{"title":"$$\\boldsymbol{f(R,T)}$$ 引力宇宙学","authors":"I. S. Farias, P. H. R. S. Moraes","doi":"10.1134/S0202289324010055","DOIUrl":null,"url":null,"abstract":"<p>Currently, in order to explain the accelerated expansion phase of the Universe, several alternative approaches have been proposed, among which the most common are dark energy models and alternative theories of gravity. Although these approaches rest on very different physical aspects, it has been shown that both can be in agreement with the data in the current status of cosmological observations, thus leading to an enormous degeneration among these models. Therefore, until evidence of higher experimental accuracy is available, more conservative model-independent approaches are a useful tool for breaking this degenerated cosmological models picture. Cosmography as a kinematic study of the Universe is the most popular candidate in this regard. In this paper, we show how to construct the cosmographic equations for the <span>\\(f(R,T)\\)</span> theory of gravity within a conservative scenario of this theory, where <span>\\(R\\)</span> is the Ricci curvature scalar, and <span>\\(T\\)</span> is the trace of the energy-moment tensor. Such equations relate the <span>\\(f(R,T)\\)</span> function and its derivatives at current time <span>\\(t_{0}\\)</span> to the cosmographic parameters <span>\\(q_{0}\\)</span>, <span>\\(j_{0}\\)</span>, and <span>\\(s_{0}\\)</span>. In addition, we show how these equations can be written within different dark energy scenarios, thus helping to discriminate among them. We also show how different <span>\\(f(R,T)\\)</span> gravity models can be constrained using these cosmographic equations.</p>","PeriodicalId":583,"journal":{"name":"Gravitation and Cosmology","volume":null,"pages":null},"PeriodicalIF":1.2000,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Cosmography of \\\\(\\\\boldsymbol{f(R,T)}\\\\) Gravity\",\"authors\":\"I. S. Farias, P. H. R. S. Moraes\",\"doi\":\"10.1134/S0202289324010055\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>Currently, in order to explain the accelerated expansion phase of the Universe, several alternative approaches have been proposed, among which the most common are dark energy models and alternative theories of gravity. Although these approaches rest on very different physical aspects, it has been shown that both can be in agreement with the data in the current status of cosmological observations, thus leading to an enormous degeneration among these models. Therefore, until evidence of higher experimental accuracy is available, more conservative model-independent approaches are a useful tool for breaking this degenerated cosmological models picture. Cosmography as a kinematic study of the Universe is the most popular candidate in this regard. In this paper, we show how to construct the cosmographic equations for the <span>\\\\(f(R,T)\\\\)</span> theory of gravity within a conservative scenario of this theory, where <span>\\\\(R\\\\)</span> is the Ricci curvature scalar, and <span>\\\\(T\\\\)</span> is the trace of the energy-moment tensor. Such equations relate the <span>\\\\(f(R,T)\\\\)</span> function and its derivatives at current time <span>\\\\(t_{0}\\\\)</span> to the cosmographic parameters <span>\\\\(q_{0}\\\\)</span>, <span>\\\\(j_{0}\\\\)</span>, and <span>\\\\(s_{0}\\\\)</span>. In addition, we show how these equations can be written within different dark energy scenarios, thus helping to discriminate among them. We also show how different <span>\\\\(f(R,T)\\\\)</span> gravity models can be constrained using these cosmographic equations.</p>\",\"PeriodicalId\":583,\"journal\":{\"name\":\"Gravitation and Cosmology\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.2000,\"publicationDate\":\"2024-04-04\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Gravitation and Cosmology\",\"FirstCategoryId\":\"4\",\"ListUrlMain\":\"https://link.springer.com/article/10.1134/S0202289324010055\",\"RegionNum\":4,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"ASTRONOMY & ASTROPHYSICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Gravitation and Cosmology","FirstCategoryId":"4","ListUrlMain":"https://link.springer.com/article/10.1134/S0202289324010055","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ASTRONOMY & ASTROPHYSICS","Score":null,"Total":0}
Currently, in order to explain the accelerated expansion phase of the Universe, several alternative approaches have been proposed, among which the most common are dark energy models and alternative theories of gravity. Although these approaches rest on very different physical aspects, it has been shown that both can be in agreement with the data in the current status of cosmological observations, thus leading to an enormous degeneration among these models. Therefore, until evidence of higher experimental accuracy is available, more conservative model-independent approaches are a useful tool for breaking this degenerated cosmological models picture. Cosmography as a kinematic study of the Universe is the most popular candidate in this regard. In this paper, we show how to construct the cosmographic equations for the \(f(R,T)\) theory of gravity within a conservative scenario of this theory, where \(R\) is the Ricci curvature scalar, and \(T\) is the trace of the energy-moment tensor. Such equations relate the \(f(R,T)\) function and its derivatives at current time \(t_{0}\) to the cosmographic parameters \(q_{0}\), \(j_{0}\), and \(s_{0}\). In addition, we show how these equations can be written within different dark energy scenarios, thus helping to discriminate among them. We also show how different \(f(R,T)\) gravity models can be constrained using these cosmographic equations.
期刊介绍:
Gravitation and Cosmology is a peer-reviewed periodical, dealing with the full range of topics of gravitational physics and relativistic cosmology and published under the auspices of the Russian Gravitation Society and Peoples’ Friendship University of Russia. The journal publishes research papers, review articles and brief communications on the following fields: theoretical (classical and quantum) gravitation; relativistic astrophysics and cosmology, exact solutions and modern mathematical methods in gravitation and cosmology, including Lie groups, geometry and topology; unification theories including gravitation; fundamental physical constants and their possible variations; fundamental gravity experiments on Earth and in space; related topics. It also publishes selected old papers which have not lost their topicality but were previously published only in Russian and were not available to the worldwide research community