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Related papers: Anisotropic constant-roll inflation for the Dirac-…

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Braneworld cosmology supported by a bulk scalar field with an exponential potential is developed. A general class of separable backgrounds for both single and two-brane systems is derived, where the bulk metric components are given by…

High Energy Physics - Theory · Physics 2008-04-22 James E. Lidsey , David Seery

We investigate the inflationary universe in a theory where two scalar fields non-minimally coupling to the scalar curvature and an extra $R^2$ term exist and the conformal invariance is broken. In particular, the slow-roll inflation is…

High Energy Physics - Theory · Physics 2016-03-01 Kazuharu Bamba

Non-abelian gauge field inflation is studied in the context of warm inflation scenario. We introduce this scenario as a mechanism that gives an end for gauge-flation model. Slow-roll parameters and perturbation parameters are presented for…

General Relativity and Quantum Cosmology · Physics 2015-06-17 M. R. Setare , V. Kamali

In the framework of Born-Infeld inspired gravity theories, which deviates from General Relativity (GR) in the high curvature regime, we discuss the viability of Cosmic Inflation without scalar fields. For energy densities higher than the…

General Relativity and Quantum Cosmology · Physics 2016-03-10 Jose Beltran Jimenez , Lavinia Heisenberg , Gonzalo J. Olmo , Christophe Ringeval

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

We extend the Randall-Sundrum(RS) model by adding a fundamental scalar field in the bulk, then study the multi-field assisted inflationary solution on brane. We will show that this model satisfies not only the observation, but also provides…

High Energy Physics - Phenomenology · Physics 2019-08-17 Yun_Song Piao , Wenbin Lin , Xinmin Zhang , Yuan-Zhong Zhang

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…

General Relativity and Quantum Cosmology · Physics 2017-12-06 S. Nojiri , S. D. Odintsov , V. K. Oikonomou

In this work we study slow-roll inflation for a vector-tensor model with massive vector fields non-minimally coupled to gravity. The model under consideration has arbitrary parameters for each geometrical coupling. Taking into account a…

General Relativity and Quantum Cosmology · Physics 2016-12-21 A. Oliveros

We initiate a non-perturbative study of anisotropic, non-conformal and confining gauge theories that are holographically realized in gravity by generic Einstein-Axion-Dilaton systems. In the vacuum our solutions describe RG flows from a…

High Energy Physics - Theory · Physics 2018-09-25 Dimitrios Giataganas , Umut Gürsoy , Juan F. Pedraza

We consider the Einstein equations within the DBI scenario for a spatially flat Friedmann-Robertson-Walker (FRW) spacetime without a cosmological constant. We derive the inflationary scenario by applying the symmetry transformations which…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-22 L. P. Chimento , R. Lazkoz , M. G. Richarte

Recently it was found that a broad class of existing inflationary models based on supergravity can be significantly simplified if some of the standard, unconstrained chiral superfields are replaced by nilpotent superfields, associated with…

High Energy Physics - Theory · Physics 2015-06-22 Renata Kallosh , Andrei Linde

Anomalies in recent observational data indicate that there might be some "anisotropic hair" generated in an inflation period. To obtain general information about the effects of this anisotropic hair to inflation models, we studied…

High Energy Physics - Phenomenology · Physics 2015-12-09 Jiaming Shi , Xiaotian Huang , Taotao Qiu

In previous work, two of us have proposed a model of inflationary magnetogenesis based on a rolling auxiliary field able both to account for the magnetic fields inferred by the (non) observation of gamma-rays from blazars, and to start the…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-13 Chiara Caprini , Maria Chiara Guzzetti , Lorenzo Sorbo

A new cosmological solution of the gravitational field equations in the generalized Randall-Sundrum model for an anisotropic brane with Bianchi I geometry and with perfect fluid as matter sources is presented. The matter is described by a…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Bikash Chandra Paul

We investigate the dynamics of the recently proposed model of assisted inflation. In this model an arbitrary number of scalar fields with exponential potentials evolve towards an inflationary scaling solution, even if each of the individual…

Astrophysics · Physics 2016-08-25 Karim A. Malik , David Wands

Inflation due to a non-minimally coupled scalar field with a large non-minimal coupling, as first proposed by Salopek, Bardeen and Bond (SBB), is in good agreement with the observed value of the spectral index and constraints on the…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-17 John McDonald

We investigate a cosmological solution within the framework of a 5D standing wave braneworld model generated by gravity coupled to a massless scalar phantom-like field. By obtaining a full exact solution of the model we found a novel…

High Energy Physics - Theory · Physics 2015-06-04 Merab Gogberashvili , Alfredo Herrera-Aguilar , Dagoberto Malagon-Morejon , Refugio Rigel Mora-Luna

We study the linear perturbation of the recently proposed model of inflation where a uniform gauge-kinetic coupling of the inflaton to multiple vector fields breaks the cosmic no-hair conjecture while maintaining the isotropy. We derive the…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-09 Kei Yamamoto

We consider a noncommutative (NC) inflationary model with a homogeneous scalar field minimally coupled to gravity. The particular NC inflationary setting produces entirely new consequences. We first analyze the free field case and…

General Relativity and Quantum Cosmology · Physics 2018-05-01 S. M. M. Rasouli , N. Saba , M. Farhoudi , J. Marto , P. Moniz

We investigate the cosmological evolution of the system of a Dirac-Born-Infeld field plus a perfect fluid. We analyze the existence and stability of scaling solutions for the AdS throat and the quadratic potential. We find that the scaling…

High Energy Physics - Theory · Physics 2014-11-18 Zong-Kuan Guo , Nobuyoshi Ohta