DESI Dark Energy Time Evolution is Recovered by Cosmologically Coupled Black Holes

Understand

Recent baryon acoustic oscillation (BAO) measurements by the Dark Energy Spectroscopic Instrument (DESI) provide evidence that dark energy (DE) evolves with time, as parameterized by a $w_0 w_a$ equation of state.

• Cosmologically coupled black holes (BHs) provide a DE source that naturally evolves with time, because BH production tracks cosmic star-formation.
• Using DESI BAO measurements and priors informed by Big Bang Nucleosynthesis, we measure the fraction of baryonic density converted into BHs, assuming that all DE is sourced by BH production.
• We find that the best-fit DE density tracks each DESI best-fit $w_0w_a$ model within $1\sigma$, except at redshifts $z \lesssim 0.2$, highlighting limitations of the $w_0w_a$ parameterization.