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Related papers: Enhanced Non-Gaussianity from Excited Initial Stat…

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Modifications of the initial-state of the inflaton field can induce a departure from Gaussianity and leave a testable imprint on the higher order correlations of the CMB and large scale structures in the Universe. We focus on the bispectrum…

High Energy Physics - Theory · Physics 2010-01-05 Pieter Daniel Meerburg , Jan Pieter van der Schaar , Pier Stefano Corasaniti

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 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

We investigate the phenomenological consequences of a modification of the initial state of a single inflationary field. While single-field inflation with the standard Bunch-Davies initial vacuum state does not generally produce a measurable…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Jonathan Ganc , Eiichiro Komatsu

It has been shown that both scalar and tensor modes with non-Bunch-Davies initial states can enhance the amplitudes of the primordial bispectra compared to those with the Bunch-Davies state, especially for wavenumber modes in a flattened…

General Relativity and Quantum Cosmology · Physics 2023-07-13 Shingo Akama , Hiroaki W. H. Tahara

We approach the problem of finding generalized states for matter fields in a de Sitter universe, moving from a group theoretical point of view. This has profound consequences for cosmological perturbations during inflation, and for other…

General Relativity and Quantum Cosmology · Physics 2020-07-06 Pietro Dona , Antonino Marciano

We investigate if the hemispherical asymmetry in the CMB is produced from "asymmetric" excited initial condition. We show that in the limit where the deviations from the Bunch-Davies vacuum is large and the scale of new physics is maximally…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-07 Amjad Ashoorioon , Tomi Koivisto

We review how initial state effects generically yield an oscillatory component in the primordial power spectrum of inflationary density perturbations. These oscillatory corrections parametrize unknown new physics at a scale $M$ and are…

Astrophysics · Physics 2007-05-23 B. Greene , K. Schalm , G. Shiu , J. P. van der Schaar

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

We explore the possibility of a single field quasi-de Sitter inflationary model with general initial state for primordial fluctuations. In this paper, first we compute the power spectrum and the bispectrum of scalar perturbations with…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-02 Sandipan Kundu

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 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

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

We show that a scalar excited state with large occupation numbers during inflation leads to an enhancement of tensor modes and a characteristic pattern of order-one oscillations in the associated stochastic gravitational wave background…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-07 Jacopo Fumagalli , Gonzalo A. Palma , Sébastien Renaux-Petel , Spyros Sypsas , Lukas T. Witkowski , Cristobal Zenteno

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

Cosmological inflation generates a spectrum of density perturbations that can seed the cosmic structures we observe today. These perturbations are usually computed as the result of the gravitationally-induced spontaneous creation of…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-12 Ivan Agullo , Leonard Parker

It has been found that the primordial non-Gaussianity of the curvature perturbation in the case of non-Bunch-Davies initial states can be enhanced compared with those in the case of the Bunch-Davies one due to the interactions among the…

General Relativity and Quantum Cosmology · Physics 2020-07-15 Shingo Akama , Shin'ichi Hirano , Tsutomu Kobayashi

The standard, scale-invariant, inflationary perturbation spectrum will be modified if the effects of trans-Planckian physics are incorporated into the dynamics of the matter field in a phenomenological manner, say, by the modification of…

General Relativity and Quantum Cosmology · Physics 2009-11-10 L. Sriramkumar , T. Padmanabhan

We study squeezed limit $f_{NL}$ generation by excited initial inflationary states in a model independent way. We restrict "excited" to mean a Bogoliubov transformation of the Bunch Davies state. We simultaneously impose the constraints…

High Energy Physics - Theory · Physics 2014-06-02 Aditya Aravind , Dustin Lorshbough , Sonia Paban

Inflationary perturbations in multi-field theories can exhibit a transient tachyonic instability as a consequence of their non-trivial motion in the internal field space. When an effective single-field description is applicable, the…

High Energy Physics - Theory · Physics 2018-11-07 Sebastian Garcia-Saenz , Sébastien Renaux-Petel
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