Cosmic Recombination with Primordial Magnetic Fields and the Hubble Tension.

          @misc{ pirsa_PIRSA:25030156,
            doi = {10.48660/25030156},
            url = {https://pirsa.org/25030156},
            author = {},
            keywords = {Cosmology},
            language = {en},
            title = {Cosmic Recombination with Primordial Magnetic Fields and the Hubble Tension.},
            publisher = {Perimeter Institute},
            year = {2025},
            month = {mar},
            note = {PIRSA:25030156 see, \url{https://pirsa.org}}
          }
          

Abstract

Primordial Magnetic Fields (PMFs), long studied as potential relics of the early Universe, can accelerate recombination and have been proposed as a possible solution to the Hubble tension. In this seminar, I will present the latest observational evidence supporting this idea, based on comprehensive magnetohydrodynamic (MHD) simulations of recombination in the presence of PMFs. Current Cosmic Microwave Background (CMB) and Baryon Acoustic Oscillation (BAO) data exhibit a mild preference for PMFs while predicting a higher Hubble constant. Notably, the inferred field strengths align with those required to explain galaxy cluster magnetic fields purely from primordial origins, eliminating the need for additional dynamo amplification or stellar contributions. Future high-resolution CMB temperature and polarization measurements will be crucial in confirming or further constraining the role of PMFs during recombination.