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We consider the effects of entanglement in the initial quantum state of scalar and tensor fluctuations during inflation. We allow the gauge-invariant scalar and tensor fluctuations to be entangled in the initial state and compute…

High Energy Physics - Theory · Physics 2017-01-13 Nadia Bolis , Andreas Albrecht , R. Holman

In this article, we do a thorough investigation of the competency of the forthcoming Cosmic Microwave Background (CMB) and Galaxy surveys in probing the features in the primordial power spectrum. Primordial features are specific…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-01 Debabrata Chandra , Supratik Pal

We present a complete method for the initialisation and extraction of first-order inflationary tensor perturbations for fully relativistic simulations which incorporate gravitational back-reaction. We outline a correspondence between the…

General Relativity and Quantum Cosmology · Physics 2026-01-22 Ericka Florio , E. Paul S. Shellard

We explore extensions of hybrid inflationary models in the context of supersymmetric D-term inflation. We point out that a large variety of inflationary scenarios can be encountered when the field content is extended. It is not only…

High Energy Physics - Phenomenology · Physics 2008-11-26 Francis Bernardeau , Tristan Brunier

We consider the possibility that the primordial curvature perturbation was generated through the curvaton mechanism from a scalar field with an electric charge, or precisely the Standard Model U(1) weak hypercharge. This links the dynamics…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-05 Michela D'Onofrio , Rose N. Lerner , Arttu Rajantie

We analytically compute the power spectrum of primordial curvature perturbations in Type III hilltop inflation models under the slow-roll approximation. The model parameters are constrained using current Cosmic Microwave Background (CMB)…

General Relativity and Quantum Cosmology · Physics 2024-11-28 Chia-Min Lin , Harish Dhananjay Nalla , Chen-Pin Yeh , Da-Shin Lee

A detection of primordial non-Gaussianity could transform our understanding of the fundamental theory of inflation. The precision promised by upcoming CMB and large-scale structure surveys raises a natural question: if a detection given a…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-04 Joyce Byun , Rachel Bean

We show that a conformal-invariance violating coupling of the inflaton to electromagnetism produces a cross correlation between curvature fluctuations and a spectrum of primordial magnetic fields. According to this model, in the case of…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Leonardo Motta , Robert R. Caldwell

The linear and quadratic perturbations for a scalar-tensor model with non-minimal coupling to curvature, coupling to the Gauss-Bonnet invariant and non-minimal kinetic coupling to the Einstein tensor are developed. The quadratic action for…

General Relativity and Quantum Cosmology · Physics 2019-09-24 L. N. Granda , D. F. Jimenez

In this article we discuss the role of current and future CMB measurements in pinning down the model of inflation responsible for the generation of primordial curvature perturbations. By considering a parameterization of the effective field…

High Energy Physics - Theory · Physics 2014-10-03 Rhiannon Gwyn , Gonzalo A. Palma , Mairi Sakellariadou , Spyros Sypsas

Cosmic inflation provides a mechanism for generating the early density perturbations that seeded the large-scale structures we see today. Primordial non-Gaussianity is among the most promising of few observational tests of physics at this…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-10 Marilena LoVerde , Simone Ferraro , Kendrick M. Smith

We investigate an inflationary model of the universe based on the assumption that space-time is noncommutative in the very early universe. We analyze the effects of space-time noncommutativity on the quantum fluctuations of an inflaton…

High Energy Physics - Theory · Physics 2010-04-05 Masafumi Fukuma , Yuji Kono , Akitsugu Miwa

We present the first attempt to use a combination of CMB, LIGO, and PPTA data to constrain both the tilt and the running of primordial tensor power spectrum through constraints on the gravitational wave energy density generated in the early…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 P. Daniel Meerburg , Renée Hložek , Boryana Hadzhiyska , Joel Meyers

We study the amplitude and spectral tilt of density perturbations in the simplest hybrid inflation models. We give an exact expression for the amplitude of quantum fluctuations on all scales in the limit where we can neglect the…

Astrophysics · Physics 2009-06-19 Juan Garcia-Bellido , David Wands

In contrast to the inflaton's case, the curvature perturbations due to the curvaton field depend strongly on the evolution of the curvaton before its decay. We study in detail the dynamics of the curvaton evolution during and after…

High Energy Physics - Phenomenology · Physics 2008-11-26 Konstantinos Dimopoulos , George Lazarides , David Lyth , Roberto Ruiz de Austri

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

Current measurements of the temperature and polarization anisotropy power spectra of the Cosmic Microwave Background (CMB) seem to indicate that the naive expectation for the slow-roll hierarchy within the most simple inflationary paradigm…

Cosmology and Nongalactic Astrophysics · Physics 2020-12-10 Stefano Gariazzo , Olga Mena , Victor Miralles , Héctor Ramírez , Lotfi Boubekeur

Enormous information about interactions is contained in the non-Gaussianities of the primordial curvature perturbations, which are essential to break the degeneracy of inflationary models. We study the primordial bispectra for G-inflation…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-21 Fengge Zhang , Yungui Gong , Jiong Lin , Yizhou Lu , Zhu Yi

Constraining the inflationary epoch is one of the aims of modern cosmology. In order to fully exploit current and future small-scale observations, it is necessary to devise tools to directly relate them to the early universes dynamics. We…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-23 Gabriele Franciolini , Alfredo Urbano

In the inflationary cosmology it occurs frequently that the inflaton field is trapped in a local, transient minimum with non-zero vacuum energy. The difficulty regarding the curvature perturbation produced during such a stage is that…

Astrophysics · Physics 2009-06-23 Jinn-Ouk Gong , Misao Sasaki
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