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Related papers: Brane inflation without slow-roll

200 papers

The curvaton and the inhomogeneous reheating scenarios for the generation of the cosmological curvature perturbation on large scales represent an alternative to the standard slow-roll scenario where the observed density perturbations are…

Astrophysics · Physics 2009-11-10 L. Pilo , A. Riotto , A. Zaffaroni

We describe a model of D--brane inflation on fractional D3 branes transverse to a resolved and deformed conifold. The resolution and the deformation are both necessary for inflation. The fractional branes slowly approach each other along…

High Energy Physics - Theory · Physics 2007-05-23 Edi Halyo

We consider a model of inflation which has recently been proposed in the literature and where inflation is induced by corrections to the energy density coming from the non-commutativity of spacetime. We show that the very rapid inflationary…

General Relativity and Quantum Cosmology · Physics 2013-01-14 Hideki Perrier , Ruth Durrer , Massimiliano Rinaldi

It is shown that a large class of higher-order (i.e. non-quadratic) scalar kinetic terms can, without the help of potential terms, drive an inflationary evolution starting from rather generic initial conditions. In many models, this…

High Energy Physics - Theory · Physics 2008-11-26 C. Armendariz-Picon , T. Damour , V. Mukhanov

I discuss why quintessential inflation model-building is more natural in the context of brane cosmology and study the dynamics of a particular model as an example.

Astrophysics · Physics 2007-05-23 Konstantinos Dimopoulos

We address the issue of slow-roll in string theory models of inflation. Using a K\"{a}hler transformation and results from the D3-D7 model, we show why we expect flat directions to be present and slow-roll to be possible in general. We…

High Energy Physics - Theory · Physics 2009-11-10 Sarah E. Shandera

We study the slow-roll inflationary dynamics in a self-gravitating induced gravity braneworld model with bulk cosmological constant. For E \gg M_{5}^{3}/M^{2}_{2} we find important corrections to the four-dimensional Friedmann equation…

General Relativity and Quantum Cosmology · Physics 2009-11-10 E. Papantonopoulos , V. Zamarias

We present a new type of brane inflation motivated by multi-kink solitonic solutions of a scalar field in five dimensions. In the thin brane limit, we analyze a non-static configuration in which the distance between two parallel domain…

High Energy Physics - Phenomenology · Physics 2014-11-20 Kevin T. Engel

The unwinding inflation mechanism is studied in a type IIB flux compactification where all moduli are stabilized using flux, non-perturbative effects, and the leading alpha' corrections of the large volume scenario. We consider the…

High Energy Physics - Theory · Physics 2017-12-14 Juan Diaz Dorronsoro , Marjorie Schillo

We study models of inflation where the inflaton corresponds to a flat direction in field space and its mass term is generated by gravity mediated soft supersymmetry breaking at high scale. Assuming the inflaton to have non negligible…

High Energy Physics - Phenomenology · Physics 2007-05-23 Laura Covi

We consider an inflationary scenario where the rate of inflaton roll defined by $\ddot\phi/H\dot \phi$ remains constant. The rate of roll is small for slow-roll inflation, while a generic rate of roll leads to the interesting case of…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-09 Hayato Motohashi , Alexei A. Starobinsky , Jun'ichi Yokoyama

We calculate the power spectrum, spectral index, and running spectral index for the RS-II brane inflation in the high-energy regime using the slow-roll expansion. There exist several modifications. As an example, we take the power-law…

High Energy Physics - Theory · Physics 2009-11-10 Kyung Hee Kim , Hyung Won Lee , Yun Soo Myung

We present a detailed systematics for comparing warped brane inflation with the observations, incorporating the effects of both moduli stabilization and ultraviolet bulk physics. We explicitly construct an example of the inflaton potential…

High Energy Physics - Theory · Physics 2009-09-24 Heng-Yu Chen , Jinn-Ouk Gong

Warped braneworld models has the potential to provide a plausible resolution to the gauge hierarchy problem but at the cost of introduction of an additional field, namely the inter-brane separation or, the radion field. Providing an…

High Energy Physics - Theory · Physics 2019-01-23 Indrani Banerjee , Sumanta Chakraborty , Soumitra SenGupta

We study the evolution of universe with a single scalar field of constant potential minimally coupled to gravity in the brane world cosmology.We find an exact inflationary solution which is not in slow roll.We discuss the limiting cases of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 M. Sami

In this paper we quantise scalar perturbations in a Randall-Sundrum-type model of inflation where the inflaton field is confined to a single brane embedded in five-dimensional anti-de Sitter space-time. In the high energy regime,…

High Energy Physics - Theory · Physics 2010-10-27 Kazuya Koyama , Andrew Mennim , V. A. Rubakov , David Wands , Takashi Hiramatsu

In hybrid inflation models, typically only a tiny fraction of possible initial conditions give rise to successful inflation, even if one assumes spatial homogeneity. We analyze some possible solutions to this initial conditions problem,…

Astrophysics · Physics 2009-10-31 Luis E Mendes , Andrew R Liddle

Warm inflationary dynamics is shown to satisfy both the slow-roll and density perturbation constraints for $m_{\phi} \gg H$ or equivalently $\eta \gg 1$ and for inflaton field amplitudes much below the Planck scale, $<\phi > < m_{pl}$. I…

High Energy Physics - Phenomenology · Physics 2007-05-23 Arjun Berera

Spectrum of density perturbations in the Universe generated from quantum-gravitational fluctuations in slow-roll-over inflationary scenarios with the Brans-Dicke gravity is calculated. It is shown that after inflation the isocurvature mode…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Alexei A. Starobinsky , Jun'ichi Yokoyama

In the literature, many warm inflationary models are formulated. In this piece of work, a warm inflationary model in the braneworld scenario is studied, considering constant and variable dissipation coefficients. Performance of the model…

General Relativity and Quantum Cosmology · Physics 2025-12-11 Sabina Yeasmin , Atri Deshamukhya