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Unifying an asymmetric bounce to the dark energy in Chern–Simons F(R) gravity
(Physics of the Dark Universe, 2021)
We propose a cosmological scenario in which the universe undergoes through a non-singular bounce,
and after the bounce, it decelerates having a matter-like dominated evolution during some regime
of the deceleration era, and finally at the present epoch it evolves through an accelerating stage.
Our aim is to study such evolution in the context of Chern–Simons corrected F(R) ...
Inflation from the Symmetry of the Generalized Cosmological Model
(Symmetry, 2021)
It is shown that the inflationary model is the result of the symmetry of the generalized
F(R, T, X, ϕ)-cosmological model using the Noether symmetry. It leads to a solution, a particular
case of which is Starobinsky’s cosmological model. It is shown that even in the more particular case
of cosmological models F(R, X, ϕ) and F(T, X, ϕ) the Monge–Ampère equation is still obtained, ...
Spectrum of Primordial Gravitational Waves in Modified Gravities: A Short Overview
(Symmetry, 2022)
In this work, we shall exhaustively study the effects of modified gravity on the energy
spectrum of the primordial gravitational waves background. S. Weinberg has also produced significant works related to the primordial gravitational waves, with the most important one being
the effects of neutrinos on primordial gravitational waves. With this short review, our main aim is
to ...
Metric-Affine Myrzakulov Gravity Theories
(Symmetry, 2021)
In this paper, we review the so-called Myrzakulov Gravity models (MG-N, with N = I, II, . . . ,
VIII) and derive their respective metric-affine generalizations (MAMG-N), discussing also their
particular sub-cases. The field equations of the theories are obtained by regarding the metric tensor
and the general affine connection as independent variables. We then focus on the case ...
General Slow-Roll Inflation in f (R) Gravity under the Palatini Approach
(Symmetry, 2020)
Slow-roll inflation is analyzed in the context of modified gravity within the Palatini
formalism. As shown in the literature, inflation in this framework requires the presence of non-traceless
matter; otherwise, it does not occur just as a consequence of the nonlinear gravitational terms of the
action. Nevertheless, by including a single scalar field that plays the role of the ...
Metric-Affine Myrzakulov Gravity Theories
(Symmetry, 2021)
In this paper, we review the so-called Myrzakulov Gravity models (MG-N, with N = I, II, . . . ,
VIII) and derive their respective metric-affine generalizations (MAMG-N), discussing also their
particular sub-cases. The field equations of the theories are obtained by regarding the metric tensor
and the general affine connection as independent variables. We then focus on the case ...
Soliton surfaces induced by the Fokas-Lenells equation
(Journal of Physics: Conference Series, 2019)
Late Time Attractors of Some Varying Chaplygin Gas Cosmological Models
(Symmetry, 2021)
The goal of this paper is to study new cosmological models where the dark energy is
a varying Chaplygin gas. This specific dark energy model with non-linear EoS had been often
discussed in modern cosmology. Contrary to previous studies, we consider new forms of nonlinear non-gravitational interaction between dark matter and assumed dark energy models. We
applied the phase space ...
Mimetic Attractors
(International Journal of Theoretical Physics, 2016)
In this paper,we investigate the mathematical modeling for the cosmological
attractors propagated in mimetic gravity upon which an interacting dark energy-dark matter
is supposed to be existed. The average value of the interaction of these percentages, namely
i say, may be used to investigate generally the modeling of an attractor; the actual value
could only be determined ...










