2020/04/03 by Miguel Escudero, Escudero, Miguel, Samuel J. Witte +1
Physics and Astronomy · #Cosmology and Gravitation Theories #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #Dark Matter and Cosmic Phenomena #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #Particle physics theoretical and experimental studies
paper · pdf · doi:10.48550/arxiv.2004.01470
openalex publication_date 2020/04/03 · openalex created_date 2023/04/20 · openalex updated_date 2026/07/28
Local measurements of the Hubble constant currently disagree with the\nhigh-precision value that is inferred from the CMB under the assumption of a\n\ΛCDM cosmology. The significance of this tension clearly motivates\nstudying extensions of the standard cosmological model capable of addressing\nthis outstanding issue. Broadly speaking, models that have been successful in\nreducing the the tension between the CMB and local measurements (without\nintroducing additional tension in other datasets) require an additional\ncomponent of the energy density in the Universe at a time close to\nrecombination.\n In this contribution, I will show that the Majoron -- a pseudo-Goldstone\nboson arising from the spontaneous breaking of a global lepton number symmetry\nand often associated with the neutrino mass mechanism -- can help to reduce the\nHubble tension. Importantly, I will also show that current CMB observations can\nconstrain neutrino-Majoron couplings as small as 10-13, which within the\ntype-I seesaw mechanism correspond to scales of lepton number breaking as high\nas \∼ 1 ,\TeV.\n