{"title":"f(R,T)引力下的受约束加速宇宙","authors":"J.K. Singh, H. Balhara, Shaily, P. Singh","doi":"10.1016/j.ascom.2024.100795","DOIUrl":null,"url":null,"abstract":"<div><p>In this paper, we study an alternative phenomenological model in <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>R</mi><mo>,</mo><mi>T</mi><mo>)</mo></mrow></mrow></math></span> gravity, where <span><math><mi>R</mi></math></span> indicates Ricci scalar curvature and <span><math><mi>T</mi></math></span> is the trace of the stress–energy–momentum tensor consisting of a modification in General Relativity, to explain the dynamics of a dark energy model at cosmological scales employed in a flat universe. Our basic concept is to create a model to analyze the behavior of the Universe right from early evolution up to its ultimate fate, which is an accelerated expansion in late times. Using the parametrization of the Hubble parameter <span><math><mi>H</mi></math></span>, we find a model, that begins with infinite energy density and infinite pressure and shows accelerating expansion in late times. We concentrate on contrasting this model with the most recent cosmological observations of the Hubble parameter (77 data points) and Pantheon measurements (1048 data points). Our joint analysis yields the present values of the free model parameter <span><math><mrow><mn>0</mn><mo>.</mo><mn>77</mn><msubsup><mrow><mn>6</mn></mrow><mrow><mo>−</mo><mn>0</mn><mo>.</mo><mn>014</mn></mrow><mrow><mo>+</mo><mn>0</mn><mo>.</mo><mn>014</mn></mrow></msubsup></mrow></math></span> and Hubble parameter <span><math><mrow><mn>71</mn><mo>.</mo><mn>3</mn><msubsup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>0</mn><mo>.</mo><mn>25</mn></mrow><mrow><mo>+</mo><mn>0</mn><mo>.</mo><mn>66</mn></mrow></msubsup></mrow></math></span> for a flat universe. Finally, we conclude that our model behaves like a quintessence dark energy model in late times and is in good agreement with the recent observations.</p></div>","PeriodicalId":48757,"journal":{"name":"Astronomy and Computing","volume":"46 ","pages":"Article 100795"},"PeriodicalIF":1.9000,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2213133724000106/pdfft?md5=b2c85d12862e5b2f4900684a67eb6639&pid=1-s2.0-S2213133724000106-main.pdf","citationCount":"0","resultStr":"{\"title\":\"The constrained accelerating universe in f(R,T) gravity\",\"authors\":\"J.K. Singh, H. Balhara, Shaily, P. 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Using the parametrization of the Hubble parameter <span><math><mi>H</mi></math></span>, we find a model, that begins with infinite energy density and infinite pressure and shows accelerating expansion in late times. We concentrate on contrasting this model with the most recent cosmological observations of the Hubble parameter (77 data points) and Pantheon measurements (1048 data points). Our joint analysis yields the present values of the free model parameter <span><math><mrow><mn>0</mn><mo>.</mo><mn>77</mn><msubsup><mrow><mn>6</mn></mrow><mrow><mo>−</mo><mn>0</mn><mo>.</mo><mn>014</mn></mrow><mrow><mo>+</mo><mn>0</mn><mo>.</mo><mn>014</mn></mrow></msubsup></mrow></math></span> and Hubble parameter <span><math><mrow><mn>71</mn><mo>.</mo><mn>3</mn><msubsup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>0</mn><mo>.</mo><mn>25</mn></mrow><mrow><mo>+</mo><mn>0</mn><mo>.</mo><mn>66</mn></mrow></msubsup></mrow></math></span> for a flat universe. 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引用次数: 0
摘要
本文研究了f(R,T)引力中的另一种现象学模型,其中R表示里奇标量曲率,T是广义相对论中修正的应力-能量-动量张量的迹线,用以解释平坦宇宙中宇宙学尺度的暗能量模型的动力学。我们的基本概念是创建一个模型来分析宇宙从早期演化到最终命运(即晚期加速膨胀)的行为。利用哈勃参数 H 的参数化,我们找到了一个模型,它从无限能量密度和无限压力开始,在晚期表现出加速膨胀。我们将这个模型与最新的哈勃参数宇宙学观测数据(77 个数据点)和万神殿测量数据(1048 个数据点)进行对比。通过联合分析,我们得出了平坦宇宙的自由模型参数 0.776-0.014+0.014 和哈勃参数 71.30-0.25+0.66 的现值。最后,我们得出结论,我们的模型在晚期表现得像一个五重暗能量模型,并且与最近的观测结果十分吻合。
The constrained accelerating universe in f(R,T) gravity
In this paper, we study an alternative phenomenological model in gravity, where indicates Ricci scalar curvature and is the trace of the stress–energy–momentum tensor consisting of a modification in General Relativity, to explain the dynamics of a dark energy model at cosmological scales employed in a flat universe. Our basic concept is to create a model to analyze the behavior of the Universe right from early evolution up to its ultimate fate, which is an accelerated expansion in late times. Using the parametrization of the Hubble parameter , we find a model, that begins with infinite energy density and infinite pressure and shows accelerating expansion in late times. We concentrate on contrasting this model with the most recent cosmological observations of the Hubble parameter (77 data points) and Pantheon measurements (1048 data points). Our joint analysis yields the present values of the free model parameter and Hubble parameter for a flat universe. Finally, we conclude that our model behaves like a quintessence dark energy model in late times and is in good agreement with the recent observations.
Astronomy and ComputingASTRONOMY & ASTROPHYSICSCOMPUTER SCIENCE,-COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS
CiteScore
4.10
自引率
8.00%
发文量
67
期刊介绍:
Astronomy and Computing is a peer-reviewed journal that focuses on the broad area between astronomy, computer science and information technology. The journal aims to publish the work of scientists and (software) engineers in all aspects of astronomical computing, including the collection, analysis, reduction, visualisation, preservation and dissemination of data, and the development of astronomical software and simulations. The journal covers applications for academic computer science techniques to astronomy, as well as novel applications of information technologies within astronomy.