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Related papers: On singularity-resolution in mimetic gravity

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We show that the f(T) gravitational paradigm, in which gravity is described by an arbitrary function of the torsion scalar, can provide a mechanism for realizing bouncing cosmologies, thereby avoiding the Big Bang singularity. After…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-07 Yi-Fu Cai , Shih-Hung Chen , James B. Dent , Sourish Dutta , Emmanuel N. Saridakis

We investigate a bounce realization in the framework of higher order curvature in $ f(R,T) $ modified theory of gravity. We perform a detailed analysis of the cosmological parameters to explain the contraction phase, the bounce phase, and…

General Relativity and Quantum Cosmology · Physics 2023-07-19 J. K. Singh , Shaily , Akanksha Singh , Aroonkumar Beesham , Hamid Shabani

Although there is general agreement that a removal of classical gravitational singularities is not only a crucial conceptual test of any approach to quantum gravity but also a prerequisite for any fundamental theory, the precise criteria…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Martin Bojowald

Despite many nice properties and numerous achievements, general relativity is not a complete theory. One of actual approaches towards more complete theory of gravity is its nonlocal modification. We present here a brief review of nonlocal…

General Relativity and Quantum Cosmology · Physics 2017-01-04 Branko Dragovich

We present an effective theory to describe the quantization of spherically symmetric vacuum in loop quantum gravity. We include anomaly-free holonomy corrections through a canonical transformation of the Hamiltonian of general relativity,…

General Relativity and Quantum Cosmology · Physics 2023-04-18 Asier Alonso-Bardaji , David Brizuela , Raül Vera

We study spherical charged black holes in the presence of a cosmological constant with corrections motivated by the theory of loop quantum gravity. The effective theory is constructed at the Hamiltonian level by introducing certain…

General Relativity and Quantum Cosmology · Physics 2023-04-12 Asier Alonso-Bardaji , David Brizuela , Raül Vera

In this work, following our recent findings in [1], we extend our analysis to explore the generalization of spherically symmetric and static black-bounce solutions, known from General Relativity, within the framework of the $f(R)$ theory in…

General Relativity and Quantum Cosmology · Physics 2025-12-19 Marcos V. de S. Silva , T. M. Crispim , G. Alencar , R. R. Landim , Manuel E. Rodrigues

In this paper we study consistent solutions of spherically symmetric space in metric f(R) gravity theory. Here we inversely obtain a generic action from metric solutions that describe flat rotation curves in spiral galaxies without dark…

General Relativity and Quantum Cosmology · Physics 2021-05-11 Solmaz Asgari , Reza Saffari

New corrections to General Relativity are considered in the context of modified $f(R)$ gravity, that satisfy cosmological and local gravity constraints. The proposed models behave asymptotically as $R-2\Lambda$ at large curvature and show…

General Relativity and Quantum Cosmology · Physics 2022-01-13 L. N. Granda

The idea of "asymptotically free" gravity is implemented using a constrained mimetic scalar field. The effective gravitational constant is assumed to vanish at some limiting curvature. As a result singularities in contracting spatially flat…

High Energy Physics - Theory · Physics 2020-08-05 Ali H. Chamseddine , Viatcheslav Mukhanov , Tobias Russ

In Loop Quantum Gravity mathematically rigorous models of full quantum gravity were proposed. In this paper we study a cosmological sector of one of the models describing quantum gravity with positive cosmological constant coupled to…

General Relativity and Quantum Cosmology · Physics 2022-11-09 Marcin Kisielowski

The purpose of this work is to investigate the consequences of quantum gravity for the singularity problem. We study the higher-derivative terms that invariably appear in any quantum field theoretical model of gravity, handling them both…

High Energy Physics - Theory · Physics 2020-01-22 Iberê Kuntz , Roberto Casadio

In this study, the source of the black bounce is discussed in the context of $f(Q)$ theory. A body of research has been dedicated to the study of symmetric black bounce solutions that are generated by a combination of a scalar field with a…

General Relativity and Quantum Cosmology · Physics 2025-05-29 Pınar Kirezli , Doğukan Taşer

We consider modified $f(R)$ gravity with a kinetic curvature scalar as a chiral self-gravitating model in a spherically symmetric spacetime. Most attention devoted to finding solutions for special case of scaling transformation when…

General Relativity and Quantum Cosmology · Physics 2020-08-11 Sergey Chervon , Julio Fabris , Igor Fomin

In an attempt to re-establish space-time as an essential frame for formulating quantum gravity - rather than an "emergent" one -, we find that exact invariance under scale transformations is an essential new ingredient for such a theory.…

General Relativity and Quantum Cosmology · Physics 2009-09-21 Gerard 't Hooft

We describe a non-perturbative approach to studying the gravitational collapse of a scalar field in spherical symmetry with quantum gravity corrections. Quantum effects are described by a phase space function that modifies the constraints…

General Relativity and Quantum Cosmology · Physics 2011-09-15 Andreas Kreienbuehl , Viqar Husain , Sanjeev S. Seahra

We develop the general scheme for modified $f(R)$ gravity reconstruction from any realistic FRW cosmology. We formulate several versions of modified gravity compatible with Solar System tests where the following sequence of cosmological…

High Energy Physics - Theory · Physics 2008-11-26 Shin'ichi Nojiri , Sergei D. Odintsov

Loop quantum gravity introduces strong non-perturbative modifications to the dynamical equations in the semi-classical regime, which are responsible for various novel effects, including resolution of the classical singularity in a Friedman…

High Energy Physics - Theory · Physics 2007-05-23 Martin Bojowald , Roy Maartens , Parampreet Singh

Along this review, we focus on the study of several properties of modified gravity theories, in particular on black-hole solutions and its comparison with those solutions in General Relativity, and on Friedmann-Lemaitre-Robertson-Walker…

General Relativity and Quantum Cosmology · Physics 2015-06-05 A. de la Cruz-Dombriz , D. Saez-Gomez

Aspects of the full theory of loop quantum gravity can be studied in a simpler context by reducing to symmetric models like cosmological ones. This leads to several applications where loop effects play a significant role when one is…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Martin Bojowald