of spacetime foam

We model spacetime foam by a gas of virtual wormholes. For a free scalar field we derive the effective Lagrangian which accounts for the interaction with spacetime foam and contains two additional non-local terms. One term describes the scattering of scalar particles on virtual wormholes and explicitly reproduces the Pauli-Villars regularization procedure. The second term describes the back reaction of particles on the number density of wormholes and introduces a self-interaction between particles.

gr-qc↗

arXiv2015

Origin of the logarithmic correction to the Newton's law in the presence of a homogeneous gas of wormholes

We suggest a new scenario in which the Universe starts its evolution with a fractal topological structure. This structure is described by a gas of wormholes. It is shown that the polarization of such a gas in external fields possesses a spatial dispersion, which results in a modification of the Newton's law. The dependence on scales is determined by the distribution of distances between throat ends. The observed in galaxies logarithmic correction confirms that the distribution has fractal properties. We also discus the possibility of restoring such a distribution from observations.

gr-qc↗

arXiv2014

On the possibility of the generation of an artificial wormhole

We model spacetime foam by a gas of virtual wormholes. Then applying an external field one may change the density of virtual wormholes and try to organize a wormhole-like structure in space. The relation between an additional distribution of virtual wormholes and the external field is considered for the homogeneous case. We show that the external fields suppress the density of virtual wormholes which sets an obstruction for creating an actual wormhole in a straightforward fashion. We also present a rough idea of a more complicated model for the artificial creation of a wormhole.

gr-qc↗

arXiv2014

On possible origin of an anisotropy in the speed of light in vacuum

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.

gr-qc↗

arXiv2013

Dark energy from the gas of wormholes

We assume the space-time foam picture in which the vacuum is filled with a gas of virtual wormholes. It is shown that virtual wormholes form a finite (of the 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 is close to zero. A non-vanishing value appears due to the polarization of vacuum in external classical fields. In the early Universe some virtual wormholes may form actual ones. We show that in the case of actual wormholes vacuum polarization effects are negligible 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 characteristic parameters of the gas of wormholes.

astro-ph.CO↗

arXiv2012

Gas of wormholes in Euclidean quantum field theory

We model the spacetime foam picture by a gas of wormholes in Euclidean field theory. It is shown that at large distances the presence of such a gas leads merely to a renormalization of mass and charge values. We also demonstrate that there exist a class of specific distributions of point-like wormholes which essentially change the ultraviolet behavior of Green functions and lead to finite quantum field theories.

hep-th↗

arXiv2012

Artificial Wormhole

It is shown that recently reported result by the OPERA Collaboration (arXive:1109.4897) of an early arrival time of muon neutrinos with respect to the speed of light in vacuum does not violate standard physical laws. We show that vacuum polarization effects in intensive external fields may form a wormhole-like object. The simplest theory of such an effect is presented and basic principles of formation of an artificial wormhole are also considered.

astro-ph.CO↗

arXiv2011

On Scattering of Electromagnetic Waves by a Wormhole

We consider scattering of a plane electromagnetic wave by a wormhole. It is found that the scattered wave is partially 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.

astro-ph.CO↗

arXiv2010

Density perturbations in the gas of wormholes

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 formulas for the scattering 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 behavior of density perturbations and show that at very large distances wormholes behave exactly like heavy non-baryon particles, thus reproducing all features of CDM models. At smaller scales (at galaxies) 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.

astro-ph.CO↗

arXiv2009

On topological bias of discrete sources in the gas of wormholes

The model of space in the form of a static gas of wormholes is considered. It is shown that the scattering on such a gas gives rise to the formation of a specific diffuse halo around every discrete source. Properties of the halo are determined by the distribution of wormholes in space and the halo has to be correlated with the distribution of dark matter. This allows to explain the absence of dark matter in intergalactic gas clouds. Numerical estimates for parameters of the gas of wormholes are also obtained.

astro-ph.CO↗