English
Related papers

Related papers: Scalar-tensor gravity and conformal continuations

200 papers

We provide the correspondence between the variables in the Jordan frame and those in the Einstein frame in scalar-tensor gravity and consider the frame-(in)dependence of the cosmological observables. In particular, we show that the…

General Relativity and Quantum Cosmology · Physics 2015-06-16 Takeshi Chiba , Masahide Yamaguchi

Symmetric teleparallel gravity (STG) is a gravity theory which takes non-metricity tensor to describe gravity effects. In the STG framework, we study the conformal equivalent scalar-tensor theory of f(Q) model and calculate the cosmological…

General Relativity and Quantum Cosmology · Physics 2024-04-26 Dehao Zhao

We consider ${\cal N}=4$ conformal supergravity with an arbitrary holomorphic function of the complex scalar $S$ which parametrizes the $SU(1,1)/U(1)$ coset. Assuming non-vanishings vevs for $S$ and the scalars in a symmetric matrix…

High Energy Physics - Theory · Physics 2021-10-12 Ioannis Dalianis , Alex Kehagias , Ioannis Taskas , George Tringas

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 analyze a class of topological static spherically symmetric vacuum solutions in $f(Q)$-gravity. We considered an Ansatz ensuring that those solutions trivially satisfy the field equations of the theory when the non-metricity scalar is…

General Relativity and Quantum Cosmology · Physics 2023-09-14 Marco Calzá , Lorenzo Sebastiani

We consider tensor-vector theories with varying the space-time-matter coupling constant (varying Einstein velocity) in a spatially flat FRW universe. We examine the dynamics of this model by dynamical system method assuming a \Lambda CDM…

General Physics · Physics 2015-06-11 Azam Izadi , Ali Shojai , Mojtaba Nouradini

We show that there are 2 equivalent first order descriptions of 2+1 gravity with non-zero cosmological constant. One is the well-known spacetime description and the other is in terms of evolving conformal geometry. The key tool that links…

General Relativity and Quantum Cosmology · Physics 2013-03-27 Sean Gryb , Flavio Mercati

The effective dynamics of scalar-tensor theory (STT) in the Jordan frame is studied in the context of loop quantum cosmology with holonomy corrections. After deriving the effective Hamiltonian from the connection dynamics formulation, we…

General Relativity and Quantum Cosmology · Physics 2020-01-01 Yu Han

We revisit the static spherically symmetric solutions of Einstein's General Relativity with a conformally coupled scalar field in arbitrary dimensions. Using a four rank tensor introduced earlier we recast the field equations in a…

General Relativity and Quantum Cosmology · Physics 2024-12-17 Sourya Ray

We consider Friedmann-Lema\^{\i}tre-Robertson-Walker flat cosmological models in the framework of general Jordan frame scalar-tensor theories of gravity with arbitrary coupling function and potential. For the era when the cosmological…

General Relativity and Quantum Cosmology · Physics 2011-01-06 Laur Järv , Piret Kuusk , Margus Saal

The response of a gravitational wave detector to scalar waves is analysed in the framework of the debate on the choice of conformal frames for scalar-tensor theories. A correction to the geodesic equation arising in the Einstein conformal…

High Energy Physics - Theory · Physics 2009-11-07 S. Bellucci , V. Faraoni , D. Babusci

We present arguments for the existence of both globally regular and black hole solutions of the Einstein equations with a conformally coupled scalar field, in the presence of a negative cosmological constant, for space-time dimensions…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Eugen Radu , Elizabeth Winstanley

We describe the dynamics of a cosmological term in the spherically symmetric case by an r-dependent second rank symmetric tensor \Lambda_{\mu\nu} invariant under boosts in the radial direction. The cosmological tensor \Lambda_{\mu\nu}…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Irina Dymnikova

In this work, we analyse static spherically symmetric solutions in the framework of mimetic gravity, an extension of general relativity where the conformal degree of freedom of gravity is isolated in a covariant fashion. Here we extend…

General Relativity and Quantum Cosmology · Physics 2018-12-13 Ratbay Myrzakulov , Lorenzo Sebastiani , Sunny Vagnozzi , Sergio Zerbini

We present a new class of solutions for static spherically symmetric wormhole spacetimes in conformal gravity and outline a detailed method for their construction. As an explicit example, we construct a class of traversable and…

General Relativity and Quantum Cosmology · Physics 2018-10-09 Manuel Hohmann , Christian Pfeifer , Martti Raidal , Hardi Veermäe

We show that Schwarzschild geometry remains as a vacuum solution for those four-dimensional f(T) gravitational theories behaving as ultraviolet deformations of general relativity. In the gentler context of three-dimensional gravity, we also…

General Relativity and Quantum Cosmology · Physics 2015-05-30 Rafael Ferraro , Franco Fiorini

A new class of solutions of the Einstein field equations in spherical symmetry is found. The new solutions are mathematically described as the metrics admitting separation of variables in area-radius coordinates. Physically, they describe…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Roberto Giambo' , Fabio Giannoni , Giulio Magli , Paolo Piccione

In this thesis we analyze a very simple model of two dimensional quantum gravity based on causal dynamical triangulations (CDT). We present an exactly solvable model which indicates that it is possible to incorporate spatial topology…

High Energy Physics - Theory · Physics 2008-10-07 Willem Westra

We describe the general structure of the spherically symmetric solutions in the Weyl conformal gravity. The corresponding Bach equations are derived for the special type of metrics, which can be considered as the representative of the…

General Relativity and Quantum Cosmology · Physics 2016-04-21 V. A. Berezin , V. I. Dokuchaev , Yu. N. Eroshenko

We consider the most cosmologically interesting and relevant case of scalar-tensor theory (STT) and derive new normal and phantom, dynamical and static, solutions. We determine the Bianchi I Kasner exponents and show that the dynamical…

General Relativity and Quantum Cosmology · Physics 2020-07-23 Mustapha Azreg-Aïnou
‹ Prev 1 4 5 6 7 8 10 Next ›