Recent Contributions to Physics

ISSN

1563-0315

2663-2276

Издатель

Al-Farabi Kazakh National University

Ключевые слова

Galaxies: Formation, ...

Nuclear physics resea...

Stellar, planetary, a...

Particle physics theo...

Plasma Diagnostics an...

Публикации в журнале

Показано: 1 - 5 из 5

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Application of GBT theorem for Gravitational deflection of light by Compact Objects
(Al-Farabi Kazakh National University, 2023-03-13)
Nurzada Beissen
;
Daniya Utepova
;
Aray Muratkhan
;
Ayazhan Orazymbet
;
Manas Khassanov
One of the most renowned classical experiments that verifies the curved nature of space-time geometry is the bending of light. This phenomenon is extensively discussed in most textbooks on general relativity, with a clear and comprehensive explanation provided. In this study, we employ the material medium approach to determine the refractive index associated with the gravitational field of a compact object with a quadrupole moment. Our research presents a method for calculating the gravitational deflection angle for compact objects by utilizing the refractive index and the GBT theorem for an isotropic metric. This method is particularly important because it allows for the calculation of the deflection angle for both light and relativistic particles. The material medium approach enables us to consider the compact object's gravitational field as a medium with a refractive index. By applying this approach, we establish a relationship between the refractive index and the quadrupole moment of the compact object. We then utilize this relationship to calculate the deflection angle of light and relativistic particles.
Цитирования (OpenAlex) 6Цитирования (OpenCitations) 3
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Қоршаған әлем бейнесінің танымдық келбеті мен қайшылықтары туралы
(Al-Farabi Kazakh National University, 2020-06-25)
G.M. Autova
;
Viktor Kazachenok
;
Kanat Mukashevich Mukashev
Without science in modern society, its intellectual and industrial power, the security of the state, is impossible. Science has become an important criterion for the civilization and culture of nations. Scientific and technical development is the main trend of historical progress at the turn of the XX-XXI centuries. But the attitude towards science is twofold. The first direction expresses confidence in science. It is recognized as one of the main values of society and the dominant factor in the development of mankind. Proponents of the second direction criticize science for mistakes, see it as the main cause of crisis, environmental and social global problems. They believe that science is limited in its ability to solve the main and acute problems of social development. The roots of both directions have an objective basis. Therefore, today science is perceived in society ambiguously: on the one hand, with trust, hope and optimism, and on the other, with distrust and pessimism. But it is obvious that science cannot do without society in the 21st century. In light of this, the problems discussed and raised within the framework of this work did not arise from scratch and reflect the own views of its authors.
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The Influence of Deformation in Compact Objects on Redshift and Radar Echo Delay
(Al-Farabi Kazakh National University, 2024-03-19)
Nurzada Beissen
;
D.S. Utepova
;
V.N. Kossov
;
S. Toktarbay
;
M.K. Khassanov
The analogy between optics and mechanics provides a unified way to describe particle motion in mechanics and light propagation in geometrical optics, and recent publications have demonstrated that this analogy can also be applied to general relativity, specifically when dealing with static metrics. In this paper, we use the material medium approach to obtain the refractive index associated with the gravitational field of a compact object having a quadrupole moment. Within this approach, we explore well-known effects of general relativity such as redshift and radar echo delay, deriving mathematical expressions for these phenomena taking into account the influence of the quadrupole moment.
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N64 ШАҢ КӨПІРШІГІ АЙМАҒЫНДАҒЫ ЖАС ЖҰЛДЫЗДЫ ОБЪЕКТІЛЕР
(Al-Farabi Kazakh National University, 2026-09-07)
A.B. Manapbayeva
;
N.Sh. Alimgazinova
;
Aisha Zh. Naurzbayeva
;
А.Ж. Омар
;
Toktarkhan Komesh
The study of young stellar objects is one of the priority areas of modern astrophysics, since such objects allow us to directly study the physical processes that accompany the formation of stars and planetary systems. The goal of this study is to study the N64 dust bubble region and classify young stellar objects. Searching for young stellar objects using infrared data from astronomical catalogs is one of the most effective methods for studying the processes of star formation. Young stars and their associated structures are usually located in dense gas and dust clouds, which significantly hinders their observation at optical wavelengths. Unlike visible light, infrared radiation penetrates environments, allowing the detection and analysis of objects that are inaccessible to optical observations. In this study the detection of young stellar objects was performed using the method proposed by Gutermuth et al. (2008). The study used archival infrared data from Spitzer Space Telescope (IRAC: 3.6–8.0 μm; MIPS: 24 μm) and data from 2MASS catalog (J, H, ). For identified young stellar objects, color-color diagrams were created showing their location relative to characteristic regions corresponding to different evolutionary stages. In addition, spectral indices were calculated and spectral energy distributions were constructed to support the classification and evolutionary status of the detected objects. Analysis of the spatial distribution of young stellar objects in the early stages of evolution in N64 dust bubble revealed a clear concentration of sources along filamentary structures, indicating a connection between their formation and morphology of the dust cloud.
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Хорава-Лифшицтің f(R) гравитациясындағы тұтқыр сұйықтықтың эволюциясы
(Al-Farabi Kazakh National University, 2021-06-23)
Shynaray Myrzakul
;
M.Zh Esentai
;
G.A. Sotanova
;
Tolkynay Myrzakul
There are two modification methods that describe the accelerated expansion of the Universe: it is necessary either to modify the geometry or matter. Until now, many modified models have been proposed, one of which is common f(R) gravity. In f(R) gravity, in the well-known Einstein-Hilbert action, we replace the curvature tensor with its generalized function f(R), and the geometry changes. The unification of general relativity and quantum physics has become one of the most important issues of our time. In 1942, Lifshitz proposed a model based on high-energy anisotropic scaling that combines gravity and quantum physics, and in 2009 the Japanese scientist Peter Khorava proposed its unitary, renormalized version of gravity. In the studies of recent years, the name has spread - the gravity of Horava-Lifshits. In 2010, Masud Chaichyan, Shinichi Nojiri, Sergei D. Odintsov, Markku Oksanen, and Anka Tureanu jointly proposed a generalized form of this theory - f(R) gravity. In this work, the generalized gravity of Horava-Lifshitz will be studied for an inhomogeneous viscous fluid in space-time, based on this kind of gravity. At constant viscosity, with increasing time, the density and pressure of light and baryonic matter decrease. If we consider the state of dark energy, that is, the case when , then the density and pressure tend to infinity. Therefore, if we consider the viscosity constant, for the case in a vacuum, the universe will expand infinitely.

Recent Contributions to Physics

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