Results 21 to 30 of about 79,313 (303)
On the Conformal Frames in f(R) Gravity
Universe, 2022 We discuss gravitational physics in the Jordan and Einstein frames of f(R) gravity coupled to the Standard Model. We elucidate the way in which the observed gravitational coupling arises in the Einstein frame for generic f(R).
Yuri Shtanov
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Big Bang Nucleosynthesis Constraints on f (T, TG) Gravity
Universe, 2022 We confront f(T,TG) gravity, with big bang nucleosynthesis (BBN) requirements. The former is obtained using both the torsion scalar, as well as the teleparallel equivalent of the Gauss–Bonnet term, in the Lagrangian, resulting to modified Friedmann ...
Petros Asimakis +3 more
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Testing Screened Modified Gravity
Universe, 2021 Long range scalar fields with a coupling to matter appear to violate known bounds on gravitation in the solar system and the laboratory. This is evaded thanks to screening mechanisms.
Philippe Brax +3 more
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Mathematics, 2023 In this work, it is shown that the geometry of a gravity field generated by a spheroid with low eccentricity can be described with the help of a newly modified Helmholtz equation.
Gerassimos Manoussakis
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Modified gravity tomography [PDF]
Physics Letters B, 2012 7 pages, 1 figure, minor ...
Brax, P., Davis, A.-C., Li, B.
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Non-conserved modified gravity theory
European Physical Journal C: Particles and Fields, 2023 In the curved spacetime the conservation of stress-energy tensor $${\mathcal {T}}_{\,\,\,\,\, \mu ;\nu }^{\nu }=0$$ T μ ; ν ν = 0 has been questioned by Rastall. However, this idea in which $${\mathcal {T}}_{\,\,\,\,\, \mu ;\nu }^{\nu }=\lambda R_{,\mu }$
H. R. Fazlollahi
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Modified gravity and the CMB [PDF]
Physical Review D, 2012 15 pages, 10 figures, published ...
Brax, Philippe, Davis, Anne-Christine
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Perturbations of Spinning Black Holes beyond General Relativity: Modified Teukolsky Equation
Physical Review X, 2023 The detection of gravitational waves from compact binary mergers by the LIGO/Virgo Collaboration has, for the first time, allowed for tests of relativistic gravity in the strong, dynamical, and nonlinear regime.
Dongjun Li +3 more
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THERMODYNAMICS IN MODIFIED GRAVITY THEORIES [PDF]
International Journal of Modern Physics D, 2011 We demonstrate that there exists an equilibrium description of thermodynamics on the apparent horizon in the expanding cosmological background for a wide class of modified gravity theories with the Lagrangian density f(R,ϕ,X), where R is the Ricci scalar and X is the kinetic energy of a scalar field ϕ.
Bamba, Kazuharu +2 more
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Nonderivative modified gravity: a classification [PDF]
Journal of Cosmology and Astroparticle Physics, 2014 No ...
Comelli D, Nesti F, PILO, LUIGI
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