Zobrazeno 1 - 10
of 17
pro vyhledávání: '"83F05, 83D05"'
We investigate cosmological perturbations of f(G) gravity in the presence of a scalar field. Using the 1 + 3 covariant formalism, we present the energy overdensity perturbation equations responsible for large scale structure formation. After applying
Externí odkaz:
http://arxiv.org/abs/2312.15183
The consideration of a 1 + 3 covariant approach to cold dark matter universe with no shear cosmological dust model with irrotational flows is developed in the context of f (G) gravity theory in the present study. This approach reveals the existence o
Externí odkaz:
http://arxiv.org/abs/2305.01331
Publikováno v:
International Journal of Geometric Methods in Modern Physics (2023)
The present research paper is an investigation of dark energy nature of logarithmic $f(R, T)$-gravity cosmology in a flat FLRW space-time universe. We have derived modified Einstein's field equations for the function $f(R, T)=R-16\pi G\alpha\ln(T)$ w
Externí odkaz:
http://arxiv.org/abs/2212.05605
Autor:
Murorunkwere, Beatrice, Twagirayezu, Fidele, Munyeshyaka, Albert, Ntahompagaze, Joseph, Ayirwanda, Abraham
The equivalence between $f(R)$ and scalar-tensor theories is revisited, we consequently explored different $f(R)$ models. After consideration of specific definition of the scalar field, we derived the potentials $V(\phi)$ for each $f(R)$ model focusi
Externí odkaz:
http://arxiv.org/abs/2205.12115
Autor:
Paliathanasis, Andronikos, Leon, Genly
Publikováno v:
Math Meth Appl Sci. 2022;1-18 (2022)
We investigate exact solutions and the asymptotic dynamics for the Friedmann-Lema\^{\i}tre-Robertson-Walker universe with nonzero spatial curvature in the fourth-order modified teleparallel gravitational theory known as $f\left( T, B\right) $ theory.
Externí odkaz:
http://arxiv.org/abs/2201.12189
Autor:
Scomparin, Mattia
We discuss a no-go theorem for the novel Ricci-inverse theory of gravity. Referring to a static spherically symmetric matter distribution embedded in a de Sitter cosmology, we prove that it is impossible to have a stable Sub-Horizon non-relativistic
Externí odkaz:
http://arxiv.org/abs/2102.04676
Autor:
Shenavar, Hossein, Javidan, Kurosh
Publikováno v:
Universe 2020, 6(1), 1
Wheeler (1964) had formulated Mach's principle as the boundary condition for general relativistic field equations. Here, we use this idea and develop a modified dynamical model of cosmology based on imposing Neumann boundary condition on cosmological
Externí odkaz:
http://arxiv.org/abs/1810.05001
Autor:
Ghosh, Kaushik
In this manuscript, we will discuss the construction of covariant derivative operator in quantum gravity. We will find it is more perceptive to use affine connections more general than metric compatible connections in quantum gravity. We will demonst
Externí odkaz:
http://arxiv.org/abs/1702.02384
Autor:
Schmidt, H. -J., Singleton, D.
Publikováno v:
J.Math.Phys. 54 (2013) 062502
We study a broad class of isotropic vacuum cosmologies in fourth-order gravity under the condition that the gravitational Lagrangian be scale-invariant or almost scale-invariant. The gravitational Lagrangians considered will be of the form L = f(R) +
Externí odkaz:
http://arxiv.org/abs/1212.1769
f ( T , B ) gravity in a Friedmann–Lemaître–Robertson–Walker universe with nonzero spatial curvature
Autor:
Andronikos Paliathanasis, Genly Leon
Publikováno v:
Mathematical Methods in the Applied Sciences. 46:3905-3922
We investigate exact solutions and the asymptotic dynamics for the Friedmann-Lema\^{\i}tre-Robertson-Walker universe with nonzero spatial curvature in the fourth-order modified teleparallel gravitational theory known as $f\left( T, B\right) $ theory.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::c00d2d5400d90e3b8a213de85caebf0d
https://doi.org/10.1002/mma.8728
https://doi.org/10.1002/mma.8728
