The discovery of cosmic acceleration has presented a unique challenge for
cosmologists. As observational cosmology forges ahead, theorists have struggled
to make sense of a standard model that requires extreme fine tuning. This
challenge is known as the cosmological constant problem. The theory of
gravitational aether is an alternative to general relativity that does not
suffer from this fine-tuning problem, as it decouples the quantum field theory
vacuum from geometry, while remaining consistent with other tests of gravity.
In this paper, we study static black hole solutions in this theory and show
that it manifests a UV-IR coupling: Aether couples the spacetime metric close
to the black hole horizon, to metric at infinity. We then show that using the
Trans-Planckian ansatz (as a quantum gravity effect) close to the black hole
horizon, leads to an accelerating cosmological solution, far from the horizon.
Interestingly, this acceleration matches current observations for stellar mass
black holes. Based on our current understanding of the black hole accretion
history in the Universe, we then make a prediction for how the effective dark
energy density should evolve with redshift, which can be tested with future
dark energy probes.
