Im thinking about writing a science fiction novel with as little ‚fiction‘ as possible and playing in a really, really far future, maybe millions of years, partly because I did not find any story covering this (although duck AI said there are some stories about that, feel free to recommend!). I found one podcast about this thought experiment I have yet to listen to, but nothing else.
So for as little fiction as possible, I need to have a somewhat realistic way of travelling of course. But not only that, communication would take way too long if colonies in different solar systems are lightyears apart.

So I got inspired by the greatest of geniuses Mister Patrick Star („why don’t we just take bikini bottom, and move it somewhere else?“) Now my actual question: would it theoretically be possible to travel with the entire solarsystem? Somehow use the suns energy and bundle it in one direction (but still don’t have the colonised planets get no sunlight) so that we ‚fly‘ to the next solar system, and the distances between us and exoplanets become so small that travelling and communicating between them takes a reasonable time? How would that affect gravity? Would it be possible to calculate and prevent from destroying the gravitational balance of our system or the milkyway?

And further, also move on with the second solar system and start ‚collecting‘ systems? For me, that sounds like the only realistic way to 1. colonise other planets (and not evolve into too different species) and 2. maybe even encounter alien life, maybe if the milkyway and andromeda collide we also will find intelligence.