English
Related papers

Related papers: Second-Order Cosmological Perturbations from Infla…

200 papers

The scalar and tensor fluctuations generated during inflation can be correlated, if arising from the same underlying mechanism. In this paper we investigate such correlation in the model of axion inflation, where the rolling inflaton…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-08 Sofia P. Corbà , Lorenzo Sorbo

Several recent proposals to embed inflation into high-energy physics rely on inflationary dynamics characterized by a strongly non-geodesic motion in negatively curved field space. This naturally leads to a transient instability of…

High Energy Physics - Theory · Physics 2019-11-20 Jacopo Fumagalli , Sebastian Garcia-Saenz , Lucas Pinol , Sébastien Renaux-Petel , John Ronayne

We study higher curvature corrections to the scalar spectral index, the tensor spectral index, the tensor-to-scalar ratio, and the polarization of gravitational waves. We find that the higher curvature corrections can not be negligible in…

Astrophysics · Physics 2011-07-13 Masaki Satoh , Jiro Soda

After introducing gauge-invariant cosmological perturbation theory we give an improved set of governing equations for multiple fluids including energy transfer. Having defined adiabatic and entropic perturbations we derive the…

Astrophysics · Physics 2007-05-23 Karim A. Malik

We study an inflationary scenario where thermal inflation is followed by fast-roll inflation. This is a rather generic possibility based on the effective potentials of spontaneous symmetry breaking in the context of particle physics models.…

High Energy Physics - Phenomenology · Physics 2008-11-26 Jinn-Ouk Gong

This article investigates the non-linear evolution of cosmological perturbations on sub-Hubble scales in order to evaluate the unavoidable deviations from Gaussianity that arise from the non-linear dynamics. It shows that the dominant…

Astrophysics · Physics 2009-02-23 Cyril Pitrou , Jean-Philippe Uzan , Francis Bernardeau

We study the inflationary gravitational wave background induced by Abelian gauge fields generated by non-minimal kinetic and axial couplings to the inflaton. We show that, up to slow-roll corrections, for coupling functions that share the…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-20 Martin Teuscher , Ruth Durrer , Killian Martineau , Aurélien Barrau

In principle, the tensor metric (gravity-wave) perturbations that arise in inflationary models can, beyond probing the underlying inflationary model, provide information about the Universe: ionization history, presence of a cosmological…

Astrophysics · Physics 2009-08-18 Michael S. Turner , Martin White , James E. Lidsey

It is well known that processes of first order phase transitions may have occurred in the inflationary era. If one or more occurred well before the end of inflation, the nucleated bubbles are stretched to large scales and the primordial…

Astrophysics · Physics 2009-10-30 Carlo Baccigalupi

A brief account is given of large-scale structure modelling based on the assumption that the initial perturbations arise from inflation. A recap is made of the implications of inflation for large-scale structure; under the widely applicable…

Astrophysics · Physics 2007-05-23 Andrew R Liddle

The full set of cosmological observables coming from linear scalar and tensor perturbations of loop quantum cosmology is computed in the presence of inverse-volume corrections. Background inflationary solutions are found at linear order in…

General Relativity and Quantum Cosmology · Physics 2011-03-28 Martin Bojowald , Gianluca Calcagni

We study the metric perturbations produced during inflation in models with two scalar fields evolving simultaneously. In particular, we emphasize how the large-scale curvature perturbation $\zeta$ on fixed energy density hypersurfaces may…

Astrophysics · Physics 2016-08-24 Juan Garcia-Bellido , David Wands

We compute the primordial trispectrum for curvature perturbations produced during cosmic inflation in models with standard kinetic terms, when the initial quantum state is not necessarily the vacuum state. The presence of initial…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Ivan Agullo , Jose Navarro-Salas , Leonard Parker

We calculate how primordial anisotropies in the background space-time affect the evolution of cosmological perturbations for bouncing alternatives to inflation, like ekpyrosis and the matter bounce scenario. We find that the leading order…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-18 Ivan Agullo , Javier Olmedo , Edward Wilson-Ewing

An important prediction of inflation is the production of a primordial stochastic gravitational wave background. Observing this background is challenging due to the weakness of the signal and the simultaneous presence of an astrophysical…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-18 Sofia P. Corbà

Bayesian model comparison penalizes models with more free parameters that are allowed to vary over a wide range, and thus offers the most robust method to decide whether some given data require new parameters. In this paper, we ask a simple…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-28 Tommaso Giannantonio , Eiichiro Komatsu

We consider the impact of thermal inflation -- a short, secondary period of inflation that can arise in supersymmetric scenarios -- on the stochastic gravitational wave background. We show that while the primordial inflationary…

Astrophysics · Physics 2009-06-23 Richard Easther , John T. Giblin , Eugene A. Lim , Wan-Il Park , Ewan D. Stewart

Long-short mode coupling during inflation, encoded in the squeezed bispectrum of curvature perturbations, induces a dependence of the local, small-scale power spectrum on long-wavelength perturbations, leading to a scale-dependent halo…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-19 Giovanni Cabass , Enrico Pajer , Fabian Schmidt

We study quantum fluctuations of a free massless scalar field during inflation in the presence of a point, line, or plane defect such as a black hole, cosmic string, or domain wall, using a perturbative expansion in powers of small defect…

High Energy Physics - Theory · Physics 2015-06-19 Hing-Tong Cho , Kin-Wang Ng , I-Chin Wang

The inflationary potential and its derivatives determine the spectrum of scalar and tensor metric perturbations that arise from quantum fluctuations during inflation. The CBR anisotropy offers a promising means of determining the spectra of…

Astrophysics · Physics 2009-08-18 Michael Turner , Martin White
‹ Prev 1 8 9 10 Next ›