New Physics from the “Hubble Tension”

by Dr Vivian Poulin (LUPM, CNRS & U. de Montpellier, France)

Thursday 21 May 2026, 16:00 → 17:00 Australia/Sydney

Over the last decade, measurements of the expansion rate of the universe today, H0, made with cepheid-calibrated SN1a have become increasingly discrepant with the value predicted from the ΛCDM 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 success and limitations of a representative sample of proposed solutions, and some model-independent implications of the Hubble tension that can help shed light on its origin.