1. The Multiverse Theory
- Company: Numerous
- Real Science: Physics
- Possible to Recreate: Theoretically
The most popular Multi-Verse concepts are laid out by DC Comics, although most comic brands have one. The way they all lay it out is that there are numerous universes with similar or exact copies of our Earth, people, etc. While the people we are might be different from place to place, the fact at the end of the day is that another one of us is or was present in all of them. You can access the multi-verse through portals or through things like the Speed Force, which The Flash uses a lot.
Due to similar people being present, copies of heroes or villains may be there. The facts about comic book characters on these Earths often differ but there are similarities too. For example, Kryptonite hurts Superman & Supergirl, but Kryptonite from another universe won’t affect them. This also works with the fact that villains may be heroes and heroes may be villains between differing universes. Based on our known and theoretical science, the multi-verse theories presented are possible.