General Relativity and Gravitation最新文献_第10页

Vacuum polarization on three-dimensional anti-de Sitter space-time with Robin boundary conditions 具有Robin边界条件的三维反德西特时空的真空极化

IF 2.8 4区物理与天体物理

General Relativity and Gravitation Pub Date : 2023-01-04 DOI: 10.1007/s10714-022-03056-6

Sivakumar Namasivayam, Elizabeth Winstanley

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引用次数: 2

Modified Brans–Dicke cosmology with minimum length uncertainty 最小长度不确定性的修正Brans-Dicke宇宙论

IF 2.8 4区物理与天体物理

General Relativity and Gravitation Pub Date : 2023-01-02 DOI: 10.1007/s10714-022-03059-3

Andronikos Paliathanasis, Genly Leon

引用次数: 2

Comparing phantom dark energy models with various diagnostic tools 比较幻影暗能量模型与各种诊断工具

IF 2.8 4区物理与天体物理

General Relativity and Gravitation Pub Date : 2022-12-29 DOI: 10.1007/s10714-022-03055-7

Dalale Mhamdi, Farida Bargach, Safae Dahmani, Amine Bouali, Taoufik Ouali

{"title":"Comparing phantom dark energy models with various diagnostic tools","authors":"Dalale Mhamdi, Farida Bargach, Safae Dahmani, Amine Bouali, Taoufik Ouali","doi":"10.1007/s10714-022-03055-7","DOIUrl":"10.1007/s10714-022-03055-7","url":null,"abstract":"<div>In this paper, we apply various diagnostic tools to the phantom dark energy (DE) models, including the big rip (BR), the little sibling of the big rip (LSBR), and the little rip (LR). The evolutionary trajectories of the statefinder (S_{n}(z)), the growth rate (epsilon (z)), and both Om(z) and (omega _{d}-omega {}'_{d}) diagnostics are plotted according to the best fit extracted from each model using a Markov Chain Monte Carlo method. In the high-redshift region, all these diagnostics show the degeneracy of the phantom DE models with each other and also with the (Lambda )CDM model, even considering cases of different parameter values shows strong degeneracy. However, in the low-redshift region this degeneracy was broken by using (S_{3}^{(1)}) and (S_{4}^{(1)}) diagnostics, or otherwise by using the composite null diagnostic (CND). All diagnostic tools show the rich behavior of the LSBR model as it can be quintessence-like or phantom-like depending on the (Omega _{lsbr}) parameter, in contrast to the LR model which is only phantom-like. A direct comparison of the phantom DE models in the (left{ {S_{3}^{(1)}, S_{4}^{(1)}} right} ), (left{ {S_{3}^{(1)}, S_{3}^{(2)}} right} ), and (omega _{d}-omega {}'_{d}) plane is also made. We further show that the separation between the models can be directly seen at the current state (left{ S_{3}^{(1)}(t_{0}),S_{4}^{(1)}(t_{0}) right} ) of the models. We have reached that these diagnostic tools are rather robust in differentiating not only different DE models but also the same kind of models with different equation of state (EoS) which lead to different fates of the Universe.</div>","PeriodicalId":578,"journal":{"name":"General Relativity and Gravitation","volume":"55 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2022-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10714-022-03055-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"5115095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Anisotropic compact stars with Karmarkar condition in energy-momentum squared gravity 能量动量平方重力下Karmarkar条件下各向异性致密恒星

IF 2.8 4区物理与天体物理

General Relativity and Gravitation Pub Date : 2022-12-28 DOI: 10.1007/s10714-022-03062-8

M. Sharif, M. Zeeshan Gul

引用次数: 4

Black-bounce in f(T) gravity f(T)重力下的黑弹

IF 2.8 4区物理与天体物理

General Relativity and Gravitation Pub Date : 2022-12-28 DOI: 10.1007/s10714-022-03048-6

Manuel E. Rodrigues, Ednaldo L. B. Junior

引用次数: 7

The Jacobi metric approach for dynamical wormholes 动态虫洞的Jacobi度量方法

IF 2.8 4区物理与天体物理

General Relativity and Gravitation Pub Date : 2022-12-28 DOI: 10.1007/s10714-022-03060-w

Álvaro Duenas-Vidal, Oscar Lasso Andino

引用次数: 1

The averaging problem on the past null cone in inhomogeneous dust cosmologies 非均匀尘埃宇宙学中过去零锥的平均问题

IF 2.8 4区物理与天体物理

General Relativity and Gravitation Pub Date : 2022-12-27 DOI: 10.1007/s10714-022-03051-x

Thomas Buchert, Henk van Elst, Asta Heinesen

{"title":"The averaging problem on the past null cone in inhomogeneous dust cosmologies","authors":"Thomas Buchert, Henk van Elst, Asta Heinesen","doi":"10.1007/s10714-022-03051-x","DOIUrl":"10.1007/s10714-022-03051-x","url":null,"abstract":"<div>Cosmological models typically neglect the complicated nature of the spacetime mani-fold at small scales in order to hypothesize idealized general relativistic solutions for describing the average dynamics of the Universe. Although these solutions are remarkably successful in accounting for data, they introduce a number of puzzles in cosmology, and their foundational assumptions are therefore important to test. In this paper, we go beyond the usual assumptions in cosmology and propose a formalism for averaging the local general relativistic spacetime on an observer’s past null cone: we formulate average properties of light fronts as they propagate from a cosmological emitter to an observer. The energy-momentum tensor is composed of an irrotational dust source and a cosmological constant—the same components as in the (varLambda )CDM model for late cosmic times—but the metric solution is not a priori constrained to be locally homogeneous or isotropic. This generally makes the large-scale dynamics depart from that of a simple Friedmann–Lemaître–Robertson–Walker solution through ‘backreaction’ effects. Our formalism quantifies such departures through a fully covariant system of area-averaged equations on the light fronts propagating towards an observer, which can be directly applied to analytical and numerical investigations of cosmic observables. For this purpose, we formulate light front averages of observable quantities, including the effective angular diameter distance and the cosmological redshift drift and we also discuss the backreaction effects for these observables.</div>","PeriodicalId":578,"journal":{"name":"General Relativity and Gravitation","volume":"55 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2022-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10714-022-03051-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"5034472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 10

Damped modes for a bosonic quantum oscillator in the near-horizon geometry of the BTZ black hole BTZ黑洞近视界几何中玻色子量子振荡器的阻尼模式

IF 2.8 4区物理与天体物理

General Relativity and Gravitation Pub Date : 2022-12-26 DOI: 10.1007/s10714-022-03058-4

Abdullah Guvendi, Semra Gurtas Dogan

引用次数: 4

Normal modes of Proca fields in AdS spacetime AdS时空中Proca场的正常模式

IF 2.8 4区物理与天体物理

General Relativity and Gravitation Pub Date : 2022-12-25 DOI: 10.1007/s10714-022-03052-w

Tiago V. Fernandes, David Hilditch, José P. S. Lemos, Vítor Cardoso

引用次数: 1

Microstructure of five-dimensional neutral Gauss–Bonnet black hole in anti-de Sitter spacetime via (P-V) criticality 反德西特时空中五维中性高斯- bonnet黑洞的P-V临界微结构

IF 2.8 4区物理与天体物理

General Relativity and Gravitation Pub Date : 2022-12-22 DOI: 10.1007/s10714-022-03050-y

A. Naveena Kumara, C. L. Ahmed Rizwan, Kartheek Hegde, Md Sabir Ali, K. M. Ajith

引用次数: 7