English
Related papers

Related papers: Non-Gaussianity in KKLMMT model

200 papers

We describe string production after angled brane inflation. First, we point out that there was a discrepancy in previous discussions. The expected tension of the cosmic string calculated from the four-dimensional effective Lagrangian did…

High Energy Physics - Phenomenology · Physics 2009-11-10 Tomohiro Matsuda

We investigate non-Gaussianity in general multiple-field inflation using the formalism we developed in earlier papers. We use a perturbative expansion of the non-linear equations to calculate the three-point correlator of the curvature…

Astrophysics · Physics 2009-11-13 G. I. Rigopoulos , E. P. S. Shellard , B. J. W. van Tent

We consider a cosmological scenario within the KKLT framework for moduli stabilization in string theory. The universal open string tachyon of decaying non-BPS D-brane configurations is proposed to drive eternal topological inflation.…

High Energy Physics - Theory · Physics 2009-11-11 Daniel Cremades , Fernando Quevedo , Aninda Sinha

We show that brane inflation is very sensitive to tiny sharp features in extra dimensions, including those in the potential and in the warp factor. This can show up as observational signatures in the power spectrum and/or non-Gaussianities…

High Energy Physics - Theory · Physics 2011-03-04 Rachel Bean , Xingang Chen , Girma Hailu , S. -H. Henry Tye , Jiajun Xu

We study the non-Gaussianity in the simplest infrared (IR) model of the DBI inflation. We show that the non-Gaussianity in such a model is compatible with the current observational bound, and is within the sensitivity of future experiments.…

Astrophysics · Physics 2009-11-13 Xingang Chen

We consider inflationary cosmology in the context of string compactifications with multiple throats. In scenarios where the warping differs significantly between throats, string and Kaluza-Klein physics can generate potentially observable…

High Energy Physics - Theory · Physics 2008-11-26 Andrew R. Frey , Anupam Mazumdar , Robert Myers

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

A long period of inflation can be triggered when the inflaton is held up on the top of a steep potential by the infrared end of a warped space. We first study the field theory description of such a model. We then embed it in the flux…

High Energy Physics - Theory · Physics 2009-11-11 Xingang Chen

The eta problem is one of the most significant obstacles to building a successful inflationary model in string theory. Planck mass suppressed corrections to the inflaton potential generally lead to inflaton masses of order the Hubble scale…

High Energy Physics - Theory · Physics 2010-01-15 Damien A. Easson , Ruth Gregory

In the noncommutative space-time the fine tuning in KKLMMT model can be significantly released and a nice running of spectral index fitting the WMAP three year data can be achieved. The fitting results show that the noncommutative mass…

Astrophysics · Physics 2009-11-11 Qing-Guo Huang

The evolution of slow--roll inflation in a five--dimensional brane world model with two boundary branes and bulk scalar field is studied. Assuming that the inflationary scale is below the brane tension, we can employ the moduli space…

Astrophysics · Physics 2009-11-10 P. R. Ashcroft , C. van de Bruck , A. -C. Davis

We consider the interactions between Dp-branes intersecting at an arbitrary number of angles in the context of type II string theory. For cosmology purposes we concentrate in the theory on R^{3,1} x T^6. Interpreting the distance between…

High Energy Physics - Theory · Physics 2009-11-07 M. Gomez-Reino , I. Zavala

We study a new framework for brane-antibrane inflation where moduli stabilisation relies purely on perturbative corrections to the effective action. This guarantees that the model does not suffer from the eta-problem. The inflationary…

We discuss sneutrino inflation in the brane-world scenario. We work in the Randall-Sundrum type II brane-world, generalized with the introduction of the Gauss-Bonnet term, a correction to the effective action in string theories. We find…

High Energy Physics - Phenomenology · Physics 2009-11-11 G. Panotopoulos

We investigate a static, cylindrically symmetric cosmic string on the brane without a perturbative approximation. We find there could be a (large) enhancement of the (effective) string tension when the energy density at the center of the…

High Energy Physics - Theory · Physics 2023-04-12 Chia-Min Lin

We examine how reheating occurs after brane-antibrane inflation in warped geometries, such as those which have recently been considered for Type IIB string vacua. We adopt the standard picture that the energy released by brane annihilation…

High Energy Physics - Theory · Physics 2008-11-26 N. Barnaby , C. P. Burgess , J. M. Cline

In arXiv:0908.4089, we have proposed a model where natural inflation is realized on a steep potential as a consequence of the interaction of the inflaton with gauge fields through an axion-like coupling. In the present work we study the…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Mohamed M. Anber , Lorenzo Sorbo

We study multi-field DBI inflation models with a waterfall phase transition. This transition happens for a D3 brane moving in the warped conifold if there is an instability along angular directions. The transition converts the angular…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-29 Taichi Kidani , Kazuya Koyama , Shuntaro Mizuno

Previous work on DBI inflation, which achieves inflation through the motion of a $D3$ brane as it moves through a warped throat compactification, has focused on the region far from the tip of the throat. Since reheating and other observable…

High Energy Physics - Theory · Physics 2009-11-11 Steven Kecskemeti , John Maiden , Gary Shiu , Bret Underwood

We discuss how Starobinsky-like inflation may emerge from dilaton dynamics in brane cosmology scenarios based on string theory, in which our universe is represented as a three-brane. The effective potential may acquire a constant term from…

High Energy Physics - Theory · Physics 2015-06-18 John Ellis , Nick E. Mavromatos , Dimitri V. Nanopoulos