Pantheon+ constraints on dark energy and modified gravity: An evidence of dynamical dark energy

Understand

We use the latest Type Ia supernovae sample Pantheon+ to explore new physics on cosmic scales.

• Specifically, in light of this new sample, we constrain the interacting dark energy and Hu-Sawicki $f(R)$ gravity models and employ the model-independent Gaussian processes to investigate whether there is an evidence of dark energy evolution.
• We find that Pantheon+ alone just gives weak constraints.
• However, a data combination of Pantheon+ with cosmic microwave background, baryon acoustic oscillations and cosmic chronometers gives a strong constraint on the modified matter expansion rate $\epsilon=0.048\pm0.026$, which indicates that the momentum may transfer from dark energy to dark matter in the dark sector of the universe at the $1.85\,\sigma$ confidence level.