A new study explores the implications of dynamical dark energy, modeled as a scalar field non-minimally coupled to gravity, on cosmological and gravitational wave observations. Researchers compared the predictions of a scalar field model with standard siren data, which use gravitational waves and their electromagnetic counterparts to measure cosmological distances. The model predicts a gravitational-wave friction function, α_M(z), which modifies the ratio between the luminosity distance inferred from gravitational waves (D_L^GW) and that from electromagnetic counterparts (D_L^EM).