English
Related papers

Related papers: $\alpha$-attractor from superconformal E-models in…

200 papers

Some observational constraints on the brane-world based on predictions from specific models in five dimensions, have been recently reported, both on local and cosmological scales. In order to identify the origins of these constraints, the…

Astrophysics · Physics 2007-05-23 M. D. Maia , E. M. Monte

High-energy modifications to general relativity introduce changes to the perturbations generated during inflation, and the latest high-precision cosmological data can be used to place constraints on such modified inflation models. Recently…

Astrophysics · Physics 2009-11-10 Shinji Tsujikawa , M. Sami , Roy Maartens

Cosmological $\alpha$-attractors are a compelling class of inflationary models. They lead to universal predictions for large-scale observables, broadly independent from the functional form of the inflaton potential. In this work we derive…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-21 Laura Iacconi , Matteo Fasiello , Jussi Väliviita , David Wands

The possibility of linking inflation and late cosmic accelerated expansion using the $\alpha$-attractor models has received increasing attention due to their physical motivation. In the early universe, $\alpha$-attractors provide an…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-21 Carlos García-García , Eric V. Linder , Pilar Ruíz-Lapuente , Miguel Zumalacárregui

In this article we study a constant-roll inflationary model in the context of brane-world cosmology caused by a quintessence scalar field for warm inflation with a constant dissipative parameter Q =$\Gamma$/3H. We determine the analytical…

General Relativity and Quantum Cosmology · Physics 2022-01-11 Mohammad Reza Setare , Arvin Ravanpak , Karam Bahari , Golnaz Farpour Fadakar

Upper bounds on the energy scale at the end of inflation in the Randall-Sundrum type II braneworld scenario are derived. The analysis is made exact by introducing new parameters that represent extensions of the Hubble flow parameters. Only…

Astrophysics · Physics 2009-11-07 Rachael M. Hawkins , James E. Lidsey

We show that the universal $\alpha$-attractor models of inflation can be realized by including an auxiliary vector field $A_{\mu}$ for the Starobinsky model with the Lagrangian $f(R)=R+R^2/(6M^2)$. If the same procedure is applied to…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-24 Mehmet Ozkan , Yi Pang , Shinji Tsujikawa

We consider a braneworld inflation model driven by the dynamics of a scalar field living in the 5-dimensional bulk, the so-called ``bulk inflaton model'', and investigate the geometry in the bulk and large scale cosmological perturbations…

General Relativity and Quantum Cosmology · Physics 2009-10-09 Masato Minamitsuji , Yoshiaki Himemoto , Misao Sasaki

We obtain cosmological constraints on models of inflation which exhibit rapid roll solutions. Rapid roll attractors exist for potentials with large mass terms and are thus of interest for inflationary model building within string theory. We…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-15 Takeshi Kobayashi , Shinji Mukohyama , Brian A. Powell

We investigate recent claims that brane inflation solves the overshoot problem through a combination of microphysical restrictions on the phase space of initial conditions and the existence of the Dirac-Born-Infeld (DBI) attractor in…

High Energy Physics - Theory · Physics 2009-09-02 Simeon Bird , Hiranya V. Peiris , Daniel Baumann

Fibre inflation is a specific string theory construction based on the Large Volume Scenario that produces an inflationary plateau. We outline its relation to $\alpha$-attractor models for inflation, with the cosmological sector originating…

High Energy Physics - Theory · Physics 2018-04-04 Renata Kallosh , Andrei Linde , Diederik Roest , Alexander Westphal , Yusuke Yamada

We investigate the observational viability of a class of $\alpha$-attractors inflationary models in light of the most recent Cosmic Microwave Background (CMB) and Large-Scale Structure (LSS) data. By considering a double-well potential we…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-04 J. G. Rodrigues , S. Santos da Costa , J. S. Alcaniz

We consider a generalization of the Randall-Sundrum single brane-world scenario (RS2). More precisely, the generalization is described through curvature corrections, corresponding to a Gauss-Bonnet term in the bulk and a Hilbert-Einstein…

General Relativity and Quantum Cosmology · Physics 2013-05-30 Mariam Bouhmadi-Lopez , Pisin Chen , Yen-Wei Liu

Inflationary cosmology is developed in the second Randall-Sundrum braneworld scenario, where the accelerated expansion arises through potentials that are too steep to drive inflation in conventional cosmology. A relationship between the…

Astrophysics · Physics 2009-11-06 Greg Huey , James E. Lidsey

We compute the cosmological perturbations generated in the brane world inflation driven by the bulk inflaton. Different from the model that the inflation is a brane effect, we exhibit the modification of the power spectrum of scalar…

High Energy Physics - Theory · Physics 2009-11-10 Bin Wang , Li-Hui Xue , Xinmin Zhang , W-Y. P. Hwang

In the present work warm inflationary universe model with viscous pressure on the brane in high-dissipation regime is studied. We derive a condition which is required for this model to be realizable in slow-roll approximation. We also…

General Physics · Physics 2014-10-07 M. R. Setare , V. Kamali

We investigate in detail the attractor behavior of some inflationary models based on braneworld dynamics under the constant-roll condition. We describe the dynamics of the models, assuming that the second slow-roll parameter remains…

General Relativity and Quantum Cosmology · Physics 2025-04-29 Goran S. Djordjevic , Neven Bilić , Dragoljub D. Dimitrijevic , Milan Milosevic , Marko Stojanovic

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

We consider a Chaplygin gas model with an exponential potential in framework of braneworld inflation. We apply the slow-roll approximation in the high-energy limit to derive various inflationary spectrum perturbation parameters. We show…

High Energy Physics - Theory · Physics 2014-08-12 R. Zarrouki , M. Bennai

We investigate the early universe evolution in the context of brane inflation driven by a supergravity-inspired $\arctan$ potential. We performed a slow-roll and a semi-analytical reheating analyses and obtained constraints on the…

High Energy Physics - Theory · Physics 2022-07-18 R. M. P. Neves , S. Santos da Costa , F. A. Brito , J. S. Alcaniz