Results 11 to 20 of about 1,881,508 (108)
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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PhD thesis : Compact objects in modified theories of gravity [PDF]
The formulation of General Relativity by Albert Einstein in 1915 revolutionised our understanding of the gravitational interaction. However, despite its tremendous successes, this theory struggle to explain certain important phenomena such as the ...
Ducobu, Ludovic
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HOLOGRAPHIC MODIFIED GRAVITY [PDF]
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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Stability in generalized Modified Gravity [PDF]
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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Testing Modified Gravity with the Sunyaev Zel'dovich Effect [PDF]
): In this thesis, we present a method to test modified-gravity models. Growth of large-scale structures is directly related to the governing gravity theory.
Upadhyay, Vikram
core
The observable universe could be a 1+3-surface (the “brane”) embedded in a 1+3+d-dimensional spacetime (the “bulk”), with Standard Model particles and fields trapped on the brane while gravity is free to access the bulk.
Roy Maartens +3 more
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ON EXPONENTIAL MODIFIED GRAVITY [PDF]
A modified theory of gravity with the function F(R) = R exp (αR) instead of Ricci scalar R in the Einstein–Hilbert action is considered and analyzed. The action of the model is converted into Einstein–Hilbert action at small value of the parameter α. From local tests we obtain a bound on the parameter α ≤ 10-6 cm 2.
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Critical gravity in the Chern–Simons modified gravity [PDF]
13 pages, 1 figure, version to appear in ...
Moon, Taeyoon, Myung, Yun Soo
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Early modified gravity: Implications for cosmology [PDF]
We study the effects of modifications of gravity after Big Bang Nucleosynthesis (BBN) which would manifest themselves mainly before recombination. We consider their effects on the Cosmic Microwave Background (CMB) radiation and on the formation of large scale structure.
Brax, Philippe +4 more
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added references; made some clarifications; 8 ...
Dimitrijevic, Ivan +3 more
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