arXiv: General Relativity and Quantum Cosmology最新文献_第8页

Shadows of accelerating black holes 加速黑洞的阴影

arXiv: General Relativity and Quantum Cosmology Pub Date : 2020-10-23 DOI: 10.1103/PHYSREVD.103.025005

Ming Zhang, Jie Jiang

引用次数: 28

Quasi-local mass and isometric embedding with reference to a static spacetime 参考静态时空的准局部质量和等距嵌入

arXiv: General Relativity and Quantum Cosmology Pub Date : 2020-10-23 DOI: 10.2969/aspm/08510453

Mu-Tao Wang

引用次数: 1

Strong gravitational lensing in a spacetime with topological charge within the Eddington-inspired Born-Infeld gravity 在爱丁顿启发的玻恩-因菲尔德引力中具有拓扑电荷的时空中的强引力透镜

arXiv: General Relativity and Quantum Cosmology Pub Date : 2020-10-22 DOI: 10.1103/PHYSREVD.103.044047

C. Furtado, J. Nascimento, A. Petrov, P. Porf'irio, A. R. Soares

引用次数: 5

1+3 formulation of Newton’s equations 牛顿方程的1+3形式

arXiv: General Relativity and Quantum Cosmology Pub Date : 2020-10-20 DOI: 10.1103/physrevd.102.124005

Quentin Vigneron

{"title":"1+3\u0000 formulation of Newton’s equations","authors":"Quentin Vigneron","doi":"10.1103/physrevd.102.124005","DOIUrl":"https://doi.org/10.1103/physrevd.102.124005","url":null,"abstract":"We present in this paper a 4-dimensional formulation of the Newton equations for gravitation on a Lorentzian manifold, inspired from the 1+3 and 3+1 formalisms of general relativity. We first show that the freedom on the coordinate velocity of a general time-parametrised coordinate system with respect to a Galilean reference system is similar to the shift freedom in the 3+1-formalism of general relativity. This allows us to write Newton's theory as living in a 4-dimensional Lorentzian manifold $M^N$. This manifold can be chosen to be curved depending on the dynamics of the Newtonian fluid. In this paper, we focus on a specific choice for $M^N$ leading to what we call the textit{1+3-Newton equations}. We show that these equations can be recovered from general relativity with a Newtonian limit performed in the rest frames of the relativistic fluid. The 1+3 formulation of the Newton equations along with the Newtonian limit we introduce also allow us to define a dictionary between Newton's theory and general relativity. This dictionary is defined in the rest frames of the dust fluid, i.e. a non-accelerating observer. A consequence of this is that it is only defined for irrotational fluids. As an example supporting the 1+3-Newton equations and our dictionary, we show that the parabolic free-fall solution in 1+3-Newton exactly translates into the Schwarzschild spacetime, and this without any approximations. The dictionary might then be an additional tool to test the validity of Newtonian solutions with respect to general relativity. It however needs to be further tested for non-vacuum, non-stationary and non-isolated Newtonian solutions, as well as to be adapted for rotational fluids. One of the main applications we consider for the 1+3 formulation of Newton's equations is to define new models suited for the study of backreaction and global topology in cosmology.","PeriodicalId":8455,"journal":{"name":"arXiv: General Relativity and Quantum Cosmology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86392757","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: 5

A geometrical model for the evolution of spherical planetary nebulae based on thin-shell formalism 基于薄壳理论的球形行星状星云演化的几何模型

arXiv: General Relativity and Quantum Cosmology Pub Date : 2020-10-19 DOI: 10.1142/s0219887821501917

S. Forghani, Ibrahim Gullu, S. Mazharimousavi

引用次数: 0

The dark sector cosmology 暗区宇宙学

arXiv: General Relativity and Quantum Cosmology Pub Date : 2020-10-16 DOI: 10.1142/s0218271820300141

E. Abdalla, A. Marins

引用次数: 2

Static spacetimes haunted by a phantom scalar field. III. Asymptotically (A)dS solutions 被虚标量场困扰的静态时空。3渐近(A)dS解

arXiv: General Relativity and Quantum Cosmology Pub Date : 2020-10-15 DOI: 10.1103/PHYSREVD.103.024005

Masato Nozawa

引用次数: 5

Static spacetimes haunted by a phantom scalar field. II. Dilatonic charged solutions 被虚标量场困扰的静态时空。2扩张性带电解

arXiv: General Relativity and Quantum Cosmology Pub Date : 2020-10-15 DOI: 10.1103/physrevd.103.024004

