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We perform the dynamical system analysis of a cosmological model in the energy-momentum squared gravity (EMSG) of the form $f(T_{\mu\nu} T^{\mu\nu})=\alpha\ln({\lambda}T_{\mu\nu} T^{\mu\nu})$, which is known as energy-momentum log gravity…

General Relativity and Quantum Cosmology · Physics 2025-07-02 Giovanni Acquaviva , Nihan Katirci

We explore the weak field and slow motion limits, Newtonian and Post-Newtonian limits, of the energy-momentum powered gravity (EMPG), viz., the energy-momentum squared gravity (EMSG) of the form $f(T_{\mu\nu}T^{\mu\nu})=\alpha…

General Relativity and Quantum Cosmology · Physics 2023-08-21 Ozgur Akarsu , A. Kazim Camlibel , Nihan Katirci , Ibrahim Semiz , N. Merve Uzun

We propose a modified theory of gravitation constructed by the addition of the term $f(T_{\mu\nu}T^{\mu\nu})$ to the Einstein-Hilbert action, and elaborate a particular case $f(T_{\mu\nu}T^{\mu\nu})=\alpha(T_{\mu\nu}T^{\mu\nu})^{\eta}$,…

General Relativity and Quantum Cosmology · Physics 2018-02-09 Ozgur Akarsu , Nihan Katirci , Suresh Kumar

In this work, we present a review of Energy-Momentum Squared Gravity (EMSG) -- more specifically, $f(R,T_{\mu\nu}T^{\mu\nu})$ gravity, where $R$ represents the Ricci scalar and $T_{\mu\nu}$ denotes the energy-momentum tensor. The inclusion…

General Relativity and Quantum Cosmology · Physics 2024-08-27 Ricardo A. C. Cipriano , Nailya Ganiyeva , Tiberiu Harko , Francisco S. N. Lobo , Miguel A. S. Pinto , João Luís Rosa

We construct a generalization of the standard $\Lambda$CDM model, wherein we simultaneously replace the spatially flat Robertson-Walker metric with its simplest anisotropic generalization (LRS Bianchi I metric), and couple the cold dark…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-01 Ozgur Akarsu , John D. Barrow , N. Merve Uzun

A simple generalization to Einstein's general relativity (GR) was recently proposed which allows a correction term $T_{\alpha\beta}T^{\alpha\beta}$ in the action functional of the theory. This theory is called Energy-Momentum Squared…

General Relativity and Quantum Cosmology · Physics 2018-07-25 Nasrin Nari , Mahmood Roshan

Employing the spherical collapse (SC) formalism, we investigate the linear evolution of the matter over-density for energy-momentum-squared gravity (EMSG), which in practical phenomenological terms, one may imagine as an extension of the…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-26 Bita Farsi , Ahmad Sheykhi , Mohsen Khodadi

In this paper, we introduce a scale-independent energy-momentum squared gravity (EMSG) that allows different gravitational couplings for different types of sources, which may lead to scenarios with many interesting applications/implications…

General Relativity and Quantum Cosmology · Physics 2018-09-25 Ozgur Akarsu , Nihan Katirci , Suresh Kumar , Rafael C. Nunes , M. Sami

We investigate the linear cosmological perturbations in the context of the so-called energy-momentum squared gravity (EMSG) theory. Recent researches show that the EMSG theory can reproduce viable background cosmological evolution…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-17 Qi-Ming Fu , Xin Zhang

We consider a model of early modified gravity (EMG) that was recently proposed as a candidate to resolve the Hubble tension. The model consists in a scalar field $\sigma$ with a non-minimal coupling (NMC) to the Ricci curvature of the form…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-14 Guillermo Franco Abellán , Matteo Braglia , Mario Ballardini , Fabio Finelli , Vivian Poulin

Energy Momentum Squared Gravity (EMSG) is a cosmological model where the scale factor is non vanishing at all times and hence does not favor big bang cosmology. However, the profile of density in the radiation dominated universe shows that…

General Relativity and Quantum Cosmology · Physics 2020-01-22 S. Bhattacharjee , P. K. Sahoo

In the present work, we derive the motion of light in the weak-field limit of energy-momentum-squared gravity (EMSG). To do so, we introduce the post-Newtonian (PN) expansion of this modified theory of gravity. It is shown that in addition…

General Relativity and Quantum Cosmology · Physics 2022-05-25 Elham Nazari

Neutron stars (NSs), superdense objects with exceptionally strong gravitational fields, provide an ideal laboratory for probing general relativity (GR) in the high-curvature regime. They also present an exciting opportunity to explore new…

General Relativity and Quantum Cosmology · Physics 2026-02-02 Sayantan Ghosh

Deviations from the predictions of general relativity due to energy-momentum squared gravity (EMSG) are expected to become pronounced in the high density cores of neutron stars. We derive the hydrostatic equilibrium equations in EMSG and…

General Relativity and Quantum Cosmology · Physics 2018-06-12 Ozgur Akarsu , John D. Barrow , Sercan Çıkıntoğlu , K. Yavuz Ekşi , Nihan Katirci

In this work, we analyze the possibility of gravitationally induced matter creation in the so-called Energy-Momentum-Squared gravity (EMSG), i.e. $f(R,T_{\mu\nu}T^{\mu\nu})$ gravity, in its dynamically equivalent scalar-tensor…

General Relativity and Quantum Cosmology · Physics 2024-03-15 Ricardo A. C. Cipriano , Tiberiu Harko , Francisco S. N. Lobo , Miguel A. S. Pinto , João Luís Rosa

We present a model of Early Modified Gravity (EMG) consisting in a scalar field $\sigma$ with a non-minimal coupling to the Ricci curvature of the type $M^2_{\rm pl}+\xi \sigma^2$ plus a cosmological constant and a small effective mass and…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-24 Matteo Braglia , Mario Ballardini , Fabio Finelli , Kazuya Koyama

Scale-independent EMSG is a particular model of energy-momentum squared gravity (EMSG) in which the new terms in the Einstein field equations arising from the EMSG theory enter with the same power as the usual terms from Einstein-Hilbert…

General Relativity and Quantum Cosmology · Physics 2023-02-24 Ozgur Akarsu , N. Merve Uzun

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

In this work, we investigate a cosmological scenario with a time-dependent cosmological constant $\Lambda$(t) within the spatially flat Friedmann-Lema\^itre-Robertson-Walker (FLRW) framework. Here we study a power-law $\Lambda(t)$CDM model…

General Relativity and Quantum Cosmology · Physics 2025-10-28 Archana Dixit , Manish Yadav , Anirudh Pradhan , M. S. Barak

Scale-independent energy-momentum squared gravity (EMSG) allows different gravitational couplings for different types of sources and has been proven to have interesting implications in cosmology. In this paper, the Big Bang Nucleosynthesis…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-26 Dukjae Jang , Mayukh R. Gangopadhyay , Myung-Ki Cheoun , Toshitaka Kajino , M. Sami
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