Astrophysical Objects
Recently Published Documents


TOTAL DOCUMENTS

163
(FIVE YEARS 58)

H-INDEX

17
(FIVE YEARS 4)

2021 ◽  
Vol 85 (4) ◽  
pp. 412-414
Author(s):  
V. S. Romanenko ◽  
V. B. Petkov ◽  
Yu. Z. Afashokov ◽  
E. A. Gorbacheva ◽  
D. D. Dzhappuev ◽  
...  

Data ◽  
2021 ◽  
Vol 6 (1) ◽  
pp. 4
Author(s):  
Evgeny Mikhailov ◽  
Daniela Boneva ◽  
Maria Pashentseva

A wide range of astrophysical objects, such as the Sun, galaxies, stars, planets, accretion discs etc., have large-scale magnetic fields. Their generation is often based on the dynamo mechanism, which is connected with joint action of the alpha-effect and differential rotation. They compete with the turbulent diffusion. If the dynamo is intensive enough, the magnetic field grows, else it decays. The magnetic field evolution is described by Steenbeck—Krause—Raedler equations, which are quite difficult to be solved. So, for different objects, specific two-dimensional models are used. As for thin discs (this shape corresponds to galaxies and accretion discs), usually, no-z approximation is used. Some of the partial derivatives are changed by the algebraic expressions, and the solenoidality condition is taken into account as well. The field generation is restricted by the equipartition value and saturates if the field becomes comparable with it. From the point of view of mathematical physics, they can be characterized as stable points of the equations. The field can come to these values monotonously or have oscillations. It depends on the type of the stability of these points, whether it is a node or focus. Here, we study the stability of such points and give examples for astrophysical applications.


Metafizika ◽  
2020 ◽  
pp. 82-93
Author(s):  
V. G Krechet

In this article, within the framework of general relativity, the possible effect of the gravitational interaction of Dirac nonlinear spinor fields on the evolution of the Universe, on the formation of astrophysical objects and on the formation of the geometry of the local space-time of elementary particles with spin ħ / 2 is considered.


Metafizika ◽  
2020 ◽  
pp. 166-174
Author(s):  
I. A Babenko

The article discusses the theoretical and experimental foundations of the hypothesis on the origin the magnetic field's the Earth's and other astrophysical objects, put forward at the beginning of the twentieth century by Sutherland and Einstein. According to this hypothesis, the different of the electric charg of the electron and proton and the rotation of the Earth (astronomical), leads to the appearance of a magnetic field. Experiments under terrestrial conditions aimed at determining the difference between the electric charges of an electron and a proton are discussed.


2020 ◽  
pp. 50-54
Author(s):  
I. Marushchenko ◽  
N.A. Azarenkov

In the paper, the Braginskii equations for relativistic electrons in hot plasmas with slow macroscopic fluxes are derived. This consideration is suitable for description of the typical fusion plasma with the temperatures of about several tens of kiloelectronvolt, when the plasma rotation and the longitudinal currents should be taken into account. Contrary to other papers devoted to classical description of transport processes in fusion devices, as well as to fully relativistic description of the astrophysical objects, we propose the mixed approach with fully relativistic kinetics for the hot electrons and non-relativistic macroscopic fluxes. The obtained form of the Braginskii equations includes all important features of relativistic hydrodynamics, has the same form as the classical representation, which is currently implemented into modern transport codes, and can easily replace the latter.


Author(s):  
Sergey L. Cherkas ◽  
Vladimir L. Kalashnikov

A spherically symmetric solution for a gravitational field is considered in the conformally-unimodular metric. The reason for the study of this particular gauge (i. e., conformally-unimodular metric) is its relation to the vacuum energy problem. That aim connects it to other physical phenomena (including black holes), and one could argue that they should be considered in this particular class of metrics. As the vacuum solutions, so the incompressible liquid ones are investigated. In the last case, the nonsingular «eicheon» appears as a non-point compact static object that possessed different masses and structures. Such objects are a final product of the stellar collapse, with the masses exceeding the Tolman – Oppenheimer – Volkoff limit. The term «eicheon» refers to the fundamental G. Weyl’s paper «Gravitation und Elektrizität», published, in particular in the book «Das Relativitätsprinzip. Eine Sammlung von Originalarbeiten zur Relativitätstheorie Einsteins» (Berlin, 2018), where he introduced the concept of gauge invariance (German Eichtheorie) firstly in its relation to the unified field theory. Using this term to describe the compact nonsingular astrophysical objects emphasizes the decisive role of the gauge fixing by the unimodular metric. Besides, the connotation with Eichel (acorn) stresses the twofold internal structure of an object: as a point-like in the unimodular metric and a surface in the Schwarzschild one. The radial geodesic lines are investigated in the conformally-unimodular metric, as well.


Sign in / Sign up

Export Citation Format

Share Document