It is a bit uppity to think that a mere human being, such as I, could have the gall to think about what something so superior to me as the Milky Way galaxy would think about. However, it is possible for me, or you, to think about constructing a robot-based-society here on earth and to consider how its offspring could create an interstellar/planetary civilization of intelligent beings. This process of making a civilization the size of the Milky Way would take over a hundred thousand years even if it were done at the speed of light through contacting already existing and cooperative robot societies. “The Milky Way is a barred spiral galaxy with a diameter between 150,000 and 200,000 light-years (ly).”
If it were necessary to physically populate distant stars’ planets using specially designed small probes to travel there, it would take much longer than radio communications. A million years is optimistic for the transit time, although assembling a robot civilization might go much quicker. That is assuming everything went as well as an intelligent being could possibly analyze, project, and build self-replicating devices and goal-directed ones.
Once the first basic device was operational, the following ones would be self-constructed exponentially. This wouldn’t be a Darwin-like evolution of reproduction by those who survived, it would be a directed evolution designed to fit needed applications and environments. A thousand years might be plenty of time to build the equipment necessary for this planet-wide robot-computer society to become a member of the Milky Way civilization.
If this society could be made, even in a portion of the Milky Way, in a billion years, it would be able to think and to make things beyond what we here on earth can now consider feasible. It would be able to construct things that would be beyond the total energy stored in the earth because it could collect energy from its star for billions of years. It could construct very large things in space from materials available in space like the asteroid belts because it would have vast amounts of time, energy, intelligence, wisdom, and vision. What would this being think about, choose to value, and do? My speculation is that it would be something as spectacular as our Earth.
Humans don’t have the lifespan to contemplate things like the robots we can construct can think about and do.