Results 21 to 30 of about 68,602 (263)
Limited modified gravity [PDF]
Journal of Cosmology and Astroparticle Physics, 2020 We systematically assess several limiting cases of modified gravity, where particular theoretical or observational conditions hold. This framework includes the well known scalar-tensor gravity and No Slip Gravity and No Run Gravity, and we extend it to three new limits: Only Run, Only Light, and Only Growth Gravities.
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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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Nonderivative modified gravity: a classification [PDF]
Journal of Cosmology and Astroparticle Physics, 2014 No ...
Comelli D, Nesti F, PILO, LUIGI
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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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International Journal of Modern Physics D, 2008 We describe how a certain simple modification of general relativity, in which the local cosmological constant is allowed to depend on the space–time curvature, predicts the existence of halos of modified gravity surrounding spherically symmetric objects. We show that the gravitational mass of an object weighed together with its halo can be much larger
Krasnov, Kirill, Shtanov, Yuri
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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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Asymptotically flat vacuum solution for a rotating black hole in a modified gravity theory
European Physical Journal C: Particles and Fields, 2022 The theory of f(R)-gravity is one of the theories of modified Einstein gravity. The vacuum solution, on the other hand, of the field equation is the solution for black hole geometry.
Arghya Ranjan Das +1 more
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Stability in generalized Modified Gravity [PDF]
AIP Conference Proceedings, 2009 The stability issue of a large class of modified gravitational models is discussed with particular emphasis to de Sitter solutions. Three approaches are briefly presented and the generalization to more general cases is mentioned.
S. Zerbini, Shaaban Khalil
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HOLOGRAPHIC MODIFIED GRAVITY [PDF]
International Journal of Modern Physics D, 2008 In this paper, we investigate cosmological application of holographic dark energy density in the modified gravity framework. We employ the holographic model of dark energy to obtain the equation of state for the holographic energy density in a spatially flat universe. Our calculation shows that, taking ΩΛ = 0.73 for the present time, it is possible to
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Critical gravity in the Chern–Simons modified gravity [PDF]
The European Physical Journal C, 2011 13 pages, 1 figure, version to appear in ...
Moon, Taeyoon, Myung, Yun Soo
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