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Related papers: Starobinsky-like two-field inflation

200 papers

Models of cosmological inflation resembling the Starobinsky R + R^2 model emerge naturally among the effective potentials derived from no-scale SU(N,1)/SU(N) x U(1) supergravity when N > 1. We display several examples in the SU(2,1)/SU(2) x…

High Energy Physics - Theory · Physics 2015-06-16 John Ellis , Dimitri V. Nanopoulos , Keith A. Olive

We present a novel realization of Starobinsky-type inflation within Supergravity using two chiral superfields. The proposed superpotential is inspired by induced-gravity models. The Kaehler potential contains two logarithmic terms, one for…

High Energy Physics - Phenomenology · Physics 2016-07-08 C. Pallis , N. Toumbas

The magnitude of B-mode polarization in the cosmic microwave background as measured by BICEP2 favours models of chaotic inflation with a quadratic $m^2 \phi^2/2$ potential, whereas data from the Planck satellite favour a small value of the…

High Energy Physics - Phenomenology · Physics 2014-08-25 John Ellis , Marcos A. G. Garcia , Dimitri V. Nanopoulos , Keith A. Olive

We consider a non-canonic field in the context of Starobinsky inflation. We work in Einstein-frame. In this frame, the gravitational part of the action is equivalent to the Hilbert-Einstein action, plus a scalar field called scalaron. We…

General Relativity and Quantum Cosmology · Physics 2021-04-28 Salomeh Khoeini-Moghaddam

In this work we revisit $\alpha$-Starobinsky inflation, also know as $E$-model, in the light of current CMB and LSS observations. The inflaton potential in the Einstein frame for this model contains a parameter $\alpha$ in the exponential,…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-11 Saisandri Saini , Akhilesh Nautiyal

Motivated by the recent observation of the B-mode signal in the cosmic microwave background by BICEP2, we stuty the Starobinsky-type inflation model in the framework of old-minimal supergravity, where the inflaton field in the original…

High Energy Physics - Phenomenology · Physics 2014-05-15 Koichi Hamaguchi , Takeo Moroi , Takahiro Terada

We single out the Starobinsky model and its extensions among generic $f(R)$ gravity as attractors at large field values for chaotic inflation. Treating a $R^3$ curvature term as a perturbation of the Starobinsky model, we impose the…

High Energy Physics - Phenomenology · Physics 2020-05-05 Dhong Yeon Cheong , Hyun Min Lee , Seong Chan Park

We discuss how the higher-derivative Starobinsky model of inflation originates from N=1 supergravity. It is known that, in the old-minimal supergravity description written by employing a chiral compensator in the superconformal framework,…

High Energy Physics - Theory · Physics 2015-06-16 F. Farakos , A. Kehagias , A. Riotto

We analyze BI model in a complete form and compare the predictions with that of Starobinsky model. Under the parameter constraints in Planck 2018, we find that the dynamics of the whole inflation process described by BI and Starobinsky…

General Relativity and Quantum Cosmology · Physics 2019-12-05 Ping Kwan Man Ellgan

The $R+R^2$ model of gravity with the corresponding shallow potential in the Einstein frame is consistent with the observations. Recently, many efforts have been made to generalize the $R+R^2$ (Starobinsky) model of inflation or use other…

General Relativity and Quantum Cosmology · Physics 2023-02-08 Masud Chaichian , Amir Ghal'e , Markku Oksanen

We revisit the small field double-well inflationary model and investigate its observational viability in light of the current Cosmic Microwave Background data. In particular, considering scenarios with minimal and nonminimal coupling…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-27 G. Rodrigues , J. G. Rodrigues , F. B. M. dos Santos , J. S. Alcaniz

We introduce a modification of the Starobinsky model in the form of an additional cubic Ricci scalar curvature term $\sim \alpha R^3$, scaled by a dimensionless parameter $\alpha$, with the resulting inflaton potential being the standard…

General Relativity and Quantum Cosmology · Physics 2025-09-23 Ioannis D. Gialamas , Theodoros Katsoulas , Kyriakos Tamvakis

Starobinsky inflation is an attractive, fundamental model to explain the Planck measurements, and its higher-order extension may allow us to probe quantum gravity effects. We show that future CMB data combined with the 21cm intensity map…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-30 Tanmoy Modak , Lennart Röver , Björn Malte Schäfer , Benedikt Schosser , Tilman Plehn

This paper focuses on the Starobinsky model of inflation. We derive solutions for various cosmological observables, such as the scalar spectral index $n_s$, the tensor-to-scalar ratio $r$ and their runnings, as well as the number of…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-22 Gabriel German , Juan Carlos Hidalgo , Luis E. Padilla

The recent detection by the BICEP2 collaboration of a high level of tensor modes seems to exclude the Starobinsky model of inflation. In this paper we show that this conclusion can be avoided: one can embed the Starobinsky model in…

High Energy Physics - Theory · Physics 2015-06-19 Sergio Ferrara , Alex Kehagias , Antonio Riotto

Inflation in cosmology is a specific stage preceding the Big Bang, aimed at solving both old background problems and new perturbation issues. Single-field inflation is a candidate to illustrate the picture of the initial universe, and…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-21 Guanqiao Liu

Using a no-scale supergravity framework, we construct an SO(10) model that makes predictions for cosmic microwave background observables similar to those of the Starobinsky model of inflation, and incorporates a double-seesaw model for…

High Energy Physics - Phenomenology · Physics 2016-11-15 John Ellis , Marcos A. G. Garcia , Natsumi Nagata , Dimitri V. Nanopoulos , Keith A. Olive

We analyze the Starobinsky inflation model and the impact of curvature corrections, particularly a cubic $R^3$ term, to assess their behavior in light of the latest observational results from the Atacama Cosmology Telescope (ACT). With the…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-30 J. Bezerra-Sobrinho , L. G. Medeiros

Starobinsky inflation is currently one of the best models concerning agreement with cosmological data. Despite this observational success, it is still lacking a robust embedding into a UV complete theory. Previous efforts to derive…

High Energy Physics - Theory · Physics 2024-01-18 Max Brinkmann , Michele Cicoli , Pietro Zito

We calculate the scalar spectral index $n_s$ and the tensor-to-scalar ratio $r$ in a class of recently proposed two-field no-scale inflationary models in supergravity. We show that, in order to obtain correct predictions, it is crucial to…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Sébastien Renaux-Petel , Krzysztof Turzynski