"Realistic" FTL

[Formless]

Xeriar, your argument only works if:

1) colonization takes place after civilization has reached the point where individuals can have "lifespans comparable to that of stars." ()

and following from that

2) the colonizers are motivated to try and stay in touch with the mother civilization.

To the first, while it is infinitely more plausible than FTL, it is not a given; I don't know about you, but its seems to me to be a whole lot easier to just construct a seeder ship(s) (especially if we throw in Von Neumann self replication ) and start spreading humanity. But I could be wrong on that point, so lets assume for the sake of argument that you have already created a transhumanist utopia that gets around those pesky little things like mortality using, say, genetic engineering, robotic bodies, or good old minds on a chip. Does that mean that the colonizers are necessarily going to want to stay in contact with their parent civilization?

No.

In fact, it would be rather detrimental to your argument because both of the two approaches for drastically extending lifespan (extending the life of the body with gene tech or robot bodies or flat out uploading peoples minds to a computer) eliminate one or another of the historical factors for colonization; specifically, population growth and population density * .

Now, in a civilization where your physical body can live for tens of thousands of years or is otherwise functionally immortal, then its a safe bet this civilization has already mastered the art of population control. The only conceivable reason people in such a civilization would have for leaving their home system is if they want to get away from their mother civilization for whatever reason (civil unrest, war, discontent of some kind-- possibly with the population controls themselves ). Which means a cultural divide is already there, and the colonization would be a symptom of (or at least an outlet for) it. Plus, any colony that gets started will probably experience relatively large growth compared to its parent civilization due to the ready availability of space and resources. This growth will mean that pretty soon, the majority of the population isn't going to have any connection to the parent civilization at all.

Think about how different the U.S. and the U.K. are. Now imagine how different they would be if communication never improved past snail mail.

Furthermore, if you go for the mind in a chip approach, you have now effectively eliminated population density from the equation. The efficiency with which this civilization can use the space it has to house people will go up by so many magnitudes as to render colonization a pointless exercise except as a way of creating a back up copy for disaster insurance. If they even go through with it, then there is no need to keep in contact with friends back home-- you can just bring along copies of them and you will never know the difference. Freaky, but that's how that kind of civilization works.

And of course, if you use the classic setting with humans colonizing worlds and living lifespans no longer than modern Earth, cultural unity is a lost cause. But you knew that.

* well, historically the third factor would be greed... but considering how ungodly expensive it is to move materials interstellar distances, I think we can agree that this isn't going to be much of an issue anyway. Not without inventing some really, really contrived bit of handwavium.

[Ariphaos]

Xeriar, your argument only works if:

1) colonization takes place after civilization has reached the point where individuals can have "lifespans comparable to that of stars." ()

To the first, while it is infinitely more plausible than FTL, it is not a given; I don't know about you, but its seems to me to be a whole lot easier to just construct a seeder ship(s) (especially if we throw in Von Neumann self replication ) and start spreading humanity. But I could be wrong on that point, so lets assume for the sake of argument that you have already created a transhumanist utopia that gets around those pesky little things like mortality using, say, genetic engineering, robotic bodies, or good old minds on a chip.

It doesn't need to be a utopia for everyone, just the people that matter for our purposes. Anyway...

Ignoring the fiction license for the moment, the issue here is when we would actually launch an interstellar colonization effort. Put a man on Mars by 2030, set up a colony by the end of the century and begin terraforming - that's a century of progress when we are already beginning to find rather clever means of peering into the mind, genetic therapy, whatever.

Seeder ships actually become rather inefficient in such a scenario, and rely far too much on finding a habitable biosphere. There is no true need for such other than the desire for humans to look and be 'human'.

and following from that

2) the colonizers are motivated to try and stay in touch with the mother civilization.

Does that mean that the colonizers are necessarily going to want to stay in contact with their parent civilization?

No.

In fact, it would be rather detrimental to your argument because both of the two approaches for drastically extending lifespan (extending the life of the body with gene tech or robot bodies or flat out uploading peoples minds to a computer) eliminate one or another of the historical factors for colonization; specifically, population growth and population density * .

