The ultimate goal of civilization is to plunge the species into a black hole. The reason we do not see any aliens is because they throw themselves into black holes when they become sophisticated enough.
The black hole is the final gateway into the center of the LORD GOD into which all things go and all things are from. This is objective reality. From the perspective (reference frame) of the person entering into the black hole, there is a stretching of infinite knowledge and crushing of infinity density and they are merged into the infinite sea of knowledge and existence and personality of the ETERNAL LORD GOD.
There are no "space empires" because space empires are fantasies for nitwit low level races who haven't become truly advanced. When the race does become advanced and its understanding of reality and truth becomes sophisticated, it's final goal is to collapse the nearest functional start into a black hole and to jump its whole civilization into it entirely.