Joint cosmology seminar at MIT:

Tuesday, October 21, 2025, 2:30 pm
Cosman Seminar Room\\
Center for Theoretical Physics\\
Building 6C, Room 6C-442\\
Massachusetts Institute of Technology

New Physics from the ``Hubble Tension''

Vivian Poulin
Université Montpellier

Abstract:

Over the last decade, measurements of the expansion rate of the universe today, $H_0$, made with cepheid-calibrated SN1a have become increasingly discrepant with the value predicted from the LCDM model when fit to CMB data. After a brief review of the experimental situation, I will show the potential implications of this ``Hubble tension'' for new physics. I will argue that it points to some new mechanism at play in the pre-recombination universe (i.e., redshift $z > 1000$), rather than a new dynamical effect at late-time (i.e. $0 < z < 1$). I will discuss some model-independent implications of the Hubble tension that can help shed light on its origin.