The word "multiverse" can take on several meanings. The observable universe that extends to a distance of about 42 billion light-years, our cosmic visual horizon. But there is no reason to suppose that everything ends there. Beyond there could be many, perhaps infinite, domains similar to ours. Each would have started with a different distribution of matter, but they would all be governed by the same laws of physics. Almost since the origin of humanity, the human being has been wondering if we were alone in the universe. Regardless of what one may think about whether or not there is life on other planets, there is a growing number of scientists who defend the multiverse theory. That said, a paradigm arises, where there are different realities apart from ours, located in completely unknown times and spaces. We could affirm that indeed we are not alone. Not only is our planet one among many, but on cosmological scales our universe would also be insignificant. It would be one more among countless universes, each with its own laws. Similar ideas have been considered in many cultures since ancient times. The novelty lies in the fact that the hypothesis is now conceived as a scientific theory, with all the mathematical rigor and experimental verification that this implies, with which we could admit that with this theory the multiverse is part of the infinite nature of the Cosmos. We are always able to find something beyond that we look at. _David Reina & MJC.