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Related papers: Computing the Primordial Power Spectra Directly

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We study the power spectrum of the mass density perturbations in an inflation scenario that includes thermal dissipation. We show that the condition on which the thermal fluctuations dominate the primordial density perturbations can easily…

Astrophysics · Physics 2009-10-31 Wolung Lee , Li-Zhi Fang

Temperature and polarization power spectra of the cosmic microwave background can provide essentially incontrovertible evidence for coherent acoustic oscillations in the early universe. A simple model calculation demonstrates explicitly how…

Astrophysics · Physics 2007-05-23 Arthur Kosowsky

Thermal inflation is a second epoch of exponential expansion at typical energy scales $V^{1/4} \sim 10^{6 \sim 8} \mathrm{GeV}$. If the usual primordial inflation is followed by thermal inflation, the primordial power spectrum is only…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-09 Kihyun Cho , Sungwook E. Hong , Ewan D. Stewart , Heeseung Zoe

We study the asymmetric primordial fluctuations in a model of inflation in which translational invariance is broken by a domain wall. We calculate the corrections to the power spectrum of curvature perturbations; they are anisotropic and…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-02 Sadra Jazayeri , Yashar Akrami , Hassan Firouzjahi , Adam R. Solomon , Yi Wang

We study the power spectra and entropy of two-field warm inflationary scenario with canonical condition which is described by many-dimensional stochastic differential equations. The field perturbations are analytically calculated via a…

General Relativity and Quantum Cosmology · Physics 2019-03-12 Xi-Bin Li , Xiao-Gang Zheng , Jian-Yang Zhu

Single field inflationary models that seek to greatly enhance small scale power in order to form primordial black holes predict both a squeezed bispectrum that is enhanced by this small scale power and a potentially detectable enhancement…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-08 David Zegeye , Keisuke Inomata , Wayne Hu

We present Feynman type diagrams for calculating the n-point function of the primordial curvature perturbation in terms of scalar field perturbations during inflation. The diagrams can be used to evaluate the corresponding terms in the…

High Energy Physics - Theory · Physics 2009-10-09 Christian T. Byrnes , Kazuya Koyama , Misao Sasaki , David Wands

We present a new mechanism for generating primordial statistical anisotropy of curvature perturbations. We introduce a vector field which has a non-minimal kinetic term and couples with a waterfall field in hybrid inflation model. In such a…

Astrophysics · Physics 2011-07-13 Shuichiro Yokoyama , Jiro Soda

We propose a mechanism for generating an inflationary phase in the early universe without resorting to any type of scalar field(s). Instead, this accelerated expansion is driven by a dynamical "cosmological constant" in the framework of…

General Relativity and Quantum Cosmology · Physics 2022-03-18 Gabriel Leon

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

We study the generation of a localized peak in the primordial spectrum of curvature perturbations from a transient dissipative phase during inflation, leading to a large population of primordial black holes. The enhancement of the power…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-16 Guillermo Ballesteros , Marcos A. G. García , Alejandro Pérez Rodríguez , Mathias Pierre , Julián Rey

We compute the universal generic corrections to the inflationary power spectrum due to unknown high-energy physics. We arrive at this result via a careful integrating out of massive fields in the "in-in" formalism yielding a consistent and…

High Energy Physics - Theory · Physics 2013-05-30 Mark G. Jackson , Koenraad Schalm

This article examines how a breakdown of a locally Lorentz invariant, point-like description of nature at tiny space-time intervals would translate into a distinctive set of signals in the primordial power spectrum generated by inflation.…

High Energy Physics - Phenomenology · Physics 2008-11-26 Hael Collins , R. Holman

We numerically compute features in the power-spectrum that originate from the decay of fields during inflation. Using a simple, phenomenological, multi-field setup, we increase the number of fields from a few to thousands. Whenever a field…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Diana Battefeld , Thorsten Battefeld , John T. Giblin , Evan K. Pease

In the primordial universe, fields with mass much larger than the mass-scale of the event-horizon (such as the Hubble parameter in inflation) exist ubiquitously, and can be excited from time to time and oscillate quickly around their…

High Energy Physics - Theory · Physics 2011-06-28 Xingang Chen

Different inflationary models predict oscillatory features in the primordial power spectrum. These can leave an imprint on both the cosmic microwave background (CMB) and the large-scale structure (LSS) of our Universe, that can be searched…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-15 Chenxiao Zeng , Ely D. Kovetz , Xuelei Chen , Yan Gong , Julian B. Muñoz , Marc Kamionkowski

We present a complete framework for numerical calculation of the power spectrum and bispectrum in canonical inflation with an arbitrary number of light or heavy fields. Our method includes all relevant effects at tree-level in the loop…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-23 Mafalda Dias , Jonathan Frazer , David J. Mulryne , David Seery

We set up a formalism that can be used to calculate the power spectrum of the curvature perturbations produced during inflation up to arbitrary order in the slow-roll expansion, and explicitly calculate the power spectrum and spectral index…

Astrophysics · Physics 2009-11-06 Ewan D. Stewart , Jin-Ook Gong

Assuming that inflation is followed by a phase where the energy density of the Universe is dominated by a component with a general equation of state, we evaluate the spectrum of primordial gravitational waves induced in the…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-16 Nicolás Bernal , Fazlollah Hajkarim

A common explanation for the CMB power asymmetry is to introduce a dipolar modulation at the stage of inflation, where the primordial power spectrum is spatially varying. If the universe in the stage of inflation is Finslerian, and if the…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-28 Xin Li , Hai-Nan Lin
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