Dark energy and the accelerating Universe: conceptual aspects and observational tests
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Author(s): 
Total Authors: 4

Affiliation:  ^{[1]} Birla Inst Technol & Sci Pilani, Dept Math, Hyderabad Campus, Hyderabad 500078  India
^{[2]} ITA, Dept Fis, BR12228900 Sao Jose Dos Campos, SP  Brazil
^{[3]} Lovely Profess Univ, Dept Math, Jalandhar 144401, Punjab  India
Total Affiliations: 3

Document type:  Journal article 
Source:  EUROPEAN PHYSICAL JOURNAL C; v. 78, n. 9 SEP 15 2018. 
Web of Science Citations:  0 
Abstract  
This article presents cosmological models that arise in a subclass of f (R, T) = f(R) + f (T) gravity models, with different f (R) functions and fixed Tdependence. That is, the gravitational lagrangian is considered as f (R, T) = f (R) + lambda T, with constant lambda. Here R and T represent the Ricci scalar and trace of the stressenergy tensor, respectively. The modified gravitational field equations are obtained through the metric formalism for the FriedmannLemaitreRobertsonWalker metric with signature (+,, , ). We work with f (R) = R + alpha R2 mu(4)/R, f (R) = R + k ln(gamma R) and f (R) = R + me({[}nR]), with alpha, mu, k, gamma, m and n all free parameters, which lead to three different cosmological models for our Universe. For the choice of lambda = 0, this reduces to widely discussed f (R) gravity models. This manuscript clearly describes the effects of adding the trace of the energymomentum tensor in the f (R) lagrangian. The exact solution of the modified field equations are obtained under the hybrid expansion law. Also we present the Om diagnostic analysis for the discussed models. (AU)  
FAPESP's process:  15/084760  Gravitational waves in f(R,T) theories: polarization states and astrophysical sources 
Grantee:  Pedro Henrique Ribeiro da Silva Moraes 
Support type:  Scholarships in Brazil  PostDoctorate 