New physics in our universe? The Hubble tension and early dark energy | Colóquio do DFMA

terça-feira, 6 Dezembro, 2022 - 14:00 até 15:00
Profa. Dra. Elisa Gouvea Ferreira - FISMAT IFUSP


Resumo: One of the key topics in cosmology nowadays is the Hubble tension, a discrepancy in the present value of the expansion of our universe (H0) coming from direct (local), and indirect measurements of H0. The most significant tension is between the inferred H0 from the cosmic microwave background (CMB) by Planck, for the ΛCDM model,  and the local one from SHOES, reaching a 5σ discrepancy. This tension could hint at new physics beyond the standard ΛCDM model. A dark energy-like component in the early universe, known as early dark energy (EDE), is a proposed solution to the Hubble tension. Currently, there is no consensus in the literature as to whether EDE can simultaneously solve the Hubble tension and provide an adequate fit to the data from the CMB and large-scale structure of the universe. In this talk, I will first review the status of the Hubble tension, and some of the models that try to address it, focusing on the EDE model and its current constraints. I will show that previous analyses suffered from statistical effects that biased their result toward the conclusion that only a small fraction of EDE was allowed by data. We use a frequentists analysis to show that EDE indeed resolves the Hubble tension and remains one of the main solutions to restore concordance in cosmology. I will also talk about the role of the massive neutrinos in these scenarios and if neutrinos can make EDE a more viable model for our universe.

Desenvolvido por IFUSP