But it doesn’t matter: In a multiverse, our universe is just one of many. And though it could blow apart and shoot rainbows into the void between universes for all we care, the larger “universe” will still be there. A universe is anything and everything in existence.
And because there’s still matter out there, we’d still have a universe and existence.Even though time itself could run out in other universes, in a multiverse, new universes are being born all the time. According to the physics, the number of new universes will always outnumber the old ones, so in theory, the number of universes is increasing.