This is all confusing to me. I simply look at the conservation of energy law, which tells us all the energy in existence had no beginning and will have no end. In other words, it is eternal, constant, finite, of fixed value - however you want to word it. Then I dissect reality, or everything in existence from there and ask questions: Is the universe and all its known and undiscovered dimensions everything in existence or is it just a fraction of a more complex reality that could consist of other universes like or very much unlike ours with different laws of physics? Since space-time is an energetic fabric, I imagine there is a point at which it can no longer stretch. At that point, it could simply reverse course if it acted like an elastic or it could quantum leap into something else with different dimensions and laws of physics. Since the expansion appears to still be accelerating, I favor the quantum leap view. The universe could be in a more complex cycle instead of a simple expansion and contraction. That would apply if the universe is all there is, but if it is only a fraction of a more complex, perhaps open reality in which all the energy can interact with only temporary barriers, the picture would be considerably more complex.