i.e. in more detail
The Unruh temperature at our future de Sitter cosmic event horizon is, therefore,
We are located at r = 0 in this observer-dependent dark energy future universe metric explained by Tamara Davis in her Ph.D. where our r = 0 future light cone intersects it.
The static gravity redshift is given in Einstein's GR by
Therefore, since the temperature is proportional to the mean photon energy/frequency
Therefore, the Planck temperature at our future horizon (pixelated hologram computer - Seth Lloyd) is cooled down in the form of advanced Wheeler-Feynman-Hawking-Unruh blackbody real photon radiation to virtual photon zero point vibrations whose wavelength is the geometric mean of the quantum gravity Planck scale with cosmological Hubble scale. I say virtual because classically the horizon is an infinite redshift surface. However, redshifted frequency is not the classical zero, but is c/(geometric mean).
By the circa 1900 quantum thermodynamics of the blackbody radiation, the energy density scales as the fourth power of the effective temperature, therefore, the dark energy density is (Stefan-Boltzmann)
with the factor ~ 10^120 clearly explained.