About the great black hole that swallows up the smaller ones . so then there will be just one black hole . so what happens then . ? There will be such enormous compression at that point that the invisible void just explodes as it can't take any more and the whole of life starts all over again in simple harmonic fashion
Well we need a mechanism to get everything back into black hole universe state.
Right now that theory looks suspect to get everything back to one place with mutual gravity so if we don't have an external stopping force or reflection of expansion it looks more like our BB universe will just expand forever.
Me thinks since our BB universe exists so does a reason for it and mechanism to return it or at least consume parts of our BB universe into the start of another.
Or we simply run into other BB neighbors that halts our expansion then self mutual gravity takes over and we do return to Black hole universe waiting for a pushy neighbor to start ours.
As for matter it does exist but really should be thought of as simply energy in one format.
The trivial amount of stuff Vs the gigantic amount of nothing that makes up everything makes you wonder if things do continue to get smaller than we detect then our universe is nearly all nothing.
Even now with detection of the smallest things it's almost made of nothing now.