Slow-roll parameters in braneworld cosmologies
نویسنده
چکیده
We present a general slow-roll formalism within braneworld-motivated cosmologies with nonstandard effective Friedmann equations. Full towers of parameters involving either the inflaton potential or the Hubble parameter are constructed and the dynamics of non-tachyonic and tachyonic fields are considered in detail; exact cosmological solutions and the inflationary attractor condition are provided. We compare scalar-driven and tachyon-driven accelerating eras through slow-roll correspondence and the observational imprint on early-universe structures.
منابع مشابه
Consistency equations in Randall-Sundrum cosmology: a test for braneworld inflation
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 assumptions, extrapolating next-order formulas from first-order calculations in the case of a de Sitter brane, we see that the degeneracy between standard and branewo...
متن کاملChaotic Inflation on the Brane with Induced Gravity
We study the slow-roll inflationary dynamics in a self-gravitating induced gravity braneworld model with bulk cosmological constant. For E ≫ M3 5 /M2 4 we find important corrections to the four-dimensional Friedmann equation which bring the standard chaotic inflationary scenario in closer agreement with recent observations. For M3 5 /M 2 P l ≪ E ≪ M3 5 /M2 4 we find five-dimensional corrections...
متن کاملNon-Gaussianity in braneworld and tachyon inflation
We calculate the bispectrum of single-field braneworld inflation, triggered by either an ordinary scalar field or a cosmological tachyon, by means of a gradient expansion of large-scale non-linear perturbations coupled to stochastic dynamics. The resulting effect is identical to that for single-field 4D standard inflation, the nonlinearity parameter being proportional to the scalar spectral ind...
متن کاملExactly Scale-Invariant Cosmological Perturbations From a Colliding Bubble Braneworld Universe
One of the aims of braneworld cosmology is to identify a ‘smoking gun’ for the existence of large extra dimensions by means of observations of the early universe. Braneworld cosmology has succeeded in reproducing the conventional cosmology at late times in a higher-dimensional context, but finding a unique observational signature has proved elusive. Here we demonstrate that the recently propose...
متن کاملOn Inflation Potentials in Randall-Sundrum Braneworld Model
We study the inflationary dynamics of the universe in the Randall-Sundrum typeII Braneworld model. We consider both an inverse-power law and exponential potentials and apply the Slow-Roll approximation in high energy limit to derive analytical expression of relevant inflationary quantities. An upper bound for the coupling constant was also obtained and a numerical value of perturbation spectrum...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2005