Cosmic birefringence from the Axiverse
Gasparotto, Silvia (Universitat Autònoma de Barcelona. Departament de Física)
Sfakianakis, Evangelos I. (Institut de Física d'Altes Energies)

Date:	2023
Abstract:	We revisit the evidence for CMB birefringence in the context of a rich Axiverse. Using probability density functions (PDFs) for various axion parameters, such as the mass and axion decay constant, we construct the PDF for the cosmic birefringence angle and investigate its properties. By relating the observed value of the birefringence angle to the mean or standard deviation of the constructed PDF, we constrain the shape of the input PDFs, providing insights into the statistical distribution of the Axiverse. We focus on three different types of axion potentials: cosine, quadratic, and asymptotically linear axion monodromy. Our analysis showcases the potential of cosmic birefringence in constraining the distribution of axion parameters and uncovering possible correlations among them. We additionally offer predictions for "birefringence tomography", anticipating future measurements of birefringence from lower multipoles, and show how it can be used to rule out simpler versions of the Axiverse. Our findings contribute to the ongoing exploration of the Axiverse and its implications for cosmic birefringence.
Grants:	"la Caixa" Foundation 100010434 European Commission 847648 Agència de Gestió d'Ajuts Universitaris i de Recerca 2022/FI-SDUR Agència de Gestió d'Ajuts Universitaris i de Recerca 2021/SGR-00649
Rights:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, la comunicació pública de l'obra i la creació d'obres derivades, fins i tot amb finalitats comercials, sempre i quan es reconegui l'autoria de l'obra original.
Language:	Anglès
Document:	Article ; recerca ; Versió publicada
Subject:	Axions ; CMBR polarisation ; String theory and cosmology
Published in:	Journal of Cosmology and Astroparticle Physics, Vol. 2023 (November 2023) , art. 17, ISSN 1475-7516

DOI: 10.1088/1475-7516/2023/11/017

39 p, 3.9 MB

The record appears in these collections:
Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > Institut de Física d’Altes Energies (IFAE)
Articles > Research articles
Articles > Published articles