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We study teleparallel gravitational theories with are invariant under the conformal transformations. Wide family of the gravitational Lagrangians that are invariant under conformal transformations have investigated. Cosmological solutions…

General Relativity and Quantum Cosmology · Physics 2014-06-24 Davood Momeni , Ratbay Myrzakulov

Within the general framework of $f(R)$ gravity, we introduce a function of the electromagnetic curvature invariant $f(\mathbb{F})$ that couples minimally to gravitation to ensure a consistent treatment of curvature functions in these…

General Relativity and Quantum Cosmology · Physics 2026-03-19 Francesco Bajardi , Micol Benetti , Salvatore Capozziello , Abedennour Dib

An alternative to dark energy as an explanation for the present phase of accelerated expansion of the Universe is that the Friedmann equation is modified, e.g. by extra dimensional gravity, on large scales. We explore a natural…

Astrophysics · Physics 2009-11-10 Oystein Elgaroy , Tuomas Multamaki

Conformal transformation as a mathematical tool has been used in many areas of gravitational physics. In this paper, we would consider the gravity's rainbow, in which the metric could be treated as a conformal rescaling of the original…

General Relativity and Quantum Cosmology · Physics 2018-02-21 Miao He , Ping Li , Zi-Liang Wang , Jia-Cheng Ding , Jian-Bo Deng

We introduce the Brans-Dick de Rham-Gabadadze-Tolley massive gravity theory which is the new extension of nonlinear massive gravity. We demonstrate a detailed study of the cosmological properties of this theory of gravity, and we show the…

General Relativity and Quantum Cosmology · Physics 2022-06-17 Sobhan Kazempour , Amin Rezaei Akbarieh

Conformal symmetries appear in many parts of physics and play a unique role in exploring the Universe. In this work, we consider the possibility of constructing conformal theories of gravity in the Symmetric Teleparallel Gravity framework,…

General Relativity and Quantum Cosmology · Physics 2020-03-18 Viktor Gakis , Martin Krššák , Jackson Levi Said , Emmanuel N. Saridakis

We show that modelling the universe as a pre-geometric system with emergent quantum modes, and then constructing the classical limit, we obtain a new account of space and gravity that goes beyond Newtonian gravity even in the…

General Physics · Physics 2007-09-20 Reginald T Cahill

In the covariant averaging scheme of macroscopic gravity, the process of averaging breaks the metricity of geometry. We reinterpret the back-reaction within macroscopic gravity in terms of the non-metricity of averaged geometry. This…

General Relativity and Quantum Cosmology · Physics 2024-06-18 Anish Agashe , Sai Madhav Modumudi

In this paper, we discuss the leading order correction to the equation of motion of the particle, which presumably describes the effect of gravitational radiation reaction. We derive the equation of motion in two different ways. The first…

General Relativity and Quantum Cosmology · Physics 2009-10-09 Yasushi Mino , Misao Sasaki , Takahiro Tanaka

We consider linear perturbation equations for long-wavelength scalar metric perturbations in generalised gravity, applicable to non-singular cosmological models including a bounce from collapse to expansion in the very early universe. We…

High Energy Physics - Theory · Physics 2008-11-26 Antonio Cardoso , David Wands

The alternative dynamics of loop quantum cosmology is examined by the path integral formulation. We consider the spatially flat FRW models with a massless scalar field, where the alternative quantization inherit more features from full loop…

General Relativity and Quantum Cosmology · Physics 2015-06-05 Li Qin , Guo Deng , Yongge Ma

Conformal geometry is considered within a general relativistic framework. An invariant distant for proper time is defined and a parallel displacement is applied in the distorted space-time, modifying Einstein's equation appropriately. A…

General Relativity and Quantum Cosmology · Physics 2015-06-16 Edmund A. Chadwick , Timothy F. Hodgkinson , Graham S. McDonald

Employing the non-additive Tsallis entropy, $S\sim A^{\beta}$, for the large-scale gravitational systems, we disclose that in the cosmological scales both Friedmann equation and the equation of motion for the Newtonian cosmology get…

General Physics · Physics 2020-01-22 Ahmad Sheykhi

We derive the equations of motion of extended deformable bodies in metric-affine gravity. The conservation laws which follow from the invariance of the action under the general coordinate transformations are used as a starting point for the…

General Relativity and Quantum Cosmology · Physics 2014-10-22 Dirk Puetzfeld , Yuri N. Obukhov

It is shown that, with some reasonable assumptions, the theory of general relativity can be made compatible with quantum mechanics by using the field equations of general relativity to construct a Robertson-Walker metric for a quantum…

High Energy Physics - Theory · Physics 2007-05-23 Vu B Ho

Cosmology in extended theories of gravity is considered assuming the Palatini variational principle, for which the metric and connection are independent variables. The field equations are derived to linear order in perturbations about the…

Astrophysics · Physics 2015-06-24 Tomi Koivisto , Hannu Kurki-Suonio

We study a $R^{2}$ model of gravity with torsion in a closed Friedmann-Robertson-Walker universe. The model is cast in Hamiltonian form subtracting from the original Lagrangian the total time derivative of $f_{K}f_{R}$, where $f_{K}$ is…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Giampiero Esposito

Bohmian mechanics is a nonlocal hidden-variable interpretation of quantum theory which predicts that particles follow deterministic trajectories in spacetime. Historically, the study of Bohmian trajectories has mainly been restricted to…

Quantum Physics · Physics 2022-07-19 Joshua Foo , Estelle Asmodelle , Austin P. Lund , Timothy C. Ralph

The 1+3 covariant approach and the covariant gauge-invariant approach to perturbations are used to analyze in depth conformal transformations in cosmology. Such techniques allow us to obtain very interesting insights on the physical content…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Sante Carloni , Emilio Elizalde , Sergei Odintsov

We develop the general theory of spinning particles with electric and magnetic dipole moments moving in arbitrary electromagnetic, inertial and gravitational fields. Both the quantum-mechanical and classical dynamics is investigated. We…

High Energy Physics - Theory · Physics 2017-11-15 Yuri N. Obukhov , Alexander J. Silenko , Oleg V. Teryaev
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