I’m working on a hobby writing project and have com me across a bit of an interesting concept. I’m trying to write an intergalactic civilization story but the size of the civilization I’m making (in order to try and justify some of their achievements) is about as big as the Laniakea Supercluster, or around 100,000 galaxies (though this figure is split between a number of super-states).
So far I have come up with a few items to explain the logistics of this. First of all, giant chains of worm-hole based telecommunications outposts are used to allow electromagnetic communication to travel over great distances and thus still allow for instantaneous communication (though these systems require crap tons of energy, thus requiring great numbers of Dyson swarms around stars and black holes to power; this kinda is meant to respect the physics notion of trading distance for energy needed in terms of work [breaker bar to get better leverage], so going over less distance requires more energy). In my story a Next Generation system is being developed that would effectively use the property of particles being quantumly entangled to essentially communicate over great distances and thus transfer information via “Morse code.” Ships are powered by something called “Exotic Matter” (which is just a made up form of matter to justify their ability to use Alcubierre Drives for short-distance travel) that, in limited circumstances, could create their own Einstein-Rosenberg bridges, but usually use jump gates to travel between destinations regularly. Artificial Intelligence is used to manage logistics, communications, and the vast numbers of the logistics employed. Super-states act more as confederacies to garner cooperation among galaxies, and rely on multi-head executive branches to allow for proper representation and for efficient management of a state. The implied massive scale of war means that conflict among super-states is avoided at all costs; militaries aren’t usually small and most investment goes into a smaller number of super-soldiers capable of marine-style operations (especially against pirates) rather than a full-scale operational army.
Other than this, I was kinda trying to think of what kinds of emergent systems would develop here. Kinda like how COVID and people being at home caused the emergence of streaming to let people watch stuff at home, what sort of things should pop up in terms of technology, culture, or politics?
I already kinda see citizens as owing more loyalty to the planet or even galaxy they were raised on. Certain services like hospitals or colleges are spread across local solar neighborhoods; personal ships like in Star Wars aren’t really a thing, as commercial starliners are used instead. The government hosts special intern research areas to allow the longer-living species here to change jobs and not work in the same industry for an entire century (this concept is actually the basis for the story I’m working on). Super-states are multi-species (by the way, this story takes place in a parallel universe to our universe, as I had thought that if trying to create a story around the concept of exoplanets that was mostly theory and with unknown numbers of planets around stars making hard-science hard to do, I may as well create my own systems and use actual science to build it). Science and the continued effort to better their understanding of the universe is essentially their form of patriotism. The concept of space is only lightly backed into common every day life (such as how, say, in Harry Potter songs seem overly “hey we live in a magic world” instead of being from a civilization that has over things going on but does so with magic), such as daycares based based on a variety of planetary ecosystems (like red-hued flora) like how many nurseries use green fields of Earth.
If I could hear any additional thoughts to this, or if you have any questions, I would appreciate to hear them 
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