中文
相关论文

相关论文: Cosmic evolution of the logarithmic f(R) model and…

200 篇论文

In this paper, we consider an inflationary model of $f(R)$ gravity with polynomial form plus logarithmic term. We calculate some cosmological parameters and compare our results with the Plank 2015 data. We find that presence of both…

广义相对论与量子宇宙学 · 物理学 2016-06-14 J. Sadeghi , B. Pourhassan , A. S. Kubeka , M. Rostami

In this paper, we use corrected $f(R)$ gravitational model which is polynomial function with a logarithmic term. In that case, we employ the slow-roll condition and obtain the number of cosmological parameter. This help us to verify the…

高能物理 - 理论 · 物理学 2019-11-12 J. Sadeghi , E. Naghd Mezerji , S. Noori Gashti

We propose the study of constant-roll inflation in $F(R)$ gravity. We use two different approaches, one that relates an $F(R)$ gravity to well known scalar models of constant-roll and a second that examines directly the constant-roll…

广义相对论与量子宇宙学 · 物理学 2017-12-06 S. Nojiri , S. D. Odintsov , V. K. Oikonomou

In this paper we investigate the inflationary dynamics of an $f(R)$ gravity in the presence of a canonical scalar field. We specifically choose the cosmological evolution to be a quasi-de Sitter evolution and also the $f(R)$ gravity is…

广义相对论与量子宇宙学 · 物理学 2018-08-01 K. Kleidis , V. K. Oikonomou

We investigate in detail the implications of the constant-roll condition on the inflationary era of a scalar field coupled to a teleparallel $f(T)$ gravity. The resulting cosmological equations constitute a reconstruction technique which…

广义相对论与量子宇宙学 · 物理学 2018-07-17 A. Awad , W. El Hanafy , G. G. L. Nashed , S. D. Odintsov , V. K. Oikonomou

Inflationary models derived from $f(R)$ gravity, where the scalaron rolls down with a constant rate from the top to the minimum of the effective potential, are considered. Specifically, we take into account three $f(R)$ models…

广义相对论与量子宇宙学 · 物理学 2021-08-16 Mehdi Shokri , Mohammad Reza Setare , Salvatore Capozziello , Jafar Sadeghi

In this work we shall investigate the phenomenological implications of the constant-roll condition on a $k$-Inflation theory of gravity. The latter theories are particularly promising, since these remained robust to the results of GW170817,…

广义相对论与量子宇宙学 · 物理学 2020-01-29 S. D. Odintsov , V. K. Oikonomou

In this paper, we study a theory of gravity called mimetic $f(R, T)$ in the presence of swampland dS conjecture. For this purpose, we introduce several inflation solutions of the Hubble parameter H(N) from $f(R, T)= R+\delta T$ gravity…

广义相对论与量子宇宙学 · 物理学 2022-08-26 S. Noori Gashti , J. Sadeghi , S. Upadhyay , M. R. Alipour

Over the past few decades, inflation models have been studied by researchers from different perspectives and conditions in order to introduce a model for the expanding universe. In this paper, we introduce a modified $f(R)$ gravitational…

广义相对论与量子宇宙学 · 物理学 2021-12-01 J. Sadeghi , B. Pourhassan , S. Noori Gashti , S. Upadhyay

In this paper we investigate the inflationary phenomenology of an Einstein-Gauss-Bonnet theory with the extension of a logarithmic modified $f(R)$ gravity, compatible with the GW170817 event. The main idea of our work is to study different…

广义相对论与量子宇宙学 · 物理学 2021-03-03 S. A. Venikoudis , F. P. Fronimos

In this paper we investigate the asymptotic dynamics of inflationary cosmological models that are based in scalar-tensor theories of gravity. Our main aim is to explore the global structure of the phase space in the framework of…

广义相对论与量子宇宙学 · 物理学 2020-05-20 Israel Quiros , Tame Gonzalez , Roberto De Arcia , Ricardo García-Salcedo , Ulises Nucamendi , Joel F. Saavedra

Inflation in the framework of $f(R)$ modified gravity is revisited. We study the conditions that $f(R)$ should satisfy in order to lead to a viable inflationary model in the original form and in the Einstein frame. Based on these criteria…

高能物理 - 理论 · 物理学 2018-10-17 M. Amin , S. Khalil , M. Salah

We generalize the notion of constant-roll inflation earlier introduced in General Relativity (GR) and $f(R)$ gravity to inflationary models in more general scalar-tensor gravity. A number of novel exact analytic solutions for a FLRW…

广义相对论与量子宇宙学 · 物理学 2020-02-25 Hayato Motohashi , Alexei A. Starobinsky

We investigate the cosmic inflation scenario of a specific $f(R)$ model that contains more than one higher-order term in $R$. The $f(R)$ considered here has the terms $R^2$, $R^3$, and $R^4$ along with the linear term. A rigorous…

广义相对论与量子宇宙学 · 物理学 2022-11-16 Sahazada Aziz , Sohan Kumar Jha , Anisur Rahaman

The previously introduced class of two-parametric phenomenological inflationary models in General Relativity in which the slow-roll assumption is replaced by the more general, constant-roll condition is generalized to the case of $f(R)$…

宇宙学与河外天体物理 · 物理学 2017-08-15 Hayato Motohashi , Alexei A. Starobinsky

In this paper, we study a constant-roll inflationary model in the presence of a noncommutative parameter with a homogeneous scalar field minimally coupled to gravity. The specific noncommutative inflation conditions proposed new…

高能物理 - 理论 · 物理学 2023-02-14 J. Sadeghi , S. Noori Gashti

In this paper we shall consider an exponential inflationary model in the context of vacuum $F(R)$ gravity. By using well-known reconstruction techniques, we shall investigate which $F(R)$ gravity can realize the exponential inflation…

广义相对论与量子宇宙学 · 物理学 2018-03-14 V. K. Oikonomou

This paper discusses a simple procedure to reconstruct f (R)-gravity models from exact cosmological solutions of the Einstein field equations with a noninteracting classical scalar field-and-radiation background. From the kind of…

广义相对论与量子宇宙学 · 物理学 2017-09-15 Heba Sami , Joseph Ntahompagaze , Amare Abebe

In this article we study a constant-roll inflationary model in the context of the DGP brane-world cosmology caused by a quintessence scalar field. We determine an analytical solution for the Friedman equation coupled to the equation of…

广义相对论与量子宇宙学 · 物理学 2022-10-20 Arvin Ravanpak , Golnaz Farpour Fadakar

We present uniform rate inflation in a modified $f(T, \mathcal{T}) $ gravity. It is found that early inflation can be realized even with a scalar field field with a quadratic potential and a negative cosmological constant. We construct…

广义相对论与量子宇宙学 · 物理学 2025-07-02 Priyanka Mandal , B. C. Paul
‹ 上一页 1 2 3 10 下一页 ›