There must be other universes containing me,
as there must be intelligent life elsewhere.
Imagining one such universe as I napped
in Earth’s sunlight under the blue dome,
I saw myself waking, rested, happy, smiling.
Straight from the Internet (a kind of multiverse, perhaps) comes this information: The multiverse is a hypothetical group of multiple universes that together comprise everything that exists: the entirety of space, time, matter, energy, information, and the physical laws and constants that describe them. The different universes within the multiverse are called “parallel universes”, “other universes”, “alternate universes”, or “many worlds”.
This all sounds like cutting-edge theorizing, but Ancient Greek Atomism proposed that infinite parallel worlds arose from the collision of atoms. In the third century BCE, the philosopher Chrysippus suggested that the world eternally expired and regenerated, suggesting the existence of multiple universes across time. William James used the term “multiverse” in 1895 but in a different context. In 1952, Erwin Schrödinger (of popular cat fame) gave a lecture in which he warned his audience that what he was about to say might “seem lunatic.” He said that his equations seemed to describe several different histories and these were “not alternatives, but all really happen simultaneously.” This sort of duality is called “superposition.”