Matter is matter. There are only so many ways it can exist and interact with other matter, forces, energy, etc. We have seen most of them, and can perform experiments to see the rest.
You are not going to go to another galaxy and find that suddenly the laws of physics stop applying or get changed (except if you go to a black hole, which I don't know what that is like
). Not the wording of the laws, but the actual way in which the universe exists and functions. That is what our physical laws are based off of. The basic properties of the universe are not going to change from one galaxy to the next.