Sol Project. Go check it out if you haven't already noticed it. We'll use this thread for co-ordination. Alternatively, you could use this thread to tell me why the project is a bad idea and call me gay or something. That's your right as a denizen of the internet.
Technically this subforum is for fiction collaboration, but what the hell.
We currently have a basic timeline for Sol up until the Jovian war, the bit we have now is mostly the domain of those of us willing to brave hard sf, as pre-enlightenment events play a major role. I've added a projects section to the top navbar and linked the sol project in the current projects list.
I say we should just figure out some cool things for the system as it is today, then work our way back to the Jovian war to justify it. Normally I don't support doing it backwards like that, but with a period of 2000 years we've got plenty of room to play with.
Adding historical events and major disaster is completely allowed, by the way. 2000 years is a long time, and shit will happen.
I suggest a Dyson sphere. Not a shell, but a good-old-fashioned sphere of stations and solar collectors swarming around the sun. Maybe it's only partly completed, I dunno. I made a cool design for a Dyson sphere "template" habitat, if anyone likes the idea.
The primary reason why I'm hesitant on including a Dyson structure (such as a swarm) is that it would by default open up the prospect of von neumann machines. Which in themselves might not be so bad, but it does create a kind of super ambiguous upper limit on the scale of structures we can establish.
Edit:
But if it's only partly completed… then I wouldn't be as opposed to the suggestion.
Theres nothing that inherently prevents von-neumann machines from working in the setting, though. They just give you materials, they don't really help with the insane amount of engineering and structural work that would be required to make things like star-encircling ringworlds or dyson shells.
My main objection to dyson spheres is the lack of population density to justify them. The entire Solar Union in 4500 has a population of around 490 billion. With a bit of squeezing you could fit all of that onto the planets and moons of the sol system without too much difficulty. And the Solar Union has like 900 stars with significant population. There simply isn't a reason to build a full Dyson. Although I suppose a solar collection swarm for some enormous energy-consuming project works.
Oh I consider any Dyson to be solar collectors by default. The whole concept of a solid-shell dyson is just insane. Can you imagine the complexity involved in maintaining the habitability along the inner surface? Even assuming some magic artificial gravity, it would be incomprehensibly complicated.
A swarm of solar collectors is best, that or the gossamer bubble approach… Where 2 semi-spheres of super thin solar cells are placed on top and bellow the star. Usually with a ring-world in the middle, but that doesn't need to be specified.
Antimatter production is one thing that could require these levels of solar collectors. Most methods that we know of for producing antimatter function at less than 1 percent efficiency. Assuming you have a fleet of a thousand ships that requires several tons of the stuff a day… regular nuclear fusion might just not cut it.
Amat production might justify it, I admit. As long as the swarm isn't dense enough to significantly affect the apparent luminosity of the star.
Antimatter factories have been mentioned in the Mercury page, feel free to write a page for them.
Incidentally, I'd like to talk about the history a bit, does anybody have ideas for major events beyond what's outlined on the history of sol page so far?