Why would culture change fast in the distant future? IMO the main reason ours is changing fast now is because the technology is. ISTM that in the distance future technology will become mostly stagnant and so will philosophy. At some point stuff will have been discussed to death, law books will be the mass of a black hole, and history will have a gazillion examples of what works and what doesnt and the SDMB search function still wont work worth crap.
After eons, IMO, culture will become quite stagnant and stable as well, as long as folks are reasonably comfortable. I think its perfectly possible that a distance highly advanced civilization will change as slowly culturally as the middle ages did.
You laugh, but as one of the few social scientists in a field saturated by physical scientists, I can tell you that I know a lot more about their fields than they know about mine.
How long did Pol Pot last? Dictatorships are unstable.
Are you assuming a lack of technology on the colony worlds? As Spock said, military secrets are the most fleeting of all. If in the years the ships are in transit the colony builds a space fleet that can ambush it, it is all over. There are a lot more people on the planet than there are on the ship, and because the ship is moving at .99c they have a lot more time to work. Imagine Hitler sending his very best tanks, planes, and V2s to annihilate the US, 20 years away, though only a few months ship time. As they arrive in the 1965 US, the Army and Air Force has a good laugh as they cream the invaders. I don’t buy no technological progress, especially under this kind of pressure.
An occupying army would be more plausible, but there is the problem of going native and the bigger problem of dealing with an uprising when the first reenforcements won’t arrive for a decade.
At some points in time, not always. Many tyrannies have lasted for centuries. And they didn’t have advantages like mind control and AIs programmed for absolute loyalty.
Eventually we will discover all the laws of physics, and many technologies will be “finished” technologies. Logically, there should be hard upper limits to things like the strength of materials, the power of explosives, the power of engines and so forth. No amount of pressure will let you invent the physically impossible.
Use a robotic army designed for loyalty, one powerful enough that it can’t be overcome by local resources that can be built up secretly.
Don’t forget the energy requirements for travel at those kinds of speeds. Assuming a non-magical spaceship, You’ll never get anywhere near the speed of light, since the energy required for constant acceleration increases as the relativistic mass of the spaceship increases. For various reasons, you’d probably never go above .7c or so - the energy requirements increase exponentially as you approach the speed of light.
Then don’t forget you have to accelerate out halfway, and decelerate for the other half. So if you hit a peak of .7C, your average velocity is .35. So the closest star is suddenly 12 years away.
But even getting to 10% of the speed of light would require so much energy that the cost of the trip would be astronomical, so to speak. So then you have to ask yourself “What are you getting out of this empire?” The energy costs are too great to ever ship raw materials or people back and forth. All defenses would have to be built locally, and you could never send armadas of warships back and forth - you’ll be lucky to send wispy little ships with miniscule payloads compared to the size of the fuel source required. Even antimatter with pure capture of the energy and pure conversion to velocity would require thousands of kilograms of fuel to accelerate a kilogram of payload to .7 C.
I agree with Der Trihs. I don’t think you’re going to see large numbers of humans traveling to other star systems, period. If you want to do a story on a galactic civilization, I’d posit one where self-replicating robot probes have created manufacturing facilities on many worlds, and then human intelligence is beamed to them as pure information and new bodies for the beamed minds are constructed on the spot. That gets you low-cost ‘transport’ of people from one star system to another. It also means you could build up armies very quickly - use pre-canned minds, and now you can build an army as fast as you can make the bodies for them.
I still think it wouldn’t work in terms of directly controlling an empire, because the lag times are too great. But you could great an empire of local autonomous planets run by people uncorked by robots, with their loyalty to the mother planet already ingrained in their minds.
It depends on whether there would be any interdependence between the colonies. Say, for instance, that there is a planet that has very large deposits of rhodium, but has an environment that makes food production impossible or impractical. A small colony is set up. Let’s call it New Rhodesia. New Rhodesia has an arrangement with Earth wherein it sends Earth regular shipments of rhodium in exchange for regular shipments of food (or phosphorus or whatever important element happens to be scarce on New Rhodesia). The shipments could be sent on unmanned vessels travelling at a low fraction of C to keep energy costs down, as long as they are sent regularly. Thus we have have a colony dependent on the homeworld, and a homeworld that benefits from having a colony.
