I cant remember the name of this specific theory
I heard this theory once that, supposing the universe came about out of nothingness, if it were to end, the same state of nothingness would come about again. And because it would be the same exact state as when the universe was formed, due to all the factors being the same, the universe would form once more exactly as it did before. If it forms the same way, it would develop the same way, resulting in everything that happened before happening once again. So the universe just loops.
So i'm wondering what the name of this theory is