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We use Big Bang Nucleosynthesis (BBN) data in order to impose constraints on higher-order modified gravity, and in particular on: (i) $f(G)$ Gauss-Bonnet gravity, and $f(P)$ cubic gravities, arising respectively through the use of the…

General Relativity and Quantum Cosmology · Physics 2022-04-11 Petros Asimakis , Spyros Basilakos , Nick E. Mavromatos , Emmanuel N. Saridakis

In this work, we extend the standard cosmological model within the quadratic energy-momentum squared gravity (qEMSG) framework, introducing a nonminimal interaction between the usual material field ($T_{\mu\nu}$) and its accompanying…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-26 Ozgur Akarsu , Mariam Bouhmadi-López , Nihan Katirci , N. Merve Uzun

We confront $f(T,T_G)$ gravity, with Big Bang Nucleosynthesis (BBN) requirements. The former is obtained using both the torsion scalar, as well as the teleparallel equivalent of the Gauss-Bonnet term, in the Lagrangian, resulting to…

General Relativity and Quantum Cosmology · Physics 2022-09-20 Petros Asimakis , Emmanuel N. Saridakis , Spyros Basilakos , Kuralay Yesmakhanova

In this work, we investigate Big Bang Nucleosynthesis (BBN) within the framework of $f(T,{L}_m)$ gravity, where the gravitational Lagrangian is generalized as a function of the torsion scalar $T$ and the matter Lagrangian ${L}_m$. We…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-25 Daniel F. P. Cruz , David S. Pereira , Francisco S. N. Lobo , José P. Mimoso

Big Bang Nucleosynthesis provides us with an observational insight into the very early Universe. Since this mechanism of light element synthesis comes out of the standard model of particle cosmology which follows directly from General…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-14 Sai Swagat Mishra , Ameya Kolhatkar , P. K. Sahoo

The $f(Q)$ theories of modified gravity arise from the consideration of non-metricity as the basic geometric quantity, and have been proven to be very efficient in describing the late-time Universe. We use the Big Bang Nucleosynthesis (BBN)…

General Relativity and Quantum Cosmology · Physics 2023-02-08 Fotios K. Anagnostopoulos , Viktor Gakis , Emmanuel N. Saridakis , Spyros Basilakos

The modified gravity is considered to be one of possible explanations of the accelerated expansions of the present and the early universe. We study effects of the modified gravity on big bang nucleosynthesis (BBN). If effects of the…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-23 Motohiko Kusakabe , Seoktae Koh , K. S. Kim , Myung-Ki Cheoun

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

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

In conventional general relativity, the expansion rate H of a Robertson-Walker universe is related to the energy density by the Friedmann equation. Aside from the present day, the only epoch at which we can constrain the expansion history…

Astrophysics · Physics 2014-10-13 Sean M. Carroll , Manoj Kaplinghat

Using big bang nucleosynthesis and present, high-precision measurements of light element abundances, we constrain the self-gravity of radiation pressure in the early universe. The self-gravity of pressure is strictly non-Newtonian, and thus…

Astrophysics · Physics 2008-11-26 Saul Rappaport , Josiah Schwab , Scott Burles , Gary Steigman

Big Bang Nucleosynthesis (BBN) is studied within the framework of a two-parameter family of tensor-scalar theories of gravitation, with nonlinear scalar-matter coupling function a(phi). We run a BBN code modified by tensor-scalar gravity,…

Astrophysics · Physics 2009-10-30 Thibault Damour , Bernard Pichon

A cosmological model with a time-varying mass of electrons seems a promising solution for the so-called Hubble tension. We examine the big bang nucleosynthesis (BBN) constraints on the time-varying electron mass model, because a larger…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-01 Osamu Seto , Yo Toda

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

We study the generalized version of energy-momentum squared gravity (EMSG) in the Palatini formalism. This theory allows the existence of a scalar constructed with energy-momentum tensor as $T_{\alpha\beta}T^{\alpha\beta}$ in the generic…

General Relativity and Quantum Cosmology · Physics 2020-09-28 Elham Nazari , Farahnaz Sarvi , Mahmood Roshan

We perform a comprehensive investigation of the early-to-late time cosmic evolution within the framework of $f(Q,L_m)$ gravity, characterized by a non-minimal coupling between non-metricity and matter. The model is further tested against a…

General Relativity and Quantum Cosmology · Physics 2026-04-28 Rajdeep Mazumdar , Kalyan Malakar , Kalyan Bhuyan

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

Big Bang Nucleosynthesis (BBN) is very sensitive to the cosmological expansion rate. If the gravitational constant $G$ took a different value during the nucleosynthesis epoch than today, the primordial abundances of light elements would be…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-18 James Alvey , Nashwan Sabti , Miguel Escudero , Malcolm Fairbairn

We use BBN observational data on primordial abundance of ${}^4He$ to constrain f(T) gravity. The three most studied viable $f(T)$ models, namely the power law, the exponential and the square-root exponential are considered, and the BBN…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-20 S. Capozziello , G. Lambiase , E. N. Saridakis

We present a multi-epoch test of f(T) gravity with nonminimal torsion-matter coupling, combining early- and late-Universe observations. At the MeV scale, Big-Bang Nucleosynthesis constrains the fractional variation of the weak freeze-out…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-27 Yahia Al-Omar , Majida Nahili , Nidal Chamoun
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