A Universal Maximum Energy Density

I've explored this line of thought before and so seeing it in a paper caught my eye. The mass per event horizon ratio of black holes also conforms to this limitation, reaching a maximal point at the minimum mass of any observed black hole.

This matters, in part, because quantum gravity theories need infrared or ultraviolet fixed point boundaries to be mathematically consistent, and this might be a way to provide that boundary.

One generic consequence of such a hypothesis is the primordial black holes smaller than stellar black holes don't simply not exist, they theoretically can't exist.

Recent astronomical observations of high redshift quasars, dark matter-dominated galaxies, mergers of neutron stars, glitch phenomena in pulsars, cosmic microwave background and experimental data from hadronic colliders do not rule out, but they even support the hypothesis that the energy-density in our universe most likely is upper-limited by ρ(unimax), which is predicted to lie between 2 to 3 the nuclear density ρ0. 

Quantum fluids in the cores of massive neutron stars with ρ≈ρ(unimax) reach the maximum compressibility state, where they become insensitive to further compression by the embedding spacetime and undergo a phase transition into the purely incompressible gluon-quark superfluid state. 

A direct correspondence between the positive energy stored in the embedding spacetime and the degree of compressibility and superfluidity of the trapped matter is proposed.

In this paper relevant observation signatures that support the maximum density hypothesis are reviewed, a possible origin of ρ(unimax) is proposed and finally the consequences of this scenario on the spacetime's topology of the universe as well as on the mechanisms underlying the growth rate and power of the high redshift QSOs are discussed.

A.A. Hujeirat "Does our universe conform with the existence of a universal maximum energy-density ρ(unimax)?" arXiv (April 13, 2021).