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相关论文: On the Problem of Predicting Inflationary Perturba…

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We carry out numerical investigations of the perturbations in Nflation models where the mass spectrum is generated by random matrix theory. The tensor-to-scalar ratio and non-gaussianity are already known to take the single-field values,…

天体物理学 · 物理学 2008-12-18 Soo A Kim , 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…

高能物理 - 唯象学 · 物理学 2007-05-23 Arjun Berera

This paper considers warm inflation as an interesting application of multi-field inflation. Delta-N formalism is used for the calculation of the evolution of the curvature perturbations during warm inflation. Although the perturbations…

宇宙学与河外天体物理 · 物理学 2010-04-28 Tomohiro Matsuda

The inflationary paradigm is the most successful model that explains the observed spectrum of primordial perturbations. However, the precise emergence of such inhomogeneities and the quantum-to-classical transition of the perturbations has…

广义相对论与量子宇宙学 · 物理学 2016-01-26 Gabriel Leon , Gabriel R. Bengochea

A long-standing problem in primordial cosmology is to understand the precise relation between the stochastic formalism and standard perturbation theory for light scalar fields in inflationary spacetimes. A complete correspondence between…

高能物理 - 理论 · 物理学 2026-02-10 Gonzalo A. Palma , Spyros Sypsas

We here investigate bulk-viscosity driven quasi de-Sitter inflation, that is, the period of accelerated expansion in the early universe during which $-\dot{H}\ll H^2$, with $H(t)$ being the Hubble expansion rate. We do so in the framework…

广义相对论与量子宇宙学 · 物理学 2024-02-21 Sayantani Lahiri , Luciano Rezzolla

A perturbative strategy for inflation described by two-inflaton fields is developed using a mathematical analogy with the renormalization-group. Two small quantities, $\alpha$ and $\lambda$, corresponding to standard slow-roll parameters…

高能物理 - 理论 · 物理学 2025-06-10 Bohdan Grzadkowski , Marco Piva

A gauge-independent, invariant theory of linear scalar perturbations of inflation and gravitational fields has been created. This invariant theory allows one to compare gauges used in the work of other researchers and to find the…

广义相对论与量子宇宙学 · 物理学 2007-05-23 O. Lalakulich , L. Marochnik , G. Vereshkov

The present paper tries to answer the question: Can a de Sitter phase in presence of radiation be a competitor of the standard inflationary paradigm for the early universe? This kind of a de Sitter phase can exist in cosmological models…

广义相对论与量子宇宙学 · 物理学 2022-08-03 Kaushik Bhattacharya , Anirban Chatterjee , Saddam Hussain

The emergence of time in the matter-gravity system is addressed within the context of the inflationary paradigm. A quantum minisuperspace-homogeneous minimally coupled inflaton system is studied with suitable initial conditions leading to…

广义相对论与量子宇宙学 · 物理学 2008-11-26 A. Tronconi , G. P. Vacca , G. Venturi

In this article we present an alternative formalism for the inflationary phenomenology of rescaled Einstein-Gauss-Bonnet models which are in agreement with the GW170817 event. By constraining the propagation velocity of primordial tensor…

广义相对论与量子宇宙学 · 物理学 2023-08-01 S. D. Odintsov , V. K. Oikonomou , F. P. Fronimos

We discuss a new mechanism which can be responsible for the origin of the primordial perturbation in inflationary models, the inhomogeneous DBI reheating scenario. Light DBI fields fluctuate during inflation, and finally create the density…

高能物理 - 理论 · 物理学 2015-03-17 Sheng Li

We use a numerical code to compute the density perturbations generated during an inflationary epoch which includes a spontaneous symmetry breaking phase transition. A sharp step in the inflaton potential generates $k$ dependent oscillations…

天体物理学 · 物理学 2009-11-06 Jennifer Adams , Bevan Cresswell , Richard Easther

In this work, we investigate inflationary cosmology using scalar field theory deformed by the generalized uncertainty principle (GUP) containing a linear momentum term. Apart from being consistent with the existence of a minimum measurable…

广义相对论与量子宇宙学 · 物理学 2015-12-02 Ahmed Farag Ali , Mir Faizal , Mohammed M. Khalil

The Starobinsky model predicts a primordial inflation period without the presence of an inflaton field. The modified version of this model predicts a simple time dependence for the Hubble parameter $H(t)$, which decreases slowly between the…

天体物理学 · 物理学 2015-06-24 Reuven Opher , Ana Pelinson

We consider a quantum corrected inflation scenario driven by a generic GUT or Standard Model type particle model whose scalar field playing the role of an inflaton has a strong non-minimal coupling to gravity. We show that currently widely…

高能物理 - 唯象学 · 物理学 2009-01-06 A. O. Barvinsky , A. Yu. Kamenshchik , A. A. Starobinsky

We analyse the evolution of the reduced density matrix of inflationary perturbations, coupled to a heavy entropic field via the leading-order term within the Effective Field Theory of Inflation, for two nearly de Sitter backgrounds. We…

高能物理 - 理论 · 物理学 2024-11-14 Suddhasattwa Brahma , Jaime Calderón-Figueroa , Xiancong Luo , David Seery

We describe how non-minimal coupling term between the Higgs boson and gravity can lead to the chaotic inflation in the Standard Model without introduction of any additional degrees of freedom. Produced cosmological perturbations are…

高能物理 - 唯象学 · 物理学 2008-05-16 F. L. Bezrukov

We discuss how primordial non-Gaussianity of the curvature perturbation helps to constrain models of the early universe. Observations are consistent with Gaussian initial conditions, compatible with the predictions of the simplest models of…

宇宙学与河外天体物理 · 物理学 2014-11-26 Christian T. Byrnes

A class of non-canonical inflationary models is identified, where the leading-order contribution to the non-Gaussianity of the curvature perturbation is determined by the sound speed of the fluctuations in the inflaton field. Included in…

高能物理 - 理论 · 物理学 2008-11-26 Ian Huston , James E. Lidsey , Steven Thomas , John Ward