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Related papers: Energy Conditions and Cosmic Acceleration

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In order to constrain $f(R,L_{m})$ gravity from theoretical aspects, its energy conditions are derived in this paper. These energy conditions given by us are quite general and can be degenerated to the well-known energy conditions in…

General Physics · Physics 2015-06-12 Jun Wang , Kai Liao

In our study, we explored the properties of a spatially homogeneous and anisotropic Bianchi type V I0 Universe. Our investigation centered on integrating cosmic domain walls into the f(R, T) theory of gravitation, initially proposed by…

General Relativity and Quantum Cosmology · Physics 2024-03-05 V. R. Patil , J. L. Pawde , R. V. Mapari , S. K. Waghmare

In this study, we explore the cosmological implications of a modified gravity theory characterized by the function \( f(R, \Sigma, T) \), where \( R \) is the Ricci scalar, \( \Sigma \) represents a geometric deformation term, and \( T \)…

General Relativity and Quantum Cosmology · Physics 2026-01-06 N. Myrzakulov , S. H. Shekh , S. R. Bhoyar , Anirudh Pradhan

The present paper is elaborated to discuss the energy condition bounds in a modified teleparallel gravity namely $F(T,T_{G})$, involving torsion invariant $T$ and contribution from a term $T_G$, the teleparallel equivalent of the…

General Relativity and Quantum Cosmology · Physics 2015-09-23 Saira Waheed , M. Zubair

The energy conditions provide a very promising model-independent study of the current acceleration of the universe. However, in order to connect these conditions with observations, one often needs first to integrate them, and then find the…

Astrophysics · Physics 2009-06-23 Yungui Gong , Anzhong Wang

New observational constraints on the cosmic matter density $\Omega_m$ and an effectively redshift-independent equation of state parameter $w_x$ of the dark energy are obtained while simultaneously testing the strong and null energy…

Recent discoveries in the field of observational cosmology have provided increasing evidence that the Universe is undergoing a late time acceleration, which has also stimulated speculations on the nature of the dark component responsible…

Astrophysics · Physics 2009-11-10 J. Santos , J. S. Alcaniz

We examine the validity of classical energy conditions in nonsingular bouncing cosmological solutions arising in quadratic curvature gravity minimally coupled to a scalar field. Focusing on the null, weak, strong, and dominant energy…

General Relativity and Quantum Cosmology · Physics 2026-04-30 Yuki Hashimoto , Kazuharu Bamba , Sanjay Mandal

An energy condition, in the context of a wide class of spacetime theories (including general relativity), is, crudely speaking, a relation one demands the stress-energy tensor of matter satisfy in order to try to capture the idea that…

History and Philosophy of Physics · Physics 2021-03-04 Erik Curiel

In the context of f(R, T) gravity theory for the flat Friedmann Lemaitre Robertson Walker (FLRW) model, the accelerating expansion of the universe is investigated using a specific form of the emergent Hubble parameter. Datasets from H(z),…

General Relativity and Quantum Cosmology · Physics 2025-01-16 N. Myrzakulov , S. H. Shekh , Anirudh Pradhan , Archana Dixit

In this paper, we consider the flat Friedmann Lematre Robertson-Walke metric in the presence of perfect fluid models and extended $f(R,G,T)$ gravity (where $R$ is the Ricci scalar, $G$ is the Gauss Bonnet invariant and $T$ stands for trace…

General Relativity and Quantum Cosmology · Physics 2022-12-21 M. Ilyas , Aftab Ahmad , Fawad Khan , M. Wasif

There has been recent interest in the cosmological consequences of energy-momentum-powered gravity models, in which the matter side of Einstein's equations is modified by the addition of a term proportional to some power, $n$, of the…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-29 M. C. F. Faria , C. J. A. P. Martins , F. Chiti , B. S. A. Silva

The present paper examines the validity of energy bounds in a modified theory of gravity involving non-minimal coupling of torsion scalar and perfect fluid matter. In this respect, we formulate the general inequalities of energy conditions…

General Relativity and Quantum Cosmology · Physics 2015-02-11 M. Zubair , Saira Waheed

Exploiting the existence of two "cosmological" constants, one associated with the classical Lovelock theorem and one with the vacuum energy density, we argue, in a model independent way, that in spatially closed FLRW cosmologies with a…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Benjamin K. Tippett , Kayll Lake

As a rule in General Relativity the spacetime metric fixes the Einstein tensor and through the Field Equations (FE) the energy-momentum tensor. However one cannot write the FE explicitly until a class of observers has been considered. Every…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Pantelis S. Apostolopoulos , Michael Tsamparlis

In this paper, we examine the acceleration of the Universe's expansion in $F(R,T)$ gravity, where $R$ denotes the Ricci scalar and $T$ the trace of energy-momentum tensor. Indeed, the unknown nature of the source controlling this…

General Relativity and Quantum Cosmology · Physics 2024-04-25 Ahmed Errahmani , Amine Bouali , Safae Dahmani , Imad El Bojaddaini , Taoufik Ouali

We refine and extend a programme initiated by one of the current authors [Science 276 (1997) 88; Phys. Rev. D56 (1997) 7578] advocating the use of the classical energy conditions of general relativity in a cosmological setting to place very…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Celine Cattoen , Matt Visser

We obtain the analogues of the Friedman equations in an emergent gravity scenario in the presence of dark energy. The background metric is taken to be Friedman-Lemaitre-Robertson-Walker (FLRW). We show that if $\dot\phi ^{2}$ is the dark…

General Relativity and Quantum Cosmology · Physics 2015-02-24 Debashis Gangopadhyay , Goutam Manna

In model building studies, it is important to check the energy conditions for the corresponding energy-momentum tensor determined by the gravitational field equations in order to single out physically reasonable models. In this process, one…

General Relativity and Quantum Cosmology · Physics 2022-09-02 Hideki Maeda , Tomohiro Harada

This review summarizes the current status of the energy conditions in general relativity and quantum field theory. We provide a historical review and a summary of technical results and applications, complemented with a few new derivations…

General Relativity and Quantum Cosmology · Physics 2020-06-08 Eleni-Alexandra Kontou , Ko Sanders