As far as I understand, the galaxy of the Star Wars supposedly exists in our universe ("a galaxy far, far away"). So I have to wonder: is the Force (as a metaphysical and ubiquitous power or fundamental interaction) unique to the Star Wars galaxy, or is it spread all over the universe?
Obi-Wan Kenobi stated that the Force acts only on the galactic level, saying:
"Well, the Force is what gives a Jedi his power. It's an energy field created by all living things. It surrounds us and penetrates us; it binds the galaxy together."
But in other sources I've read it described as "the all-pervading vital energy of the universe."
So is the Force some kind of fundamental interaction like gravity that acts on the universal level (in an alternate universe), or it is some other physical phenomena which occurred only in the Star Wars galaxy? If the former, does that mean that Star Wars happened in a galaxy not from our universe, but some other universe, following a Multiverse theory? And if it's the latter, why didn't it spread to other galaxies?