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Related papers: G-constant-roll inflation

200 papers

Slow-roll inflation is studied in theories where the inflaton field is conformally coupled to the Ricci scalar. In particular, the case of Higgs field inflation in the context of the noncommutative spectral action is analyzed. It is shown…

High Energy Physics - Theory · Physics 2010-08-31 Michel Buck , Malcolm Fairbairn , Mairi Sakellariadou

Recently a class of inflationary models satisfying the constant rate of roll constraint, $\ddot{\phi}+(3+\alpha)H\dot{\phi}=0$, has been studied and compared with the latest cosmological observational data. We consider the broader class of…

General Relativity and Quantum Cosmology · Physics 2019-11-11 B. Boisseau , H. Giacomini

Nonminimal coupling of the inflaton field to the Ricci curvature of spacetime is generally unavoidable, and the paradigm of inflation should be generalized by including the corresponding term in the Lagrangian of the inflationary theory.…

High Energy Physics - Theory · Physics 2014-11-18 Valerio Faraoni

Constant roll inflation is analyzed in the presence of multi scalar fields which are assumed to be described by a constant roll rate each. The different cases are studied and the corresponding potentials are reconstructed. The exact…

General Relativity and Quantum Cosmology · Physics 2021-01-04 Merce Guerrero , Diego Rubiera-Garcia , Diego Saez-Chillon Gomez

For the constant-roll tachyon inflation, we derive the analytical expressions for the scalar and tensor power spectra, the scalar and tensor spectral tilts and the tensor to scalar ratio up to the first order by using the method of Bessel…

General Relativity and Quantum Cosmology · Physics 2018-05-03 Qing Gao , Yungui Gong , Qin Fei

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,…

General Relativity and Quantum Cosmology · Physics 2020-01-29 S. D. Odintsov , V. K. Oikonomou

The reconstruction of an inflationary universe in the context of the Galileon model or G-model, considering as attractors the scalar spectral index $n_S(N)$ and the tensor to scalar ratio $r(N)$ as a function of the number of e-folding $N$…

General Relativity and Quantum Cosmology · Physics 2018-08-08 Ramon Herrera

We consider the constant-roll condition in the model of the inflaton nonminimal coupling to the Gauss-Bonnet term. By assuming the first Gauss-Bonnet flow parameter $\delta_1$ is a constant, we discuss the constant-roll inflation with…

General Relativity and Quantum Cosmology · Physics 2020-12-02 Tie-Jun Gao

Generalized slow roll conditions and parameters are obtained for a general form of scalar-tensor theory (with no external sources), having arbitrary functions describing a nonminimal gravitational coupling F(\phi), a Kahler-like kinetic…

General Relativity and Quantum Cosmology · Physics 2009-11-07 J. R. Morris

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…

General Relativity and Quantum Cosmology · Physics 2020-02-25 Hayato Motohashi , Alexei A. Starobinsky

We propose a new class of inflation model, G-inflation, which has a Galileon-like nonlinear derivative interaction of the form $G(\phi, (\nabla\phi)^2)\Box\phi$ in the Lagrangian with the resultant equations of motion being of second order.…

High Energy Physics - Theory · Physics 2010-12-28 Tsutomu Kobayashi , Masahide Yamaguchi , Jun'ichi Yokoyama

Departing from standard slow-roll conditions is one way of putting the inflationary paradigm to test, and constraining the dynamics of the inflaton field with a constant-rate of roll of the inflaton field, a.k.a. the constant-roll scenario,…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-19 Sandip Biswas , Kaushik Bhattacharya , Suratna Das

We study constant-roll inflation using the $\beta$-function formalism. We show that the constant rate of the inflaton roll is translated into a first order differential equation for the $\beta$-function which can be solved easily. The…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-09 F. Cicciarella , J. Mabillard , M. Pieroni

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 $f(R)$…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-15 Hayato Motohashi , Alexei A. Starobinsky

The Generalized Chaplygin Gas (GCG) model is characterized by the equation of state $P = -A \rho^{-\alpha}$, where $A>0$ and $\alpha < 1$. The model has been extensively studied due to its interesting properties and applicability in several…

General Relativity and Quantum Cosmology · Physics 2021-01-01 Alexander Gallego Cadavid , J. R. Villanueva

The scenario of constant-roll inflation is studied where the inflaton is a scalar field with modified kinetic term, known as non-canonical scalar field. This modification leads to some changes in the slow-roll parameters, and also by taking…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-23 Abolhassan Mohammadi , Khaled Saaidi , Haidar Sheikhahmadi

Recently, it has been realized that the so-called G-inflation model inspired by supplementing a generalized covariant Galileon-like non-linear derivative self-interacting term to the standard kinetic term should be ruled out from…

General Relativity and Quantum Cosmology · Physics 2017-12-06 Maysam Motaharfar , Erfan Massaeli , Hamid Reza Sepangi

In this paper we investigate the inflationary phenomenology of an Einstein-Gauss-Bonnet theory compatible with the GW170817 event, by imposing the constant-roll evolution on the scalar field. We develop the constant-roll GW170817-compatible…

General Relativity and Quantum Cosmology · Physics 2020-09-15 S. D. Odintsov , V. K. Oikonomou , F. P. Fronimos , S. A. Venikoudis

In our paper we consider the validity of slow-roll approximations for Gauss-Bonnet inflation introduced in [1]. In contrast to the cited paper where the coupling function before the Gauss-Bonnet term have been chosen as a decaying function…

General Relativity and Quantum Cosmology · Physics 2026-02-02 Bogdan A. Rudenko , Maria A. Skugoreva , Alexey V. Toporensky

In this paper we wish to point out the possibility of using a complex scalar field in a constant roll inflationary model, as needed for observational viability. We extend the idea of real field inflaton with constant rate of roll to a…

General Relativity and Quantum Cosmology · Physics 2023-07-04 Ali Mohammadi , Nahid Ahmadi , Mehdi Shokri