Results 21 to 30 of about 24,685 (268)
Results in Physics, 2023 The focus of this research is to investigate conformal vector fields (CVFs) of Bianchi type I space–times in modified teleparallel gravity (MTG). In order to determine such vector fields, we make a classification of said space–times. As a result, we discover thirty-one distinct Bianchi type I classes in the MTG.
Shabeela Malik +5 more
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Impact of curvature based geometric constraints on F(R) theory
European Physical Journal C: Particles and Fields, 2022 Theories of gravity are fundamentally a relation between matter and the geometric structure of the underlying spacetime. So once we put some additional restrictions on the spacetime geometry, the theory of gravity is bound to get the impact, irrespective
Tee-How Loo +3 more
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Wormholes in viable $$f(R)$$ f ( R ) modified theories of gravity and weak energy condition [PDF]
The European Physical Journal C, 2015 In this work wormholes in viable $f(R)$ gravity models are analysed. We are interested in exact solutions for stress-energy tensor components depending on different shape and redshift functions. Several solutions of gravitational equations for different $f(R)$ models are examined.
Pavlovic, Petar, Sossich, Marko
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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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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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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
core
Energy conditions in f(P) gravity
, 2022 f(P) gravity is a novel extension of Einsteinian cubic gravity in which the Ricci scalar in the action is replaced by a function of the curvature invariant P which represents the contractions of the Riemann tensor at the cubic order [C.
Bhattacharjee, Snehasish
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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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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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A study of cylindrically symmetric solutions in $$f(R, \phi , X)$$ f ( R , ϕ , X ) theory of gravity
European Physical Journal C: Particles and Fields, 2022 In this article, we aim to investigate some cylindrically symmetric solutions in a very well known modified theory named as $$f(R, \phi , X)$$ f ( R , ϕ , X ) theory of gravity, where the terms R, $$\phi $$ ϕ and X are clarified as Ricci Scalar, scalar ...
Adnan Malik +3 more
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