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We investigate thermal inflation in double-screen entropic cosmology. We find that its realization is general, resulting from the system evolution from non-equilibrium to equilibrium. Furthermore, going beyond the background evolution, we…

High Energy Physics - Theory · Physics 2011-05-26 Yi-Fu Cai , Emmanuel N. Saridakis

The effect of including a Gauss-Bonnet contribution in the bulk action is investigated within the context of the steep inflationary scenario. When inflation is driven by an exponential inflaton field, this Gauss-Bonnet term allows the…

Astrophysics · Physics 2009-11-07 James E. Lidsey , N. J. Nunes

We present a holographic description of four-dimensional single-scalar inflationary universes in terms of a three-dimensional quantum field theory. The holographic description correctly reproduces standard inflationary predictions in their…

High Energy Physics - Theory · Physics 2010-06-11 Paul McFadden , Kostas Skenderis

We investigate the non-Gaussianity of primordial cosmological perturbations within our recently proposed holographic description of inflationary universes. We derive a holographic formula that determines the bispectrum of cosmological…

High Energy Physics - Theory · Physics 2011-05-16 Paul McFadden , Kostas Skenderis

In this paper we present the study of the scalar cosmological perturbations of a single field inflationary model up to first order in deviation. The Christoffel symbols and the tensorial quantities are calculated explicitly in function of…

General Relativity and Quantum Cosmology · Physics 2020-07-10 Truman Tapia , Clara Rojas

We consider cosmological inflation generated by a scalar field slowly rolling off from a de Sitter maximum of its potential. The models belong to the class of hilltop models and represent the most general model of this kind in which the…

General Relativity and Quantum Cosmology · Physics 2016-09-05 Mariano Cadoni , Edgardo Franzin , Salvatore Mignemi

We study primordial perturbations from hyperinflation, proposed recently and based on a hyperbolic field-space. In the previous work, it was shown that the field-space angular momentum supported by the negative curvature modifies the…

High Energy Physics - Theory · Physics 2017-12-08 Shuntaro Mizuno , Shinji Mukohyama

An alternative scenario about the phenomenology of primordial Universe is k-inflation. According to this concept, inflation can be achieved by nonstandard kinetic term of scalar field, namely the inflaton. In this project we focus on…

General Relativity and Quantum Cosmology · Physics 2021-12-01 F. P. Fronimos , S. A. Venikoudis

The possibility that the scale-invariant inflationary spectrum may be modified due to the hidden assumptions about the Planck scale physics -- dubbed as trans-Planckian inflation -- has received considerable attention. To mimic the possible…

High Energy Physics - Theory · Physics 2009-11-11 S. Shankaranarayanan , Musongela Lubo

The string $\alpha^\prime$-correction to the usual Einstein action comprises a Gauss-Bonnet integrand multiplied by non-trivial functions of the modulus field $\chi$ and/or the dilaton field $\phi$. We discuss how the presence of such terms…

High Energy Physics - Theory · Physics 2007-05-23 Ishwaree P Neupane

The Dirac-Born-Infeld (DBI) action has been widely studied as an interesting example of a model of k-inflation in which the sound speed of the cosmological perturbations differs from unity. In this article we consider a scalar-tensor theory…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Carsten van de Bruck , David F. Mota , Joel M. Weller

We study the primordial bispectrum of curvature perturbation in the uniform- density slicing generated by the interaction between the inflaton and isotropic background gauge fields. We derive the action up to cubic order in perturbation and…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-05 Hiroyuki Funakoshi , Kei Yamamoto

Observational consequences of inflationary cosmology in the holographic dual of the Randall-Sundrum type II braneworld scenario, as motivated by the AdS/CFT correspondence, are investigated. High energy corrections to the standard…

Astrophysics · Physics 2008-04-22 James E. Lidsey , David Seery

We investigate the possibility of the inflation driven by a Lorentz invariant non-standard spinor field. As these spinors are having dominant interaction via gravitational field only, they are considered as \emph{Dark Spinors}. We study how…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-20 Abhishek Basak , Jitesh R. Bhatt

We analyze the effects of the holographic dark energy model in a single field slow-roll inflation, taking into account both the holographic and the dark radiation components. In particular, we obtain the background evolution and compute the…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-07 Paola C. M. Delgado , Alexander Ganz , Chunshan Lin

We study the implications of deformed quantum algebras for the generation of primordial perturbations from slow-roll inflation. Specifically, we assume that the quantum commutator of the inflaton's amplitude and momentum in Fourier space…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Andrew C. Day , Iain A. Brown , Sanjeev S. Seahra

The holographic entropy bound is used to estimate the quantum-gravitational discreteness of inflationary perturbations. In the context of scalar inflaton perturbations produced during standard slow-roll inflation, but assuming that…

Astrophysics · Physics 2009-11-07 Craig J. Hogan

We investigate observational constraints on inflationary parameters in the context of an holographic cosmology with an induced gravity correction. We consider two situations where a universe is firstly filled with a scalar field and…

High Energy Physics - Theory · Physics 2020-04-21 Aatifa Bargach , Farida Bargach , Ahmed Errahmani , Taoufik Ouali

Inflationary cosmology provides a natural mechanism for the generation of primordial perturbations which seed the formation of observed cosmic structure and lead to specific signals of anisotropy in the cosmic microwave background…

Astrophysics · Physics 2011-07-19 Salman Habib , Andreas Heinen , Katrin Heitmann , Gerard Jungman

We derive a Higgs inflationary model in the context of holographic cosmology, where we consider a universe filled with a Higgs field non-minimally coupled to gravity in a slow-roll regime. The amplitude of density (scalar) perturbations is…

General Relativity and Quantum Cosmology · Physics 2021-01-28 Aatifa Bargach , Farida Bargach , Mariam Bouhmadi-López , Taoufik Ouali