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[OngBonga]

Another way of thinking about the hollow black hole is to think of a bubble with enormous surface tension. Where does the surface tension come from? Gravity. Each particle is so close to the next particle that they are basically gravitationally bound to one another. The stream of particles moving at near light speed around the event horizon could be thought of as an unbreakable sheet of paper, that as far as the particle is concerned the universe is two dimensional... forwards in time. There's no falling downwards because of the kinetic energy making you go forwards, and the enormous gravity of the particles occupying almost the same location in spacetime, much closer to one another than in atoms where EM dominates. The only effect the downwards gravity of the entire system has it to create the curvature rrequired to maintain the sphere.

Another problem with singularities is that as they approach one another, their velocities will exceed light speed. We have a problem here if the singularities are where the mass is.

[MadMojoMonkey]

Another way of thinking about the hollow black hole is to think of a bubble with enormous surface tension. Where does the surface tension come from? Gravity. Each particle is so close to the next particle that they are basically gravitationally bound to one another. The stream of particles moving at near light speed around the event horizon could be thought of as an unbreakable sheet of paper, that as far as the particle is concerned the universe is two dimensional... forwards in time. There's no falling downwards because of the kinetic energy making you go forwards, and the enormous gravity of the particles occupying almost the same location in spacetime, much closer to one another than in atoms where EM dominates. The only effect the downwards gravity of the entire system has it to create the curvature rrequired to maintain the sphere.

Another problem with singularities is that as they approach one another, their velocities will exceed light speed. We have a problem here if the singularities are where the mass is.

Sounds a lot like my "not yet known quantum force" hypothesis, IMO.

I mean, it's not gravity. Gravity is so, so much weaker than electromagnetism and piddly compared to the strong force. Ever seen a water droplet hanging from the underside of a surface? It has a whole planet's worth of gravity pulling on it, and only the surface tension interactions of E&M to hold up its entire volume. E&M wins despite the unfathomable ratio of interactions by gravity being overwhelmed by a paltry number of E&M interactions.

The gravity of particles occupying "almost the same space" will be nothing compared to their E&M interactions from being that closely packed.

We'd need to consider the wave functions, though. Superfluid helium cannot boil because the wave functions for the atoms have spread out so much due to cooling that they overlap each other. In effect, the fluid condenses into a single quantum bulk. It's no longer mathematically clear "which" atoms should be boiling, so they perfectly conduct heat through the volume. The He still rapidly evaporates off the top of the surface, but it can no longer form localized hot spots which could turn into bubbles (boil).

This is because even though the He atoms are made of fermions (which have non-integer spin and therefore obey the Pauli Exclusion Principle), the atoms themselves contain an ensemble spin which is an integer. This means that while the constituent parts of each atom still obey the PEP, the atoms themselves do not. This means that the atoms can exist in the same state in the same quantum system at the same time.

So the idea that the particles may overlap is acceptible, so long as the collection of fermions comes together to form a particle that is itself a boson.