Results 11 to 20 of about 1,984,506 (249)
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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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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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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A new approach and code for spinning black holes in modified gravity [PDF]
, 2023 We discuss and implement a spectral method approach to computing stationary and axisymmetric black hole solutions and their properties in modified theories of gravity.
David J Mulryne +5 more
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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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Modified gravity: A unified approach [PDF]
Physical Review D, 2021 Starting from the original Einstein action, sometimes called the Gamma squared action, we propose a new setup to formulate modified theories of gravity. This can yield a theory with second order field equations similar to those found in other popular modified gravity models. Using a more general setting the theory gives fourth order equations.
Christian G. Böhmer, Erik Jensko
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Modified Theories of Gravity and Cosmological Applications [PDF]
, 2023 This reprint focuses on recent aspects of gravitational theory and cosmology. It contains subjects of particular interest for modified gravity theories and applications to cosmology, special attention is given to Einstein–Gauss–Bonnet, f(R)-gravity ...
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