Hubble Tension as a Window on the Gravitation of the Dark Matter Sector

A simple and minimal extension of the standard cosmological ΛCDM model in which dark matter experiences an additional long-range scalar interaction is demonstrated to alleviate the long-lasting Hubble tension while primordial nucleosynthesis predictions remain unaffected and passing by construction all current local tests of general relativity. The theoretical formulation of this ΛβCDM model and its comparison to astrophysical observations are presented to prove its ability to fit existing data and potentially resolve the tension.