ABSTRACT
This chapter considers how the timeline predicted by ΛCDM via Equation has difficulties accounting for the apparently early formation of supermassive black holes and galaxies, seemingly requiring exotic modifications to the astrophysics we infer at low redshifts for the creation and evolution of the objects. The determination of the black-hole mass using these data thus yields a value accurate to approximately 0.3 dex. From the mass and bolometric luminosity of a given quasar, one may infer the rate at which it grew in time, based on the following straightforward physical argument. The merger history required to form supermassive black holes in the early Universe therefore does not sit comfortably with our current interpretation of Population III star-formation. The chapter examines the most puzzling coincidence in cosmology, having to do with the current age of the Universe in relation to its gravitational ‘size,’ and surmises that the most likely physical reason for its existence is that the gravitational horizon is null.