Now, in a civilization where your physical body can live for tens of thousands of years or is otherwise functionally immortal, then its a safe bet this civilization has already mastered the art of population control.

Considering the quantity of resources in a star system, no. There's no absolute reason to, for one.

The only conceivable reason people in such a civilization would have for leaving their home system is if they want to get away from their mother civilization for whatever reason (civil unrest, war, discontent of some kind-- possibly with the population controls themselves ).

Wanderlust? A desire to discover? Literally speaking, seeking out new life and new civilizations?

Which means a cultural divide is already there, and the colonization would be a symptom of (or at least an outlet for) it. Plus, any colony that gets started will probably experience relatively large growth compared to its parent civilization due to the ready availability of space and resources. This growth will mean that pretty soon, the majority of the population isn't going to have any connection to the parent civilization at all.

Think about how different the U.S. and the U.K. are. Now imagine how different they would be if communication never improved past snail mail.

You are comparing a pair of ancient civilizations with a race in which the entirety of human history and science is available with immediate recall. I find the claim that the results will be similar rather spurious - they may be, but there's no absolute need for me to write that way.

Furthermore, if you go for the mind in a chip approach, you have now effectively eliminated population density from the equation. The efficiency with which this civilization can use the space it has to house people will go up by so many magnitudes as to render colonization a pointless exercise except as a way of creating a back up copy for disaster insurance. If they even go through with it, then there is no need to keep in contact with friends back home-- you can just bring along copies of them and you will never know the difference. Freaky, but that's how that kind of civilization works.

That's only assuming people may want to be copied or have no protections against doing so. If you want to write it that way, great, but no reason for me to do so.

And of course, if you use the classic setting with humans colonizing worlds and living lifespans no longer than modern Earth, cultural unity is a lost cause. But you knew that.

* well, historically the third factor would be greed... but considering how ungodly expensive it is to move materials interstellar distances, I think we can agree that this isn't going to be much of an issue anyway. Not without inventing some really, really contrived bit of handwavium.

Or light sails using a miniscule fraction of their parent star's output.

One short story I never got around to finishing was about a light sail network spanning the Galaxy, with various far-flung 'peoples' making million-year pilgrimages to Earth.

Because they can.

[Junghalli]

Longer lifespans are likely to slow down cultural change for the simple reason that the older generations hang around a lot longer and keep influencing the culture. Imagine, say, the effect on our culture if people from the 1800s were still alive and many of them still occupied positions of power and influence. And if population stabilizes a population where accidents and suicides are the only cause of death that's stable will have a very low birth rate, which will dramatically enhance the effect. Not only do the old people hang around much longer, but much fewer new people are being created in a given year, decade, or century.

I don't really see why a high degree of cultural conformity between different worlds is all that important anyway. As long as their governments agree on certain common goals you have your "empire". And I would think from a storytelling perspective cultural divergence is cool - lots of different worlds for the author to explore.

[Ariphaos]

Exactly. The main idea is that you need to be on at least cordial terms with your neighbors. You don't need to be building the same sorts of VRs or whatever, but you do need to agree that if someone starts going nuts with sunshine and happiness, they need their butt kicked.

Having a lightsail transfer arrangement between neighboring star systems would also be nifty, especially as many would be suspicious about beaming their awareness to someone else's receiver.

[Darth Hoth]

There is nothing to say you cannot do this in a fairly "hard" setting, if you make it extreme enough; just build thousands of Dyson Sphere equivalents and wait a few millennia

Of course, that does still leave the annoying little engineering problems of getting that energy into a form dense enough to fit in the 100 meter warp bubble and having the ship not be turned into plasma from its own waste heat when you flick the switch. Both will require serious magic.

Obviously, but I was under the impression that we were discussing power generation and its consequences, here. Raptor wants FTL, which by definition needs to include "magic", but wants it as realistic as possible. By one definition of such, using a mechanism as close as possible to proposed theoretical such of real science and invoking the minimum of magic that one needs for it to function might be it. Generating power on that magnitude is not necessarily impossible, it is managing it that screws up.