The Multiverse is a concept that refers to the existence of infinite universes that comprise everything that is. Each universe within the multiverse is referred to as a different "Earth", and each vibrates at a different frequency so that they cannot normally interact with or be seen by each other. If one is able to travel fast enough it is possible to breach the laws of physics and travel between these Earths. It is known that there are 52 known Earths within the Multiverse; however, it has been recently discovered that there is another Earth, Earth-53, also known as Earth-X
Known Earths:
Earth-X