I love thinking about these types of theories.
Some scientists believe in this theory:
'Many-worlds interpretation'
The many-worlds interpretation is an interpretation of quantum mechanics that asserts the objective reality of the universal wavefunction and denies the actuality of wavefunction collapse.
Many-worlds implies that all possible alternate histories and futures are real, each representing an actual "world" (or "universe"). In lay terms, the hypothesis states there is a very large—perhaps
infinite—number of universes, and everything that could possibly have happened in our past, but did not, has occurred in the past of some other universe or universes. The theory is also referred to
as MWI, the relative state formulation, the Everett interpretation, the theory of the universal wavefunction, many-universes interpretation, or just many-worlds.
[font=Tahoma, Verdana, Arial, sans-serif]Anything possible that could have happened today is happening somewhere else in the universe.[/font]
[video=youtube]
https://www.youtube.com/watch?v=1KN6a8inOF8[/video]
You should also watch this video!
[video=youtube]
https://www.youtube.com/watch?v=eGguwYPC32I[/video]