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Related papers: Anisotropic Inflation with General Potentials

200 papers

We study the imprints of anisotropic inflation on the CMB temperature fluctuations and polarizations. The statistical anisotropy stems not only from the direction dependence of curvature and tensor perturbations, but also from the cross…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-23 Masa-aki Watanabe , Sugumi Kanno , Jiro Soda

For icosahedral inflation, we compute the tensor modes' two-point function in the presence of higher derivative corrections, and show that in general this features anisotropies that are aligned with the underlying icosahedral structure. The…

High Energy Physics - Theory · Physics 2018-07-12 Jonghee Kang , Alberto Nicolis

We study inflation in a random multifield potential, using techniques developed by Marsh et al. The potential is a function of a large number of fields, and we choose parameters so that inflation only occurs in regions where the potential…

High Energy Physics - Theory · Physics 2016-08-02 Ben Freivogel , Roberto Gobbetti , Enrico Pajer , I-Sheng Yang

As opposed to Wald's cosmic no-hair theorem in general relativity, it is shown that the Horndeski theory (and its generalization) admits anisotropic inflationary attractors if the Lagrangian depends cubically on the second derivatives of…

General Relativity and Quantum Cosmology · Physics 2018-08-01 Hiroaki W. H. Tahara , Sakine Nishi , Tsutomu Kobayashi , Jun'ichi Yokoyama

Inflationary models can correlate small-scale density perturbations with the long-wavelength gravitational waves (GW) in the form of the Tensor-Scalar-Scalar (TSS) bispectrum. This correlation affects the mass-distribution in the Universe…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-28 Razieh Emami , Hassan Firouzjahi

Anisotropic inflation is an interesting model with an U(1) gauge field and it predicts the statistical anisotropy of the curvature perturbation characterized by a parameter $g_*$. However, we find that the background gauge field does not…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-14 Tomohiro Fujita , Ippei Obata

We study a generality of an inflationary scenario by integrating the Einstein equations numerically in a plane-symmetric spacetime. We consider the inhomogeneous spacetimes due to (i) localized gravitational waves with a positive…

General Relativity and Quantum Cosmology · Physics 2009-10-22 Hisa-aki SHINKAI , Kei-ichi MAEDA

For the original hybrid inflation model, we calculate the power spectrum of curvature perturbations generated during the waterfall, taking into account the contribution of entropic modes. We study the regime where the potential is very…

General Relativity and Quantum Cosmology · Physics 2016-02-04 R. Kabir , A. Mukherjee

Recently we identified a new class of (super)conformally invariant theories which allow inflation even if the scalar potential is very steep in terms of the original conformal variables. Observational predictions of a broad class of such…

High Energy Physics - Theory · Physics 2015-06-16 Renata Kallosh , Andrei Linde

A procedure is developed for the recovery of the inflationary potential over the interval that affects astrophysical scales ($\approx 1\Mpc - 10^4\Mpc$). The amplitudes of the scalar and tensor metric perturbations and their power-spectrum…

Astrophysics · Physics 2013-11-13 M. S. Turner

This paper is aimed to study the compelling issue of cosmic inflation during rapid oscillations using the framework of non-minimal derivative coupling. To this end, an anisotropic and homogeneous Bianchi I background is considered. In this…

General Relativity and Quantum Cosmology · Physics 2018-11-29 Rabia Saleem

We study anisotropic inflationary solutions when the inflaton and its derivative couple to a vector field. This type of coupling is motivated by D-brane inflationary models, in which the inflaton, and a vector field living on the D-brane,…

High Energy Physics - Theory · Physics 2018-06-06 Jonathan Holland , Sugumi Kanno , Ivonne Zavala

We study an inflationary scenario in supergravity model with a gauge kinetic function. We find exact anisotropic power-law inflationary solutions when both the potential function for an inflaton and the gauge kinetic function are…

High Energy Physics - Theory · Physics 2011-03-10 Sugumi Kanno , Jiro Soda , Masa-aki Watanabe

We investigate the dynamics of the recently proposed model of assisted inflation. In this model an arbitrary number of scalar fields with exponential potentials evolve towards an inflationary scaling solution, even if each of the individual…

Astrophysics · Physics 2016-08-25 Karim A. Malik , David Wands

In this paper, we study a constant-roll inflationary model in the presence of a noncommutative parameter with a homogeneous scalar field minimally coupled to gravity. The specific noncommutative inflation conditions proposed new…

High Energy Physics - Theory · Physics 2023-02-14 J. Sadeghi , S. Noori Gashti

We study anisotropic inflation with Gauss-Bonnet correction in presence of a massless vector field. In this scenario, exact anisotropic power-law inflation is realized when the inflaton potential, gauge coupling function and the…

High Energy Physics - Theory · Physics 2016-10-06 Sayantani Lahiri

Anisotropic inflationary background geometries are analyzed in the context of an extended gauge action where the electric and magnetic susceptibilities are not bound to coincide and depend on the inflaton field. After deriving various…

High Energy Physics - Theory · Physics 2014-03-13 Massimo Giovannini

We extend the standard theory of cosmological perturbations to homogeneous but anisotropic universes. We present an exhaustive computation for the case of a Bianchi I model, with a residual isotropy between two spatial dimensions, which is…

Astrophysics · Physics 2008-11-26 A. E. Gumrukcuoglu , Carlo R. Contaldi , Marco Peloso

This paper is devoted to study the warm inflation using vector fields in the background of locally rotationally symmetric Bianchi type I universe model. We formulate the field equations, slow-roll and perturbation parameters (scalar and…

General Relativity and Quantum Cosmology · Physics 2015-06-18 M. Sharif , Rabia Saleem

We study the possibility that inflation is driven by a scalar field together with a vector field minimally coupled to gravity. By assuming an effective potential that incorporates both fields into the action, we explore two distinct…

General Relativity and Quantum Cosmology · Physics 2024-12-09 Manuel Gonzalez-Espinoza , Ramon Herrera