The Hubble tension and fifth forces: a cosmic screenplay

Understand

Fifth forces are ubiquitous in modified theories of gravity.

• In this paper, we analyze their effect on the Cepheid-calibrated cosmic distance ladder, specifically with respect to the inferred value of the Hubble constant ($H_0$).
• We consider a variety of effective models where the strength, or amount of screening, of the fifth force is estimated using proxy fields related to the large-scale structure of the Universe.
• For all models considered, the local distance ladder and the Planck value for $H_0$ agrees with a probability $\gtrsim 20 \, \%$, relieving the tension compared to the concordance model with data being excluded at $99 \, \%$ confidence.