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A formula for the power spectrum of curvature perturbations having any initial conditions in inflation is obtained. Based on the physical conditions before inflation, the possibility exists that the initial state of scalar perturbations is…

High Energy Physics - Theory · Physics 2017-08-23 Shiro Hirai

In order to calculate the power spectrum generated during a stage of inflation, we have to specify the quantum state of the inflaton perturbations, which is conventionally assumed to be the Bunch-Davies vacuum. We argue that this choice is…

Astrophysics · Physics 2010-10-27 C. Armendariz-Picon

We give a new interpretation of the effect of initial state entanglement on the spectrum of vacuum fluctuations. We consider an initially entangled state between two free massive scalar fields in de Sitter space. We construct the initial…

High Energy Physics - Theory · Physics 2016-12-30 Sugumi Kanno

In this work we study models of anisotropic inflation with the generalized non-vacuum initial states for the inflaton field and the gauge field. The effects of non Bunch-Davies initial condition on the anisotropic power spectrum and…

High Energy Physics - Theory · Physics 2014-07-09 Razieh Emami , Hassan Firouzjahi , Moslem Zarei

We study the analytic structure of in-in correlation functions in a deSitter background. The aim of this study is to probe the initial conditions for inflation through the features of correlation functions of the field fluctuations, and…

High Energy Physics - Theory · Physics 2023-04-12 Diptimoy Ghosh , Amartya Harsh Singh , Farman Ullah

We use the excited coherent states built over the initial non-de Sitter modes, to study the modification of spectra of primordial scalar fluctuation. Non-de Sitter modes are actually the asymptotic solution of the inflaton field…

General Relativity and Quantum Cosmology · Physics 2018-04-06 E. Yusofi , M. Mohsenzadeh , M. R. Tanhayi

How sensitive are the predictions of inflation to pre-inflationary conditions when the number of efolds of inflation is not too large? In an attempt to address this question, we consider a simple model where the inflationary era is preceded…

High Energy Physics - Theory · Physics 2016-01-27 Sina Bahrami , Eanna E. Flanagan

We investigate for possible constraints on inflationary initial state from Large Scale Structure (LSS) observations. Using a model-independent framework, we build the template for the generic initial state and construct the matter power…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-07 Debabrata Chandra , Supratik Pal

We show how the choice of an inflationary state that entangles scalar and tensor fluctuations affects the angular two-point correlation functions of the $T$, $E$, and $B$ modes of the cosmic microwave background. The propagators for a state…

High Energy Physics - Theory · Physics 2016-12-14 Hael Collins , Tereza Vardanyan

We compute the non-Gaussianities that arise in single field, slow roll inflationary models arising from arbitrary homogeneous initial states, as well as subleading contributions to the power spectrum. Non Bunch-Davies vacuum initial states…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-12 Sina Bahrami , Éanna É. Flanagan

Recent Planck results motivated us to use non-Bunch-Davies vacuum. In this paper, we use the excited-de Sitter mode as non-linear initial states during inflation to calculate the corrected spectra of the initial fluctuations of the scalar…

High Energy Physics - Theory · Physics 2014-10-07 E. Yusofi , M. Mohsenzadeh

We study the effects of non-trivial initial quantum states for inflationary fluctuations within the context of the effective field theory for inflation constructed by Cheung et al. which allows us to discriminate between different initial…

High Energy Physics - Theory · Physics 2013-11-20 Nishant Agarwal , R. Holman , Andrew J. Tolley , Jennifer Lin

Sudden phase transitions during inflation can give rise to strongly enhanced primordial density perturbations on scales much smaller than those directly probed by cosmic microwave background anisotropies. In this paper, we study the effect…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-26 Mattia Cielo , Gianpiero Mangano , Ofelia Pisanti , David Wands

In the framework of Inflationary theory, the assumption that the quantum state of the perturbations is a non-vacuum state leads to a difficulty: non-vacuum initial states imply, in general, a large energy density of inflaton field quanta,…

Astrophysics · Physics 2007-05-23 Alejandro Gangui , Jerome Martin , Mairi Sakellariadou

Until recently our knowledge of the primordial curvature perturbation was relatively modest. Ever since COBE delivered its map of data we know the scalar spectrum of primordial perturbations is approximately flat, with the power being only…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-24 Raquel H. Ribeiro

Within the framework of inflationary models that incorporate a spontaneous reduction of the wave function for the emergence of the seeds of cosmic structure, we study the effects on the primordial scalar power spectrum by choosing a novel…

General Relativity and Quantum Cosmology · Physics 2017-10-16 Gabriel R. Bengochea , Gabriel León

During inflation, primordial energy density fluctuations are created from approximate de Sitter vacuum quantum fluctuations redshifted out of the horizon after which they are frozen as perturbations in the background curvature. In this…

High Energy Physics - Phenomenology · Physics 2016-09-06 D. J. H. Chung , A. Notari , A. Riotto

When modelling inflaton fluctuations as a free quantum scalar field, the initial vacuum is conventionally imposed at the infinite past. This is called the Bunch-Davies (BD) vacuum. If however an asymptotically Minkowskian past does not…

High Energy Physics - Theory · Physics 2016-11-14 Benedict J. Broy

The effect of the initial conditions in inflation on scalar and tensor perturbations is investigated. Formulae for the power spectra of gravitational waves and curvature perturbations for any initial conditions in inflation are derived, and…

High Energy Physics - Theory · Physics 2007-05-23 Shiro Hirai

The effect of the initial condition of inflation on the power spectra of scalar and tensor perturbations is estimated assuming a slow-roll inflation model. By defining a more general initial state in inflation particular properties of the…

Astrophysics · Physics 2007-10-15 Shiro Hirai , Tomoyuki Takami
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