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Constraining Modified Gravity with Euclid [PDF]

open access: yes, 2010
Future proposed satellite missions as Euclid can offer the opportunity to test general relativity on cosmic scales through mapping of the galaxy weak lensing signal. In this paper we forecast the ability of these experiments to constrain modified gravity
A. R. Cooray   +8 more
core   +2 more sources

Chaos in a Magnetized Modified Gravity Schwarzschild Spacetime

open access: yesUniverse, 2022
Based on the scalar–tensor–vector modified gravitational theory, a modified gravity Schwarzschild black hole solution has been given in the existing literature.
Daqi Yang   +5 more
doaj   +1 more source

Viscosity in Modified Gravity [PDF]

open access: yesEntropy, 2012
A bulk viscosity is introduced in the formalism of modified gravity. It is shownthat, based on a natural scaling law for the viscosity, a simple solution can be found forquantities such as the Hubble parameter and the energy density. These solutions mayincorporate a viscosity-induced Big Rip singularity.
openaire   +4 more sources

Non-singular modified gravity: the unification of the inflation, dark energy and dark mater [PDF]

open access: yes, 2009
Using the fluid representation, we formulate the conditions for the appearance of all four types finite-time future singularity in modified gravity in accelerating FRW universe.
Nojiri, Shin'ichi, Odintsov, Sergei D.
core   +2 more sources

Modified gravity and cosmology

open access: yesPhysics Reports, 2012
In this review we present a thoroughly comprehensive survey of recent work on modified theories of gravity and their cosmological consequences. Amongst other things, we cover General Relativity, Scalar-Tensor, Einstein-Aether, and Bimetric theories, as well as TeVeS, f(R), general higher-order theories, Horava-Lifschitz gravity, Galileons, Ghost ...
Clifton, T.   +7 more
openaire   +5 more sources

Cosmological bound from the neutron star merger GW170817 in scalar–tensor and F(R) gravity theories

open access: yesPhysics Letters B, 2018
We consider the evolution of cosmological gravitational waves in scalar–tensor theory and F(R) gravity theory as typical models of the modified gravity. Although the propagation speed is not changed from the speed of light, the propagation phase changes ...
Shin'ichi Nojiri, Sergei D. Odintsov
doaj   +1 more source

Causal hierarchy in modified gravity

open access: yesJournal of High Energy Physics, 2020
We investigate the causal hierarchy in various modified theories of gravity. In general relativity the standard causal hierarchy, (key elements of which are chronology, causality, strong causality, stable causality, and global hyperbolicity), is well ...
Raúl Carballo-Rubio   +3 more
doaj   +1 more source

Probing the existence of the ZTF Casimir wormholes in the framework of f(R) gravity

open access: yesNuclear Physics B, 2022
For the spherically symmetric static traversable wormholes, supported by the Casimir energy in f(R)=R+αR2 Quadratic, f(R)=f0Rn power-law Modified Gravity (MOG) theories we investigate energy conditions and dynamical stability of the wormhole solutions ...
Oleksii Sokoliuk   +2 more
doaj   +1 more source

Formalizing anisotropic inflation in modified gravity

open access: yesNuclear Physics B, 2022
Motivated by the fact that the pre-inflationary era may evolve in an exotic way, in this work we formalize anisotropic evolution in the context of modified gravity, focusing on pre-inflationary and near the vicinity of the inflationary epochs.
S. Nojiri   +3 more
doaj   +1 more source

Modified gravity and coupled quintessence

open access: yes, 2014
The distinction between modified gravity and quintessence or dynamical dark energy is difficult. Many models of modified gravity are equivalent to models of coupled quintessence by virtue of variable transformations.
Wetterich, C.
core   +1 more source

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