Results 21 to 30 of about 115,585,122 (266)
PhD thesis : Compact objects in modified theories of gravity [PDF]
, 2022 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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f(G) modified gravity and the energy conditions
Journal of Physics: Conference Series, 2011 Motivated by string/M-theory predictions that scalar field couplings with the Gauss-Bonnet invariant, G, are essential in the appearance of non-singular early time cosmologies, we discuss the viability of an interesting alternative gravitational theory, namely, modified Gauss-Bonnet gravity, and present the viability bounds arising from the energy ...
García, Nadiezhda Montelongo +3 more
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, 2010 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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Quasi-cosmological traversable wormholes in f(R) gravity
European Physical Journal C: Particles and Fields, 2019 In this paper, we study traversable wormholes in the context of f(R) gravity. Exact solutions of traversable wormholes are found by imposing the nonconstant Ricci scalar. These solutions asymptotically match spherical, flat and hyperbolic FRW metric.
Hanif Golchin, Mohammad Reza Mehdizadeh
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THEORY OF GRAVITY "ENERGY-WAVE": THE ORIGIN [PDF]
, 2014 In this paper I derive an equation relating the gravitational acceleration with the gravitational wavelength corresponding to the “gravitational energy” density at a point in space and with the speed of light, without using the gravitational constant of ...
Rodolfo Sergio González Castro +1 more
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European Physical Journal C: Particles and Fields, 2021 This study is devoted to explore the physical aspects of wormhole geometry under embedded class-1 spacetime in $$f(T,\tau )$$ f ( T , τ ) gravity, where $$\tau $$ τ denotes the trace of the energy-momentum tensor and T is the torsion.
Allah Ditta +4 more
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Energy Conditions in Palatini Approach to Modified $f(R)$ Gravity
Journal of High Energy Physics, Gravitation and Cosmology, 2018 In this paper, we review modified $f(R)$ theories of gravity in Palatini formalism. In this framework, , we use the Raychaudhuri's equation along with the requirement that the gravity is attractive, which holds for any geometrical theory of gravity to discuss the energy conditions. Then, to derive these conditions, we obtain an expression for effective
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Anisotropic Quintessence Strange Stars in f(T) Gravity with Modified Chaplygin Gas
Advances in High Energy Physics, 2018 In this paper, we study the existence of strange star in the background of f(T) modified gravity where T is a scalar torsion. In KB metric space, we derive the equations of motion using anisotropic property within the spherically strange star with ...
Pameli Saha, Ujjal Debnath
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European Physical Journal C: Particles and Fields, 2019 In this work, we get an idea of the existence of compact stars in the background of f(T) modified gravity where T is a scalar torsion. We acquire the equations of motion using anisotropic property within the spherically compact star with electromagnetic ...
Pameli Saha, Ujjal Debnath
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Irreversible Geometrothermodynamics of Open Systems in Modified Gravity
Entropy, 2023 In this work, we explore the formalism of the irreversible thermodynamics of open systems and the possibility of gravitationally generated particle production in modified gravity.
Miguel A. S. Pinto +2 more
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