General Relativity allows a potentially infinite number of spacetimes that are inaccessible to each other (except perhaps at the event--presumably lacking either duration or extent because of its instantaneity-- of their formation), as far as I can recollect from my sketchy reading of Sklar's analysis of GR (-his book called "Space, Time, and Spacetime"). False-vacuum inflation seems to have taken it over the version known as chaotic inflation, per the Planck Satellite group's intro to their data release earlier this year. However, Guth and Vilenkin both describe a problem getting the false-vacuum bubble (the volume acting like a vacuum which isn't quite the lowest-density vacuum possible) into our spacetime from wherever/whenever it originates, due to its tendency to collapse into a black hole under its own externally-attractive gravity. (Its interior is filled with the repulsive gravity that accounts for inflation, i. e., exponentially accelerated expansion.) Both overcome this by quantum "tunneling", which I understand to be a change not requiring either physical or temporal motion. Vilenkin calls his version "quantum tunneling from nothing", which he claims is allowed by well-established principles of QM. I know that inflation tends to lead into a multiverse where innumerable replicas of myself occupy innumerable replicas of my observable region, but the person I call "Continuous/Contiguous Me" is distinct from its replicas, and doesn't consider that anything that happened longer ago than it took electromagnetism to cross C/CM's synapses exists. So I'm wondering whether the "nothing" Vilenkin visualizes could be physically interpreted as "the past", or (equally well) as "the future". Sorry for all the detail, but I'm hoping it will help people with a clearer knowledge of physics tell me just why it might or might not be.