I love that story, alas it doesn't give me any additional insight on these questions. Plus, the state of the art has progressed much since then. I'm curious wh

I love that story, alas it doesn't give me any additional insight on these questions. Plus, the state of the art has progressed much since then. I'm curious what the latest science says about when the universe is only empty space in thermal equilibrium, would the space itself have any mass, and would that mass be self-attractive? Would there be an even distribution of particles that don't decay (proton?), or if all particles decay, then an even distribution of energy, which also has mass?