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We study an inflationary scenario with a vector impurity. We show that the universe undergoes anisotropic inflationary expansion due to a preferred direction determined by the vector. Using the slow-roll approximation, we find a formula to…

High Energy Physics - Phenomenology · Physics 2008-11-26 Sugumi Kanno , Masashi Kimura , Jiro Soda , Shuichiro Yokoyama

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

We study the Schwinger effect during inflation and its imprints on the primordial power spectrum and bispectrum. The produced charged particles by Schwinger effect during inflation can leave a unique angular dependence on the primordial…

High Energy Physics - Theory · Physics 2019-04-12 Wan Zhen Chua , Qianhang Ding , Yi Wang , Siyi Zhou

Supersolid inflation is a class of inflationary theories that simultaneously breaks time and space reparameterization invariance during inflation, with distinctive features for the dynamics of cosmological fluctuations. We investigate…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-19 Angelo Ricciardone , Gianmassimo Tasinato

A possible origin of the anomalous dip and bump in the primordial power spectrum, which are reconstructed from WMAP data corresponding to the multipole $\ell=100\sim 140$ by using the inversion method, is investigated as a consequence of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Kohei Kumazaki , Shuichiro Yokoyama , Naoshi Sugiyama

We compute all N-point primordial curvature correlation functions from inflation at tree-level up to N of order ten or more depending on the choice of parameters. This is achieved for resonant inflationary models in which the inflaton…

High Energy Physics - Theory · Physics 2011-05-31 Louis Leblond , Enrico Pajer

We consider the primordial gravity wave background produced by inflation. We compute the small anisotropy produced by the primordial scalar fluctuations.

High Energy Physics - Theory · Physics 2016-04-20 Vasyl Alba , Juan Maldacena

In this paper we investigate the cosmological dynamics of geometric inflation by means of the tools of the dynamical systems theory. We focus in the study of two explicit models where it is possible to sum the infinite series of higher…

General Relativity and Quantum Cosmology · Physics 2021-03-31 Israel Quiros , Roberto De Arcia , Ricardo García-Salcedo , Tame Gonzalez , Francisco X. Linares Cedeño , Ulises Nucamendi

We calculate power spectra of cosmological perturbations at high accuracy for two classes of inflation models. We classify the models according to the behaviour of the Hubble distance during inflation. Our approximation works if the Hubble…

Astrophysics · Physics 2009-11-06 Dominik J. Schwarz , Cesar A. Terrero-Escalante , Alberto A. Garcia

In this paper, we revisit the estimation of the spectrum of primordial gravitational waves originated from inflation, particularly focusing on the effect of thermodynamics in the Standard Model of particle physics. By collecting recent…

High Energy Physics - Phenomenology · Physics 2018-05-18 Ken'ichi Saikawa , Satoshi Shirai

In this paper we consider how non-Gaussianity of the primordial density perturbation and the amplitude of gravitational waves from inflation can be used to determine parameters of the curvaton scenario for the origin of structure. We show…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-22 José Fonseca , David Wands

The primordial bispectrum has been considered in the past decade as a powerful probe of the physical processes taking place in the early Universe. Within the inflationary paradigm, the properties of the bispectrum are one of the keys that…

General Relativity and Quantum Cosmology · Physics 2015-03-09 Gabriel Leon , Daniel Sudarsky

We propose a novel enhancement mechanism of the curvature perturbations in the nonminimal derivative coupling inflation model with a coupling parameter related to the inflaton field. By considering a special form of the coupling parameter…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-26 Chengjie Fu , Puxun Wu , Hongwei Yu

We compute the full bispectra, namely both auto- and cross- bispectra, of primordial curvature and tensor perturbations in the most general single-field inflation model whose scalar and gravitational equations of motion are of second order.…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-20 Xian Gao , Tsutomu Kobayashi , Maresuke Shiraishi , Masahide Yamaguchi , Jun'ichi Yokoyama , Shuichiro Yokoyama

Future cosmic microwave background polarization experiments will search for evidence of primordial tensor modes at large angular scales, in the multipole range $4 \leq \ell \leq 50.$ Because in that range there is some mild evidence of…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-26 Gonzalo A. Palma , Bastian Pradenas , Walter Riquelme , Spyros Sypsas

We compute the primordial scalar, vector and tensor metric perturbations arising from quantum field inflation. Quantum field inflation takes into account the nonperturbative quantum dynamics of the inflaton consistently coupled to the…

Astrophysics · Physics 2009-11-11 F. J. Cao

Recently there have been differing viewpoints on how to evaluate the curvature power spectrum generated during inflation. Since the primordial curvature power spectrum is the seed for structure formation and provides a link between…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-06 Mar Bastero-Gil , Arjun Berera , Namit Mahajan , Raghavan Rangarajan

The statistical properties of the primordial density perturbations has been considered in the past decade as a powerful probe of the physical processes taking place in the early universe. Within the inflationary paradigm, the properties of…

General Relativity and Quantum Cosmology · Physics 2015-06-15 Gabriel Leon , Daniel Sudarsky

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

The possibility that primordial black holes constitute a fraction of dark matter motivates a detailed study of possible mechanisms for their production. Black holes can form by the collapse of primordial curvature fluctuations, if the…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-06 Ogan Özsoy , Gianmassimo Tasinato
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