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Periodic Orbits in the Photogravitational Elliptic Restricted Three-Body Problem 光引力椭圆型受限三体问题中的周期轨道
Advances in Astrophysics Pub Date : 2018-08-01 DOI: 10.22606/adap.2018.33004
Y. S. Ruth, R. Sharma
{"title":"Periodic Orbits in the Photogravitational Elliptic Restricted Three-Body Problem","authors":"Y. S. Ruth, R. Sharma","doi":"10.22606/adap.2018.33004","DOIUrl":"https://doi.org/10.22606/adap.2018.33004","url":null,"abstract":"Periodic orbits in the elliptic restricted three-body problem are studied by considering the photogravitational and oblateness effects of the larger and smaller primary, respectively. The mean motion is derived with the help of averaging the distance r between the primaries over a revolution in terms of the mean anomaly. Collinear points L1, L2, L3 are studied for some of the Sun and its planet systems. The value of the critical mass μc is found, which decreases with the increase in radiation pressure and oblateness. The stability of the triangular points is studied using the analytical technique of Bennett. This is based on Floquet's theory for determination of characteristic exponents for periodic coefficients. Transition curves bounding the regions of stability in the μ-e plane, accurate to O(e2) are generated. Tadpole orbits, a combination of long-short periodic orbits, are produced for Sun-Jupiter and Sun-Saturn systems.","PeriodicalId":131060,"journal":{"name":"Advances in Astrophysics","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116226862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
The Electromagnetic Energy-Momentum Tensor in Expanding Universes 膨胀宇宙中的电磁能量-动量张量
Advances in Astrophysics Pub Date : 2018-08-01 DOI: 10.22606/ADAP.2018.33007
H. Fahr, M. Heyl
{"title":"The Electromagnetic Energy-Momentum Tensor in Expanding Universes","authors":"H. Fahr, M. Heyl","doi":"10.22606/ADAP.2018.33007","DOIUrl":"https://doi.org/10.22606/ADAP.2018.33007","url":null,"abstract":"In two previous papers the authors have investigated the characteristics of freely propagating cosmic photons in expanding homogenous flat universes from particle and wave points of view, respectively. The result was that the energy density of these freely propagating photons scales with 1/S3 instead with the generally accepted and redshift-related 1/S4, with S being the cosmic scale factor. This is a surprising result at first glance but finally very understandable if energy conservation has to be required also for cosmic photons without creating a conflict with observations. In this paper we treat freely propagating cosmic photons with a totally different approach, namely with the electromagnetic energy-momentum tensor (from now on abbreviated with EMT). The implementation of the EMT, when correctly interpreted for freely propagating photons, into Einstein’s field equations then automatically leads to the same 1/S3-scaling law for the energy density of cosmic photons, herewith confirming the results found earlier for the particle and wave view. We conclude that the observed cosmological redshift of photons (energy density ∝ 1/S4) is compatible with the law of energy conservation, i.e energy density ∝ 1/S3 if interpreted on a new physical basis.","PeriodicalId":131060,"journal":{"name":"Advances in Astrophysics","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133867947","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Application of the Non-Local Physics in the Theory of the Matter Movement in Black Holes 非局域物理在黑洞物质运动理论中的应用
Advances in Astrophysics Pub Date : 2018-08-01 DOI: 10.22606/adap.2018.33001
B. Alexeev
{"title":"Application of the Non-Local Physics in the Theory of the Matter Movement in Black Holes","authors":"B. Alexeev","doi":"10.22606/adap.2018.33001","DOIUrl":"https://doi.org/10.22606/adap.2018.33001","url":null,"abstract":"The theory of the matter movement in black holes (BH) in the frame of non – local quantum hydrodynamics (NLQHD) is considered. The theory corresponds to the limit case when the matter density tends to infinity when the theory of General Relativity is not applicable in principle. From calculations follow that NLQHD equations for the black holes have the solutions limited in space. The domain of the solution existence is limited by the event horizon where gravity tends to infinity. It was shown: 1) internal perturbations in BH lead to the appearance of the packets of the gravitational waves. 2) The width of the wave packet is inversely proportional to the magnitude of internal energy. 3) Increasing of the internal energy leads to the transformation of the mode of antigravity into the attraction regime. 4) A strong mutual influence of the gravitational, antigravitational and electromagnetic fields exists. The velocity of gravitational waves is more than the speed of light. The numerical calculations of the Cauchy problem are delivered.","PeriodicalId":131060,"journal":{"name":"Advances in Astrophysics","volume":"221 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132108395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Low-energy Quantum Gravity and Cosmology without Dark Energy 没有暗能量的低能量子引力和宇宙学
