Giarè, W., De Angelis, M., van de Bruck, C. orcid.org/0000-0001-8311-8941 et al. (1 more author) (2023) Tracking the multifield dynamics with cosmological data: a Monte Carlo approach. Journal of Cosmology and Astroparticle Physics, 2023 (12). 014. ISSN 1475-7516
Abstract
We introduce a numerical method specifically designed for investigating generic multifield models of inflation where a number of scalar fields ϕK are minimally coupled to gravity and live in a field space with a non-trivial metric Script G>IJ(ϕK). Our algorithm consists of three main parts. Firstly, we solve the field equations through the entire inflationary period, deriving predictions for observable quantities such as the spectrum of scalar perturbations, primordial gravitational waves, and isocurvature modes. We also incorporate the transfer matrix formalism to track the behavior of adiabatic and isocurvature modes on super-horizon scales and the transfer of entropy to scalar modes after the horizon crossing. Secondly, we interface our algorithm with Boltzmann integrator codes to compute the subsequent full cosmology, including the cosmic microwave background anisotropies and polarization angular power spectra. Finally, we develop a novel sampling algorithm able to efficiently explore a large volume of the parameter space and identify a sub-region where theoretical predictions agree with observations. In this way, sampling over the initial conditions of the fields and the free parameters of the models, we enable Monte Carlo analysis of multifield scenarios. We test all the features of our approach by analyzing a specific model and deriving constraints on its free parameters. Our methodology provides a robust framework for studying multifield inflation, opening new avenues for future research in the field.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2023 The Author(s). Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. https://creativecommons.org/licenses/by/4.0/ |
Keywords: | inflation, Inflation and CMBR theory; Statistical sampling techniques |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Science (Sheffield) > School of Mathematics and Statistics (Sheffield) |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 20 Dec 2023 11:51 |
Last Modified: | 20 Dec 2023 11:51 |
Status: | Published |
Publisher: | IOP Publishing |
Refereed: | Yes |
Identification Number: | 10.1088/1475-7516/2023/12/014 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:206792 |
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Licence: CC-BY 4.0