English
Related papers

Related papers: Is power-law inflation really attractive?

200 papers

Everlasting inflation has far-reaching implications for cosmology and the standing of self-localizing inferences made by observers, which have been subjects of renewed interest in light of the growing acceptance of theory landscapes and the…

General Relativity and Quantum Cosmology · Physics 2021-12-28 Ross N Greenwood , Anthony Aguirre

We propose a new mechanism to generate primordial curvature perturbations, based on the resonant production of particles during inflation. It is known that this phenomenon can trap the inflaton for a fraction of e-fold. This effect is…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-17 David Langlois , Lorenzo Sorbo

We study how higher-order gravity affects Higgs inflation in the Palatini formulation. We first review the metric and Palatini formulations in comparative manner and discuss their differences. Next cosmic inflation driven by a scalar field…

General Relativity and Quantum Cosmology · Physics 2021-06-28 Jaakko Annala

In this work we determine the power spectrum of the gravitational potential of the primordial fluctuations for an inflationary model whose \emph{inflaton} is a non-canonical scalar field of the tachyon-type. The respective background field…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Rudinei C. de Souza , Gilberto M. Kremer

It was recently proposed that five-dimensional inflation can relate the causal size of the observable universe to the present weakness of gravitational interactions by blowing up an extra compact dimension from the microscopic fundamental…

High Energy Physics - Phenomenology · Physics 2024-04-30 Ignatios Antoniadis , Jules Cunat , Anthony Guillen

We explore the correlations between correlation functions of the primordial curvature perturbation produced during inflation. We find that for general single field inflation, other than the source terms which depend on the model details,…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-02 Jinn-Ouk Gong , Koenraad Schalm , Gary Shiu

During inflation explicit perturbative computations of quantum field theories which contain massless, non-conformal fields exhibit secular effects that grow as powers of the logarithm of the inflationary scale factor. Starobinski\u{\i}'s…

Astrophysics · Physics 2009-11-10 R. P. Woodard

We consider an inflationary universe scenario with multiple stages of inflation. The primary inflation, which may start at the Planck epoch, is followed by secondary inflations, which include the cosmological inflation that causes the…

High Energy Physics - Phenomenology · Physics 2007-05-23 K. -I. Izawa

Inflationary cosmologies, regarded as dynamical systems, have rather simple asymptotic behavior, insofar as the cosmic baldness principle holds. Nevertheless, in the early stages of an inflationary process, the dynamical behavior may be…

General Relativity and Quantum Cosmology · Physics 2009-10-22 E. Calzetta , C. El Hasi

Conditions are obtained for the existence of a warm inflationary attractor in the system of equations describing an inflaton coupled to radiation. These conditions restrict the temperature dependence of the dissipative terms and the size of…

Astrophysics · Physics 2011-07-13 Ian G Moss , Chun Xiong

Particle creation during inflation is considered. It could be important for species whose interaction is of gravitational strength or weaker. A complete but economical formalism is given for spin-zero and spin-half particles, and the…

High Energy Physics - Phenomenology · Physics 2016-08-25 David H. Lyth , David Roberts

The inflationary and pre-inflationary evolution of scalar modes of cosmological perturbations in a closed universe is analyzed for a loop quantum cosmology model with an inflationary regime consistent with the constraints on inflation…

General Relativity and Quantum Cosmology · Physics 2024-11-26 Lucas M. V. Montese , Nelson Yokomizo

Three-forms can give rise to viable cosmological scenarios of inflation and dark energy with potentially observable signatures distinct from standard single scalar field models. In this study, the background dynamics and linear…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-19 Tomi S. Koivisto , Nelson J. Nunes

The single scalar field inflationary models that lead to scalar and tensor perturbation spectra with amplitudes varying in direct proportion to one another are reconstructed by solving the Stewart-Lyth inverse problem to next-to-leading…

Astrophysics · Physics 2009-11-07 C. A. Terrero-Escalante , James E. Lidsey , Alberto A. Garcia

Inflation can be parameterized by means of truncated flow equations. In this "horizon-flow" setup, generic results have been obtained, such as typical values for $r/(1-n_\mathrm{S})$. They are sometimes referred to as intrinsic features of…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-08 Vincent Vennin

We propose a new parametrization of the background equations of motion corresponding to (canonical) single-field models of inflation, which allows a better understanding of the general properties of the solutions and of the corresponding…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-05 L. Arturo Urena-Lopez

We present a generic inference method for inflation models from observational data by the usage of higher-order statistics of the curvature perturbation on uniform density hypersurfaces. This method is based on the calculation of the…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-25 Sebastian Dorn , Erandy Ramirez , Kerstin E. Kunze , Stefan Hofmann , Torsten A. Enßlin

We study the power spectrum of the mass density perturbations in an inflation scenario that includes thermal dissipation. We show that the condition on which the thermal fluctuations dominate the primordial density perturbations can easily…

Astrophysics · Physics 2009-10-31 Wolung Lee , Li-Zhi Fang

For the inflaton perturbations it is shown that the evolution of the difference between the spectral indices can be translated into information on the scale dependence of the tensor to scalar amplitudes ratio, $r$, and how the scalar field…

Astrophysics · Physics 2009-11-07 C. A. Terrero-Escalante

The effect of the initial condition of inflation on the power spectra of scalar and tensor perturbations is estimated assuming a slow-roll inflation model. By defining a more general initial state in inflation particular properties of the…

Astrophysics · Physics 2007-10-15 Shiro Hirai , Tomoyuki Takami