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Related papers: Flow equations in generalized braneworld scenarios

200 papers

I generalize the inflationary flow equations of Hoffman and Turner to arbitrary order in slow roll. This makes it possible to study the predictions of slow roll inflation in the full observable parameter space of tensor/scalar ratio $r$,…

Astrophysics · Physics 2009-11-07 William H. Kinney

We analyze solutions to Friedmann-Robertson-Walker cosmologies in Brans-Dicke theory, where a scalar field is coupled to gravity. Matter is modelled by a $\gamma$-law perfect fluid, including false-vacuum energy as a special case. Through a…

General Relativity and Quantum Cosmology · Physics 2011-07-19 Shawn J. Kolitch , Douglas M. Eardley

We apply a very simple procedure to construct non-singular cosmological models for flat Friedmann universes filled with minimally coupled scalar fields or by tachyon Born-Infeld-type fields. Remarkably, for the minimally coupled scalar…

General Relativity and Quantum Cosmology · Physics 2024-03-14 Alexander Kamenshchik , Polina Petriakova

The braneworld cosmology, in which our universe is imbedded as a hypersurface in a higher dimensional bulk, has the peculiar property that the inflationary consistency relation derived in a four-dimensional cosmology persists. This…

Astrophysics · Physics 2008-04-22 David Seery , Andy Taylor

We examine the full nonlinear dynamics of closed FRW universes in the framework of D-branes formalism. Friedmann equations contain additional terms arising from the bulk-brane interaction that provide a concrete model for nonsingular…

General Relativity and Quantum Cosmology · Physics 2013-01-23 Rodrigo Maier , Ivano Damião Soares , Eduardo Valentino Tonini

We study the Friedmann equation for the warped codimension-two braneworld background which most closely resembles the Randall-Sundrum model. Extra matter on the (Planck) 4-brane, with equation of state p_\theta=(\alpha-1)\rho for the…

High Energy Physics - Theory · Physics 2008-11-26 Fang Chen , James M. Cline , Sugumi Kanno

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

The brane-world scenario provides an intriguing possibility to explore the phenomenological cosmology implied by string/M theory. In this paper, we consider a modified Randall-Sundrum single brane model with two natural generalizations: a…

High Energy Physics - Theory · Physics 2014-05-06 Mariam Bouhmadi-Lopez , Yen-Wei Liu , Keisuke Izumi , Pisin Chen

We calculate the spectral index and tensor-to-scalar ratio for patch inflation arisen from the Gauss-Bonnet braneworld scenario. The patch cosmological models consist of Gauss-Bonnet (GB), Randall-Sundrum (RS), and 4D general relativistic…

Astrophysics · Physics 2010-04-05 Hungsoo Kim , Kyong Hee Kim , Hyung Won Lee , Yun Soo Myung

We review some general aspects of braneworld cosmologies in which an inflationary period driven by a scalar field confined on the brane is described by a nonstandard effective Friedmann equation. The perturbation spectra, consistency…

High Energy Physics - Theory · Physics 2007-05-23 Gianluca Calcagni

We study inflationary universe models that are characterized by a single scalar inflaton field. The study of these models are based on two dynamical equations; one corresponding to the Klein-Gordon equation for the inflaton field, and the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Sergio del Campo

We compare the simplest realistic brane inflationary model to recent cosmological data, including WMAP 3-year cosmic microwave background (CMB) results, Sloan Digital Sky Survey luminous red galaxies (SDSS LRG) power spectrum data and…

High Energy Physics - Theory · Physics 2010-10-27 Rachel Bean , Sarah E. Shandera , S. H. Henry Tye , Jiajun Xu

We present here the general transformation that leaves unchanged the form of the field equations for perfect fluid cosmologies in the DGP braneworld model. Specifically, a prescription for relating exact solutions with different equations…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Ruth Lazkoz

We demonstrate the attractor behavior of inflation driven by a scalar field or a tachyon field in the context of recently proposed four-dimensional effective gravity induced on the world-volume of a three-brane in five-dimensional Einstein…

High Energy Physics - Phenomenology · Physics 2009-11-10 Zong-Kuan Guo , Hong-Sheng Zhang , Yuan-Zhong Zhang

In this lecture I will review the present status of inflation within string-based brane-world scenarios. The idea is to start from a supersymmetric configuration with two parallel static Dp-branes, and slightly break the supersymmetry…

Astrophysics · Physics 2007-05-23 Juan Garcia-Bellido

In the context of an inflationary Randall-Sundrum Type II braneworld (RS2) we calculate spectral indices and amplitudes of cosmological scalar and tensor perturbations, up to second order in slow-roll parameters. Under very simple…

High Energy Physics - Phenomenology · Physics 2009-11-10 Gianluca Calcagni

In this manuscript we use the dynamical system approach to study the linear dynamics of a Randall-Sundrum braneworld model with a tachyon scalar field confined to the brane. We recognize that the form of the tachyon potential plays a…

General Relativity and Quantum Cosmology · Physics 2020-05-27 Arvin Ravanpak , Golnaz Farpour Fadakar

The inflationary scenario for the brane world driven by the bulk inflaton is proposed. The quantum fluctuations of the inflaton is calculated and compared to those of the conventional 4-dimensional inflationary scenario. It is shown that…

High Energy Physics - Theory · Physics 2009-10-31 Shinpei Kobayashi , Kazuya Koyama , Jiro Soda

An introductory review of the Randall-Sundrum type II braneworld scenario is presented, with emphasis on the relationship between the density and gravitational wave perturbations that are generated during inflation. The implications of…

Astrophysics · Physics 2017-08-23 James E. Lidsey

We describe a simple mechanism that can lead to inflation within string-based brane-world scenarios. The idea is to start from a supersymmetric configuration with two parallel static Dp-branes, and slightly break the supersymmetry…

High Energy Physics - Theory · Physics 2014-11-18 J. Garcia-Bellido , R. Rabadan , F. Zamora