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Reconstructing Modified and Alternative Theories of Gravity
Universe, 2023 A viable radiation-dominated era in the early universe is best described by the standard (FLRW) model of cosmology. In this short review, we demonstrate reconstruction of the forms of F(R) in the modified theory of gravity and the metric compatible F(T ...
Dalia Saha +2 more
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Post-Minkowskian Hamiltonians in modified theories of gravity
Physics Letters B, 2020 The aim of this note is to describe the computation of post-Minkowskian Hamiltonians in modified theories of gravity. Exploiting a recent relation between scattering amplitudes of massive scalars and potentials for relativistic point-particles we derive ...
Andrea Cristofoli
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Generalized disformal invariance of cosmological perturbations with second-order field derivatives
Physics Letters B, 2021 We investigate how the comoving curvature and tensor perturbations are transformed under the generalized disformal transformation with the second-order covariant derivatives of the scalar field, where the free functions depend on the fundamental elements
Masato Minamitsuji
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Universe, 2022 Scalar Tensor Vector Gravity (STVG) or MOdified Gravity (MOG) is a metric theory of gravity with dynamical scalar fields and a massive vector field introduced in addition to the metric tensor.
Sreekanth Harikumar
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Living Reviews in Relativity, 2014 We review recent progress in massive gravity. We start by showing how different theories of massive gravity emerge from a higher-dimensional theory of general relativity, leading to the Dvali–Gabadadze–Porrati model (DGP), cascading gravity, and ghost ...
Claudia de Rham
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Exact rotating black hole solutions for f(R) gravity by modified Newman Janis algorithm
European Physical Journal C: Particles and Fields, 2023 We show that the f(R)-gravity theories with constant Ricci scalar in the Jordan/Einstein frame can be described by Einstein or Einstein–Maxwell gravity with a cosmological term and a modified gravitational constant.
Pankaj Chaturvedi +3 more
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The validity of Birkhoff’s theorem in modified teleparallel equivalent theories of gravity
European Physical Journal C: Particles and Fields, 2023 Birkhoff’s theorem is a vitally important theorem in studying local systems in theories of gravity. In this paper we provide a straightforward proof of the validity of Birkhoff’s theorem in modified teleparallel equivalent theories of gravity, which ...
Ji-Yu Cheng
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Disformal transformation of cosmological perturbations
Physics Letters B, 2014 We investigate the gauge-invariant cosmological perturbations in the gravity and matter frames in the general scalar–tensor theory where two frames are related by the disformal transformation.
Masato Minamitsuji
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General Relativity solutions in modified gravity
Physics Letters B, 2018 Recent gravitational wave observations of binary black hole mergers and a binary neutron star merger by LIGO and Virgo Collaborations associated with its optical counterpart constrain deviation from General Relativity (GR) both on strong-field regime and
Hayato Motohashi, Masato Minamitsuji
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Probing the existence of the ZTF Casimir wormholes in the framework of f(R) gravity
Nuclear 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
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