Masato Nozawa

{"title":"Static spacetimes haunted by a phantom scalar field. II. Dilatonic charged solutions","authors":"Masato Nozawa","doi":"10.1103/physrevd.103.024004","DOIUrl":"https://doi.org/10.1103/physrevd.103.024004","url":null,"abstract":"We present a method to generate static solutions in the Einstein-Maxwell system with a (phantom) dilaton field in $n(ge 4)$-dimensions, based upon the symmetry of the target space for the nonlinear sigma model. Unlike the conventional Einstein-Maxwell-dilaton system, there appears a critical value of the coupling constant for a phantom dilaton field. In the noncritical case, the target space is $mathbb Rtimes {rm SL}(2,mathbb R)/H$ with the maximal subgroup $H={{rm SO}(2), {rm SO}(1,1)}$, whereas in the critical case the target space becomes a symmetric pp-wave and the corresponding Killing vectors form a non-semisimple algebra. In either case, we apply the formalism to charge up the neutral solutions and show the analytical expression for dilatonic charged versions of (i) the Fisher solution, (ii) the Gibbons solution, and (iii) the Ellis-Bronnikov solution. We discuss global structures of these solutions in detail. It turns out that some solutions contained in the Fisher and Gibbons classes possess the parallelly propagated (p.p) curvature singularities in the parameter region where all the scalar curvature invariants remain bounded. These p.p curvature singularities are not veiled by a horizon, thrusting them into physically untenable nakedly singular spacetimes. We also demonstrate that the dilatonic-charged Ellis-Bronnikov solution admits a parameter range under which the solution represents a regular wormhole spacetime in the two-sided asymptotically flat regions.","PeriodicalId":8455,"journal":{"name":"arXiv: General Relativity and Quantum Cosmology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76932433","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: 5

Ergoregion instability and echoes for braneworld black holes: Scalar, electromagnetic, and gravitational perturbations 膜世界黑洞的遍历区域不稳定性和回声:标量、电磁和引力摄动

arXiv: General Relativity and Quantum Cosmology Pub Date : 2020-10-15 DOI: 10.1103/PHYSREVD.103.084019

Ramit Dey, Shauvik Biswas, S. Chakraborty

{"title":"Ergoregion instability and echoes for braneworld black holes: Scalar, electromagnetic, and gravitational perturbations","authors":"Ramit Dey, Shauvik Biswas, S. Chakraborty","doi":"10.1103/PHYSREVD.103.084019","DOIUrl":"https://doi.org/10.1103/PHYSREVD.103.084019","url":null,"abstract":"In the context of higher dimensional braneworld scenario, we have argued that the occurrence of horizonless exotic compact objects, as an alternative to classical black holes, are more natural. These exotic compact objects carry a distinctive signature of the higher dimension, namely a tidal charge parameter, inherited from the projection of the higher dimensional Weyl tensor onto the four dimensional spacetime we live in. Due to the absence of any horizon, rotating exotic compact objects are often unstable because of superradiance. Interestingly, these higher dimensional exotic compact objects, in the presence of the tidal charge, are more stable than their four dimensional counterpart. A similar inference is drawn by analysing the static modes associated with these exotic compact objects, irrespective of the nature of the perturbation i.e., it holds true for scalar, electromagnetic and also gravitational perturbation. The post-merger ringdown phase of the exotic compact object in the braneworld scenario, which can be described in terms of the quasi-normal modes, holds plethora of information regarding the nature of the higher dimension. In this connection we have discussed the analytical computation of the quasi-normal modes as well as their numerical estimation for perturbations of arbitrary spin, depicting existence of echoes in the ringdown waveform. As we have demonstrated, the echoes in the ringdown waveform depends explicitly on the tidal charge parameter and hence its future detection can provide constraints on the tidal charge parameter, which in turn will enable us to provide a possible bound on the length of the extra dimension.","PeriodicalId":8455,"journal":{"name":"arXiv: General Relativity and Quantum Cosmology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76587658","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: 23

Bounce models within teleparallel modified gravity 遥平行修正重力下的弹跳模型

arXiv: General Relativity and Quantum Cosmology Pub Date : 2020-10-15 DOI: 10.1103/physrevd.103.023514

A. Casalino, Bruno Sanna, L. Sebastiani, S. Zerbini

引用次数: 5