Advances in Astrophysics Pub Date : 2018-05-01 DOI: 10.22606/ADAP.2019.41001
Michael A. Ivanov
{"title":"Low-energy Quantum Gravity and Cosmology without Dark Energy","authors":"Michael A. Ivanov","doi":"10.22606/ADAP.2019.41001","DOIUrl":"https://doi.org/10.22606/ADAP.2019.41001","url":null,"abstract":"The model of low-energy quantum gravity leads to small additional effects having essential cosmological consequences: redshifts of remote objects and the additional dimming of them may be interpreted without any expansion of the Universe and without dark energy. The theoretical luminosity distance of the model fits the observational Hubble diagrams with high confidence levels. In the model, the ratio H(z)/(1+z) should be equal to the Hubble constant. The constancy of this ratio is confirmed with high probabilities by fitting the compilation of H(z) observations. A deceleration of massive bodies due to forehead and backhead collisions with gravitons is re-computed here.","PeriodicalId":131060,"journal":{"name":"Advances in Astrophysics","volume":"103 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125050719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 6
Self-gravitating Envelope Solitons in a Degenerate Quantum Plasma System 简并量子等离子体系统中的自引力包络孤子
Advances in Astrophysics Pub Date : 2018-03-04 DOI: 10.22606/adap.2018.34005
N. Ahmed, N. A. Chowdhury, A. Mannan, A. Mamun
{"title":"Self-gravitating Envelope Solitons in a Degenerate Quantum Plasma System","authors":"N. Ahmed, N. A. Chowdhury, A. Mannan, A. Mamun","doi":"10.22606/adap.2018.34005","DOIUrl":"https://doi.org/10.22606/adap.2018.34005","url":null,"abstract":"The existence and the basic features of ion-acoustic (IA) envelope solitons in a self-gravitating degenerate quantum plasma system (SG-DQPS), containing inertial non-relativistically degenerate light and heavy ion species as well as inertialess non-relativistically degenerate positron and electron species, have been theoretically investigated by deriving the nonlinear Schr\"{o}dinger (NLS) equation. The NLS equation, which governs the dynamics of the IA waves, has disclosed the modulationally stable and unstable regions for the IA waves. The unstable region allows to generate bright envelope solitons which are modulationaly stable. It is found that the stability and the growth rate dependent on the plasma parameters (like, mass and number density of the plasma species). The implications of our results in astronomical compact object (viz. white dwarfs, neutron stars, and black holes, etc.) are briefly discussed.","PeriodicalId":131060,"journal":{"name":"Advances in Astrophysics","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127882403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
Calculation of Apsidal Precession via Perturbation Theory 用摄动理论计算副旋进
Advances in Astrophysics Pub Date : 2018-02-20 DOI: 10.22606/adap.2019.43003
L. Barbieri, F. Talamucci
{"title":"Calculation of Apsidal Precession via Perturbation Theory","authors":"L. Barbieri, F. Talamucci","doi":"10.22606/adap.2019.43003","DOIUrl":"https://doi.org/10.22606/adap.2019.43003","url":null,"abstract":"The calculus of apsidal precession frequencies of the planets is developed by means of a perturbation thecnique. A model of concentric rings (ring model), suitable for improving calculations, is introduced. Conclusive remarks concerning a comparison between the theoretical, the calculated and the observed data of the precession frequencies are performed.","PeriodicalId":131060,"journal":{"name":"Advances in Astrophysics","volume":"167 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116914078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
The Spinning Equations of Motion for Objects in AP-Geometry ap -几何中物体的旋转运动方程
Advances in Astrophysics Pub Date : 2018-02-12 DOI: 10.22606/adap.2018.33002
M. Kahil
{"title":"The Spinning Equations of Motion for Objects in AP-Geometry","authors":"M. Kahil","doi":"10.22606/adap.2018.33002","DOIUrl":"https://doi.org/10.22606/adap.2018.33002","url":null,"abstract":"Equations of spinning objects are obtained in Absolute Parallelism Geometry [AP], a special class of non-Riemannian geometry admitting an alternative non-vanishing curvature and torsion simultaneously. This new set of equations is the counterpart of the Papapetrou equations in the Riemannian geometry. Applying, the concept of geometerization of physics, it may give rise to describe the spin tensor as parameterized commutation relation between path and path deviation equations in both Riemannian and non-Riemannian geometries.","PeriodicalId":131060,"journal":{"name":"Advances in Astrophysics","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122643546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 6
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