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Related papers: Emergent modified gravity coupled to scalar matter

200 papers

We argue that a field theory defined on noncommutative (NC) spacetime should be regarded as a theory of gravity, which we refer to as the emergent gravity. A whole point of the emergent gravity is essentially originated from the basic…

High Energy Physics - Theory · Physics 2009-11-13 Hyun Seok Yang

It has been suggested that Einstein's theory of General Relativity can be modified to accomodate mismatches between the gravitational field and luminous matter on a wide range of scales. Covariant theories of modified gravity generically…

Astrophysics · Physics 2009-03-31 P. G Ferreira , C. Skordis , C. Zunckel

In this thesis, we study the implications of Quantum Gravity models for the dynamics of spacetime and the ensuing departures from classical General Relativity. The main focus is on cosmological applications, particularly the impact of…

General Relativity and Quantum Cosmology · Physics 2018-04-09 Marco de Cesare

An exponential modified gravity with additional logarithmic corrections is considered with the presence of an axion-like scalar field in the role of dark matter. Axion fields are thought to become important at late-times when the axion-like…

General Relativity and Quantum Cosmology · Physics 2024-06-14 Sergei D. Odintsov , Diego Sáez-Chillón Gómez , German S. Sharov

In physical theories where the energy (action) is localized near a submanifold of a constant curvature space, there is a universal expression for the energy (or the action). We derive a multipole expansion for the energy that has a finite…

High Energy Physics - Theory · Physics 2017-03-10 Orlando Alvarez , Matthew Haddad

Our conventional system of physical units is based on local or microscopic {\it dimensional} quantities which are {\it defined}, for convenience or otherwise aesthetic reasons, to be spacetime-independent. A more general choice of units may…

General Physics · Physics 2013-08-06 Meir Shimon

We analyze the phase space of gravity non-minimally coupled to a scalar field in a generic local Lorentz frame. We reduce the set of constraints to a first-class one by fixing a specific hypersurfaces in the phase space. The main issue of…

General Relativity and Quantum Cosmology · Physics 2013-05-29 F. Cianfrani , G. Montani

We review a novel and authentic way to quantize gravity. This novel approach is based on the fact that Einstein gravity can be formulated in terms of a symplectic geometry rather than a Riemannian geometry in the context of emergent…

High Energy Physics - Theory · Physics 2014-12-30 Jungjai Lee , Hyun Seok Yang

In order to bypass the big bang singularity, we develop an emergent universe scenario within a covariant extension of General Relativity known as \emph{"Energy-Momentum Squared Gravity"}. The extra terms of the model emerge in the high…

General Relativity and Quantum Cosmology · Physics 2022-04-05 Mohsen Khodadi , Alireza Allahyari , Salvatore Capozziello

In the present work, we review some general aspects of modified gravity theories, investigating mathematical and physical properties and, more specifically, the feature of viable and realistic models able to reproduce the dark energy epoch…

General Relativity and Quantum Cosmology · Physics 2013-10-16 Ratbay Myrzakulov , Lorenzo Sebastiani , Sergio Zerbini

We investigate a non-minimally coupled scalar field theory within the framework of scalar-tensor gravity formulated in non-metricity geometry, focusing on spatially curved FLRW spacetimes. Employing the dynamical systems approach with…

General Relativity and Quantum Cosmology · Physics 2025-09-03 Ghulam Murtaza , Avik De , Andronikos Paliathanasis

Based on the scalar-tensor-vector modified gravitational theory, a modified gravity Schwarzschild black hole solution has been given in the existing literature. Such a black hole spacetime is obtained through the inclusion of a modified…

General Relativity and Quantum Cosmology · Physics 2022-06-10 Daqi Yang , Wenfu Cao , Naying Zhou , Hongxing Zhang , Wenfang Liu , Xin Wu

We extend the thermodynamic derivation of gravity in the Jacobson framework by generalizing the Clausius relation through a nontrivial entropy functional. We show that entropy deformations appear as modifications of the effective…

General Relativity and Quantum Cosmology · Physics 2026-04-14 H. R. Fazlollahi

A model for quantized gravity coupled to matter in the form of a single scalar field is investigated in four dimensions. For the metric degrees of freedom we employ Regge's simplicial discretization, with the scalar fields defined at the…

High Energy Physics - Theory · Physics 2009-10-22 Herbert W. Hamber , Ruth M. Williams

A new conception is proposed in Ref.\cite{Verlinde:2010hp,Padmanabhan:2009kr} that gravity is one kind of entropic force. In this letter, we try to discuss its applications to the modified gravities by using three different corrections to…

High Energy Physics - Theory · Physics 2011-08-05 Yi Zhang , Yun-gui Gong , Zong-Hong Zhu

In this work, we study cosmological and astrophysical applications of the recently proposed generalized hybrid metric-Palatini gravity theory, which combines features of both the metric and the Palatini approaches to the variational method…

General Relativity and Quantum Cosmology · Physics 2019-11-20 João Luís Rosa

Quantum gravity is expected to be necessary in order to understand situations where classical general relativity breaks down. In particular in cosmology one has to deal with initial singularities, i.e. the fact that the backward evolution…

General Relativity and Quantum Cosmology · Physics 2016-10-19 Martin Bojowald

Modified gravity theories have received increased attention lately due to combined motivation coming from high-energy physics, cosmology and astrophysics. Among numerous alternatives to Einstein's theory of gravity, theories which include…

General Relativity and Quantum Cosmology · Physics 2014-11-18 Thomas P. Sotiriou , Valerio Faraoni

Over the past century, General Relativity (GR) has been a cornerstone of gravitational theory. However, recent cosmological observations, such as the accelerated expansion of the Universe, challenge its completeness and the standard…

General Relativity and Quantum Cosmology · Physics 2025-06-02 Lakhan V. Jaybhaye

Spherically symmetric models of loop quantum gravity have been studied recently by different methods that aim to deal with structure functions in the usual constraint algebra of gravitational systems. As noticed by Gambini and Pullin, a…

General Relativity and Quantum Cosmology · Physics 2015-09-09 Martin Bojowald , Suddhasattwa Brahma , Juan D. Reyes