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Related papers: Non-Gaussianity from Excited Initial Inflationary …

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The sensitivity of inflationary spectra to initial conditions is addressed in the context of a phenomenological model that breaks Lorentz invariance by dissipative effects above some threshold energy $\Lambda$. These effects are obtained…

High Energy Physics - Phenomenology · Physics 2008-11-26 Julian Adamek , David Campo , Jens C. Niemeyer , Renaud Parentani

We explore possible constraints on the inflationary equation state: p=w\rho. While w must be close to -1 for those modes that contribute to the observed power spectrum, for those modes currently out of experimental reach, the constraints on…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Lotty Ackerman , Willy Fischler , Sandipan Kundu , Navin Sivanandam

Canonical models of single-field, slow-roll inflation do not lead to appreciable non-Gaussianity, unless derivative interactions of the inflaton become uncontrollably large. We propose a novel slow-roll scenario where scalar perturbations…

High Energy Physics - Theory · Physics 2016-05-25 David Pirtskhalava , Luca Santoni , Enrico Trincherini , Filippo Vernizzi

We study the primordial non-Gaussinity predicted from simple models of inflation with a linear potential and superimposed oscillations. This generic form of the potential is predicted by the axion monodromy inflation model, that has…

High Energy Physics - Phenomenology · Physics 2014-11-20 Steen Hannestad , Troels Haugboelle , Philip R. Jarnhus , Martin S. Sloth

Resonant particle production, along with many other physical processes which change the effective equation of state (EOS) during inflation, introduces a step-like feature in the primordial power spectrum. We calculate observational…

Astrophysics · Physics 2009-11-07 Oystein Elgaroy , Steen Hannestad , Troels Haugboelle

We investigate non-Gaussianity in the modulated reheating scenario where fluctuations of the decay rate of the inflaton generate adiabatic perturbations, paying particular attention to the non-linearity parameters $f_{\rm NL}, \tau_{\rm…

Astrophysics · Physics 2008-11-26 Kazuhide Ichikawa , Teruaki Suyama , Tomo Takahashi , Masahide Yamaguchi

I present a brief review of astro-ph/0406099, which argues that there is a limit on the number of efolds of inflation which are observable in a universe which undergoes an eternally accelerated expansion in the future. Such an acceleration…

High Energy Physics - Theory · Physics 2007-05-23 Matthew Kleban

In connection with recent experiments on excitation in which Mott insulators change to conductors, we study the properties of excited states beyond the Mott gap as quasi-stationary states for a two-dimensional Hubbard (t-t'-U) model at half…

Strongly Correlated Electrons · Physics 2022-11-11 Hisatoshi Yokoyama , Kenji Kobayashi , Tsutomu Watanabe , Masao Ogata

Various inflationary scenarios can often be distinguished from one another by looking at the squeezed limit behavior of correlation functions. Therefore, it is useful to have a framework designed to study this limit in a more systematic and…

High Energy Physics - Theory · Physics 2016-08-19 Mehrdad Mirbabayi , Marko Simonović

We develop a cosmological model where primordial inflation is driven by a 'solid', defined as a system of three derivatively coupled scalar fields obeying certain symmetries and spontaneously breaking a certain subgroup of these. The…

High Energy Physics - Theory · Physics 2015-06-11 Solomon Endlich , Alberto Nicolis , Junpu Wang

We examine a type of features in the primordial scalar power spectrum, namely, the bump-like feature(s) that arise as a result of burst(s) of particle production during inflation. The latest CMB observations by Planck 2018 can accommodate…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-07 Suvedha Suresh Naik , Pravabati Chingangbam , Kazuyuki Furuuchi

As the result of synthesis of nuclei with large proton numbers a new region of investigations of the structure of nuclei has been discovered. Due to the recent significant increase in the yield of superheavy nuclei their gamma-spectroscopic…

Nuclear Theory · Physics 2022-03-25 N. Yu. Shirikova , A. V. Sushkov , L. A. Malov , E. A. Kolganova , R. V. Jolos

Recently a mechanism was proposed whereby the primordial density perturbations are generated at the end of inflation. We continue the analysis of the proposed model of this mechanism and calculate the maximum extent to which the density…

Astrophysics · Physics 2009-11-13 Michael P. Salem

The physics during the inflationary stage of the universe is of quantum nature involving extremely high energy densities. Moreover, it is out of equilibrium on a fastly expanding dynamical geometry. We complement here the 1999 Chalonge…

Astrophysics · Physics 2007-05-23 H. J. de Vega

We consider a noncommutative (NC) inflationary model with a homogeneous scalar field minimally coupled to gravity. The particular NC inflationary setting produces entirely new consequences. We first analyze the free field case and…

General Relativity and Quantum Cosmology · Physics 2018-05-01 S. M. M. Rasouli , N. Saba , M. Farhoudi , J. Marto , P. Moniz

We study an inflationary scenario with a two-form field to which an inflaton couples non-trivially. First, we show that anisotropic inflation can be realized as an attractor solution and that the two-form hair remains during inflation. A…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-16 Junko Ohashi , Jiro Soda , Shinji Tsujikawa

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 investigate the formation of non-ground-state Bose-Einstein condensates within the mean-field description represented by the Gross-Pitaevskii equation (GPE). The objective is to form excited states of a condensate known as nonlinear…

Atomic Physics · Physics 2026-01-14 Leonardo Brito da Silva , Emanuel Fernandes de Lima

We explore inflation via the effective potential of the minimal Wess-Zumino model, considering both the real and imaginary components of the complex field. Using transport techniques, we calculate the full allowed range of $n_s$, $r$ and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 John Ellis , Nick E. Mavromatos , David J. Mulryne

We study particle production at the preheating era in inflation models with nonminimal coupling $\xi \phi^2R$ and quartic potential $\lambda \phi^4/4$ for several cases: real scalar inflaton, complex scalar inflaton and Abelian Higgs…

High Energy Physics - Phenomenology · Physics 2017-03-08 Yohei Ema , Ryusuke Jinno , Kyohei Mukaida , Kazunori Nakayama