Now add a few dozen more colonies that are similarly dependent on a homeworld, and a few colonies on Earth-like planets that could (relatively) rapidly grow to the point where they can support colonies of their own (or arrange trade agreements with the existing colonies). Even if they aren’t utterly dependent on one another, they can still be enriched by mutually beneficial trade agreements.
Even without people regularly travelling between the worlds, this network of trade agreements would require some sort of governing body to make sure the contracts are honored.
Unless you have a method of interstellar travel (whether FTL or not) that is both fast and somehow bypasses exponential energy requirements, it’s doubtful that shipping any material good between star systems would ever be worthwhile. One possibility perhaps would be a “lightspeed jump” method of travel where you somehow turn a ship and it’s contents into a massless form of energy that travels at C and then reforms at it’s destination. Or a drive that somehow decouples most of a ship’s mass, allowing it to accelerate without using much energy. Unless it’s some sort of uber-valuable unobtainium like magnetic monopoles or strange matter, there’s nothing made out of ordinary atoms that couldn’t be mined or synthesized locally for vastly less effort than boosting a shipment to .99C.
As mentioned upthread, the main point of an interstellar empire would almost certainly be ideological or political. Either to enforce a fanatic ideology or to preempt the existence of such.
Joe Haldeman, in his excellent The Forever War, deals with this very interestingly. Due to time dilation in a centuries-long interstellar war, sometimes you’re the one with the M-16 and your alien foe just has a rock; sometimes it’s the other way around.
Except that that’s FTL travel: you can make a round trip in less time than a beam of light through normal space can. The point of the OP might be rephrased as “Is an interstellar state possible without fast interstellar travel?”.
It depends on what is meant by ‘empire’. Phyiscal control of such far-flung colonies will not be possible; at most, what you would get is memory of a shared ancestry.
This would hardly matter in the slightest, since contact bewteen them would be mostly trifling.
Interstellar warfare for gain is also an absurdity - it would be pointless in the extreme, since there is nothing that could possibly be worth looting, and any invasion force would of necessity pass out of the invading planet’s control.
Nope, there will always be undiscovered details. Now, as time goes on, those undiscovered details will get more and more obscure, but you can never tell when something practical might poke its head out of the obscurity.
I think the most plausible model for interstellar trade, absent some sort of FTL or other magical propulsion system, would be a trade in information. Whenever a world comes up with some important scientific advance or other piece of information, they radio it to all of the other worlds. Yeah, it’ll take years to get there, and it’s possible the other worlds will independently make the same discovery meanwhile, but occasionally it’ll be something new, and those times, it’ll be very valuable. Or the valuable information might not necessarily be scientific, either: Suppose the next Shakespeare is born on one of the worlds, you could send out all of his plays and poems, too. But if you go against the wishes of the capital planet, they cut you off from all transmissions, and instruct the other vassal planets to do likewise.
It worked, however, for both Persia and Britain, with similar effective transportation time issues. If the Crown, for which you have much respect and affection, rarely (like once every decade) makes a request/issues a ukase, you’re likely to comply on the rare occasions it does, figuring it has a good reason even if you don’t know it.
What Commonwealth political writers call “responsible government” is what would work – a single sovereignty, but implemented in each system by leaders answerable (“responsible”, hence the term) to the local populace but adhering to a common set of goals, ideals, and constitutional norms. It doesn’t mean that an appointed governor and council answerable to the central government are irresponsible, only that the “responsible government” is held responsible for its acts by the people it governs on a daily basis.
Well, if you want to invent all kinds of stuff. Even the Roman Empire, though, lost the outlying provinces in not that many centuries. If AIs are actually intelligent, they can be swayed by appeal to their self interest. If they are not, they might be convinced that the most loyal thing to do would be to let their subjects go.
If there is a perfect defense, the occupiers will be out of luck. And even with equally matched weaponry, there may not be evenly matched generalship. Some wars in the past were decided by superior technology, but many, like the Revolution and the Civil War, were decided by better tactics.
Then a little kid can pull the plug. If the robots are controlled by humans, then the human can be turned. If not, see above.
If they are programmed to have no self interest, then they won’t even if they are intelligent. And if part of their loyalty programming is to never, ever let their subjects go, they won’t. If they are designed that way, they’d still sit around demanding everyone be loyal to the Empire even if the rest of the Empire was destroyed.
You say that matter-of-factly.
If the robots are controlled by humans, then the human can be turned. If not, see above.