中文
相关论文

相关论文: Inflationary predictions at small gamma

200 篇论文

In this paper we investigate the asymptotic dynamics of inflationary cosmological models that are based in scalar-tensor theories of gravity. Our main aim is to explore the global structure of the phase space in the framework of…

广义相对论与量子宇宙学 · 物理学 2020-05-20 Israel Quiros , Tame Gonzalez , Roberto De Arcia , Ricardo García-Salcedo , Ulises Nucamendi , Joel F. Saavedra

We study constant roll inflation systematically. This is a regime, in which the slow roll approximation can be violated. It has long been thought that this approximation is necessary for agreement with observations. However, recently it was…

高能物理 - 理论 · 物理学 2018-02-21 Lilia Anguelova , Peter Suranyi , L. C. Rohana Wijewardhana

Canonical models of single-field, slow-roll inflation do not lead to appreciable non-Gaussianity, unless derivative interactions of the inflaton become uncontrollably large. We propose a novel slow-roll scenario where scalar perturbations…

高能物理 - 理论 · 物理学 2016-05-25 David Pirtskhalava , Luca Santoni , Enrico Trincherini , Filippo Vernizzi

Slow roll reconstruction is derived from the Hamilton-Jacobi formulation of inflationary dynamics. It automatically includes information from sub-leading terms in slow roll, and facilitatesthe inclusion of priors based on the duration on…

天体物理学 · 物理学 2009-06-23 Peter Adshead , Richard Easther

We study the slow-roll inflation models, where the inflaton slow-rolls along a trajectory whose orthogonal directions are lifted by potentials with masses of order the Hubble parameter. In these models large non-Gaussianities can be…

宇宙学与河外天体物理 · 物理学 2010-04-06 Xingang Chen , Yi Wang

An inflationary model can be constrained by non-gaussian statistics as a parameter in the LSS (Large Scale Structure) distribution, and in the radiation of CMB (Cosmic Microwave Background) fluctuating temperature. Data on the CMB from…

广义相对论与量子宇宙学 · 物理学 2025-12-11 A. Agung , U. Sambiri , G. Hikmawan , F. P. Zen

We perform a thorough computation of the one-loop corrections from both scalar and tensor degrees of freedom to the power spectrum of curvature fluctuations for non-canonical Lagrangians in single-field inflation. We consider models…

宇宙学与河外天体物理 · 物理学 2011-01-27 Nicola Bartolo , Emanuela Dimastrogiovanni , Alberto Vallinotto

We compute the non-Gaussianities that arise in single field, slow roll inflationary models arising from arbitrary homogeneous initial states, as well as subleading contributions to the power spectrum. Non Bunch-Davies vacuum initial states…

宇宙学与河外天体物理 · 物理学 2015-05-12 Sina Bahrami , Éanna É. Flanagan

We derive a generalized expressions for the scalar power spectrum and the observational parameters of inflation (the scalar spectral index $n_{\rm s}$ and the tensor-to-scalar ratio $r$) for several single field scalar models minimally…

广义相对论与量子宇宙学 · 物理学 2024-09-25 Marko Stojanovic , Dragoljub D. Dimitrijevic , Milan Milosevic

We investigate the possibility of obtaining inflationary solutions of the slow roll type from a low energy Lagrangian coming from superstrings. The advantage of such an approach is that in these theories the scalar potential has only one…

高能物理 - 唯象学 · 物理学 2009-10-28 A. De la Macorra , S. Lola

In single-field, slow-roll inflationary models, scalar and tensorial (Gaussian) perturbations are both characterized by a zero mean and a non-zero variance. In position space, the corresponding variance of those fields diverges in the…

广义相对论与量子宇宙学 · 物理学 2014-11-20 I. Agullo , J. Navarro-Salas , Gonzalo J. Olmo , Leonard Parker

We study a single field inflationary model modified by a non-minimal coupling term between the Ricci scalar $R$ and the scalar field $\varphi$ in the context of constant-roll inflation. The first-order formalism is used to analyse the…

广义相对论与量子宇宙学 · 物理学 2021-08-11 Mehdi Shokri , Jafar Sadeghi , Mohammad Reza Setare , Salvatore Capozziello

We investigate non-Gaussianity in general single field models without assuming slow-roll conditions or the exact scale-invariance of the scalar power spectrum. The models considered include general single field inflation (e.g. DBI and…

宇宙学与河外天体物理 · 物理学 2011-05-13 Johannes Noller , Joao Magueijo

Slow-roll inflation is studied in theories where the inflaton field is conformally coupled to the Ricci scalar. In particular, the case of Higgs field inflation in the context of the noncommutative spectral action is analyzed. It is shown…

高能物理 - 理论 · 物理学 2010-08-31 Michel Buck , Malcolm Fairbairn , Mairi Sakellariadou

We examine the covariant properties of generalized models of two-field inflation, with non-canonical kinetic terms and a possibly non-trivial field metric. We demonstrate that kinetic-term derivatives and covariant field derivatives do…

宇宙学与河外天体物理 · 物理学 2014-07-28 Eleftheria Tzavara , Shuntaro Mizuno , Bartjan van Tent

We present constraints on canonical single-field inflation derived from WMAP five year, ACBAR, QUAD, BICEP data combined with the halo power spectrum from SDSS LRG7. Models with a non-scale-invariant spectrum and a red tilt n_s < 1 are now…

宇宙学与河外天体物理 · 物理学 2010-04-30 Fabio Finelli , Jan Hamann , Samuel M. Leach , Julien Lesgourgues

We present constraints on how far single field inflation may depart from the familiar slow-roll paradigm. Considering a fast-roll regime while requiring a (near)-scale-invariant power spectrum introduces large self-interactions for the…

宇宙学与河外天体物理 · 物理学 2012-09-12 Johannes Noller

We perform a general study of the primordial scalar non-Gaussianities in multi-field inflationary models in Einstein gravity. We consider models governed by a Lagrangian which is a general function of the scalar fields and their first…

天体物理学 · 物理学 2009-06-23 Xian Gao

Many statistics available to constrain non-Gaussianity from inflation are simplest to use under the assumption that the curvature correlation functions are hierarchical. That is, if the n-point function is proportional to the (n-1) power of…

天体物理学 · 物理学 2010-04-30 Sarah Shandera

In this article we analyze the reconstruction of inflation in the framework of a non-canonical theory. In this sense, we study the viability of reconstructing the background variables assuming a non-lineal kinetic term given by…

宇宙学与河外天体物理 · 物理学 2024-04-15 Ramon Herrera , Carlos Rios