The standard model of cosmology, $\mathrm{\Lambda }$ cold dark matter ($\mathrm{\Lambda }\mathrm{CDM}$), is plagued by various tensions with recent observations. The most pressing one is the Hubble tension, where the observed expansion rate of our Universe is $5\sigma$ larger than that predicted by $\mathrm{\Lambda }\mathrm{CDM}$. Recently, the result from DESI also reveals a new inconsistency between the baryon acoustic oscillation and cosmic microwave background (CMB) observations in $\mathrm{\Lambda }\mathrm{CDM}$. It is found that these major cosmological tensions can be traced back to a common physical origin—the nonminimal coupling between gravity and matter, different from the expectation of general relativity (GR). Bayesian model comparison reveals strong evidence of nonminimally coupled gravity over GR and $\mathrm{\Lambda }\mathrm{CDM}$, with a Bayes factor $\ln B=+12.1$. The nonminimal coupling model predicts that gravity in the early Universe should be $\sim 5\%$ stronger on cosmological scales than it is today, which is consistent with current observation and will be tested by upcoming CMB and big bang nucleosynthesis experiments.

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• Alternative gravity theories
• Baryon acoustic oscillations
• Cosmic microwave background
• Dark energy