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Title: Bayesian analysis of inflation: Parameter estimation for single field models

Abstract

Future astrophysical data sets promise to strengthen constraints on models of inflation, and extracting these constraints requires methods and tools commensurate with the quality of the data. In this paper we describe ModeCode, a new, publicly available code that computes the primordial scalar and tensor power spectra for single-field inflationary models. ModeCode solves the inflationary mode equations numerically, avoiding the slow roll approximation. It is interfaced with CAMB and CosmoMC to compute cosmic microwave background angular power spectra and perform likelihood analysis and parameter estimation. ModeCode is easily extendable to additional models of inflation, and future updates will include Bayesian model comparison. Errors from ModeCode contribute negligibly to the error budget for analyses of data from Planck or other next generation experiments. We constrain representative single-field models ({phi}{sup n} with n=2/3, 1, 2, and 4, natural inflation, and 'hilltop' inflation) using current data, and provide forecasts for Planck. From current data, we obtain weak but nontrivial limits on the post-inflationary physics, which is a significant source of uncertainty in the predictions of inflationary models, while we find that Planck will dramatically improve these constraints. In particular, Planck will link the inflationary dynamics with the post-inflationary growth of the horizon, andmore » thus begin to probe the ''primordial dark ages'' between TeV and grand unified theory scale energies.« less

Authors:
 [1];  [2];  [3]
  1. Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, Ohio 43210 (United States)
  2. Institute of Astronomy and Kavli Institute for Cosmology, University of Cambridge, Cambridge CB3 0HA (United Kingdom)
  3. Department of Physics, Yale University, New Haven, Connecticut 06520 (United States)
Publication Date:
OSTI Identifier:
21504957
Resource Type:
Journal Article
Journal Name:
Physical Review. D, Particles Fields
Additional Journal Information:
Journal Volume: 83; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevD.83.043505; (c) 2011 American Institute of Physics; Journal ID: ISSN 0556-2821
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; APPROXIMATIONS; ASTROPHYSICS; COMPARATIVE EVALUATIONS; FORECASTING; GRAND UNIFIED THEORY; INFLATIONARY UNIVERSE; RELICT RADIATION; SIMULATION; SPECTRA; TEV RANGE; CALCULATION METHODS; COSMOLOGICAL MODELS; ELECTROMAGNETIC RADIATION; ENERGY RANGE; EVALUATION; FIELD THEORIES; MATHEMATICAL MODELS; MICROWAVE RADIATION; PARTICLE MODELS; PHYSICS; QUANTUM FIELD THEORY; RADIATIONS; UNIFIED GAUGE MODELS

Citation Formats

Mortonson, Michael J, Peiris, Hiranya V, Department of Physics and Astronomy, University College London, London WC1E 6BT, and Easther, Richard. Bayesian analysis of inflation: Parameter estimation for single field models. United States: N. p., 2011. Web. doi:10.1103/PHYSREVD.83.043505.
Mortonson, Michael J, Peiris, Hiranya V, Department of Physics and Astronomy, University College London, London WC1E 6BT, & Easther, Richard. Bayesian analysis of inflation: Parameter estimation for single field models. United States. https://doi.org/10.1103/PHYSREVD.83.043505
Mortonson, Michael J, Peiris, Hiranya V, Department of Physics and Astronomy, University College London, London WC1E 6BT, and Easther, Richard. 2011. "Bayesian analysis of inflation: Parameter estimation for single field models". United States. https://doi.org/10.1103/PHYSREVD.83.043505.
@article{osti_21504957,
title = {Bayesian analysis of inflation: Parameter estimation for single field models},
author = {Mortonson, Michael J and Peiris, Hiranya V and Department of Physics and Astronomy, University College London, London WC1E 6BT and Easther, Richard},
abstractNote = {Future astrophysical data sets promise to strengthen constraints on models of inflation, and extracting these constraints requires methods and tools commensurate with the quality of the data. In this paper we describe ModeCode, a new, publicly available code that computes the primordial scalar and tensor power spectra for single-field inflationary models. ModeCode solves the inflationary mode equations numerically, avoiding the slow roll approximation. It is interfaced with CAMB and CosmoMC to compute cosmic microwave background angular power spectra and perform likelihood analysis and parameter estimation. ModeCode is easily extendable to additional models of inflation, and future updates will include Bayesian model comparison. Errors from ModeCode contribute negligibly to the error budget for analyses of data from Planck or other next generation experiments. We constrain representative single-field models ({phi}{sup n} with n=2/3, 1, 2, and 4, natural inflation, and 'hilltop' inflation) using current data, and provide forecasts for Planck. From current data, we obtain weak but nontrivial limits on the post-inflationary physics, which is a significant source of uncertainty in the predictions of inflationary models, while we find that Planck will dramatically improve these constraints. In particular, Planck will link the inflationary dynamics with the post-inflationary growth of the horizon, and thus begin to probe the ''primordial dark ages'' between TeV and grand unified theory scale energies.},
doi = {10.1103/PHYSREVD.83.043505},
url = {https://www.osti.gov/biblio/21504957}, journal = {Physical Review. D, Particles Fields},
issn = {0556-2821},
number = 4,
volume = 83,
place = {United States},
year = {Tue Feb 15 00:00:00 EST 2011},
month = {Tue Feb 15 00:00:00 EST 2011}
}