I did a search on the forums and only saw older partial references to this. Things have changed a little and I thought this hypothesis felt satisfying and worth debating further. A summary, from my limited understanding - Universe continues to expand. Black holes become dominant and eventually consume everything. Hawking radiation slowly leaks away from each black hole until they evaporate. That leaves a universe full of mass-less energy particles that experience neither time or distance. What does that mean for space-time? Does that even have meaning in this case? Does location have meaning? Isn't that effectively a singularity - > another big bang? Rinse and repeat. The gist is that the next big bang doesn't wait for all black holes to evaporate but that there is a threshold level of particles that triggers a big bang. That means there will be many black holes still in existence as a new big bang occurs. Part of Roger Penrose's new suggestion is that it should be possible to detect these block holes from the previous aeon in the CMB map. As I understand relativity this seems like a meaningful proposition for a cyclic model.