A Visualization of Galactic Settlement
centauri-dreams.org
centauri-dreams.org
That being said I agree with your main point. The difference in worldview, ethics, where man sees himself in the universe over the course of our history (let alone pre-history) has taken dramatic and difficult to model changes.
Imagine the worldview of the builders of the Great Pyramid vis a vis our own. (And then remember that Cleopatra was far closer in time to us than them.)
I think it is worth noting that a new settlement will not be completely cut off from its parent. I imagine a new settlement around Alpha Centauri will be greedily consuming Earth media for quite some time, delayed by just a few years, until it progresses far enough for its own exotic drammedys to be consumed by Earth.
Any technological advance in interplanetary travel speed or new technologies of renewable and easy source of energy, would promote expansion. The new arrivals to an empty planet could start all over again, claim the resources as theirs, organize their own laws. And if they are overcome somehow move to other planets and start all over again...I think there is wave coming our way if we think about it.
Thing is, we still don't know yet what matter and energy actually are. We still don't understand the nature of spacetime. We have a lot of physics to discover. Those other civilizations might have discovered physics in different order. They might be communicating using phenomena we have no idea exist.
It's not right to assume that advanced alien civilizations will be using any technology similar to ours.
For an interstellar beacon signal radio is pretty good. Lots of natural phenomena are radio sources, CMB is radio, and a lot of things opaque to visible and near visible light are transparent to radio. So a radio beacon has a good chance of being detected just because any civilization that discovers radio astronomy can stumble across it.
The idea that SETI would ever detect I Love Lqwynngh'tch reruns from an ETI has always been ludicrous. Even our most powerful radio telescopes (by sensitivity) wouldn't be able to detect television or radio broadcasts even a lightyear out from Earth. The only interstellar signal we (or another civilization) will ever detect are very intentional directed signals.
If you had an omnidirectional radio source detectable from interstellar distances you could use it once as it would fry itself and anything around it pretty quickly.
Science fiction is full of sentences of the form, “The Klaatu were an alien race who colonized the galaxy a million years ago but have since moved on.” I always roll my eyes at this. Almost no matter what the Klaatu are or what they care about, there would be some group of them remaining. And the only Klaatu we would see would be the descendants of the ones who stayed. Giant galactic civilizations made of individuals are unlikely to make coherent collective decisions with no dissenters for the same reason our single planet (with much less serious communications obstacles) never makes unanimous collective decisions.
Point stands.
In fact, since spacefaring presents a threat (kinetic bombardment) to any planetary-bound species, then that majority who choose to enter the simulation may want to expressly prevent the minority from leaving the planet.
I think the metaphor to look to isn't necessarily even human civilizations spreading around the globe; it's life spreading through the planet to colonize every niche out of which the slightest scrap of energy can be extracted.
It's an interesting question. How do people maintain control now? In general, it is not through physical control. We have institutions, we have "manufacturing consent".
Manufacturing positive consent for a billion-year project is - obviously - a completely different kind of problem.
But to give you some hints, breakaway civilizations would likely happen all the time. Every space program has issues with astronauts not following orders simply because the astronauts internalize the idea of "what are they going to do? Come get me?" This is frequently talked about in settings where they are discussing Moon and Mars colonization. A Martian colony won't really belong to the US/China/EU/whatever for very long. I'd expect something very similar to Red Mars/The Expanse.
Another big reason for this will simply be time of light communication delays. Between Earth and Mars that's 8-15 minutes one way. It is highly impractical to control a territory when communication takes so long, they will effectively become independent. We've seen this historically too. Colonies operate drastically differently than their home countries. Being so far away it is difficult to communicate and cultures will diverge, especially considering that their day to day lives will be drastically different. Different needs creates different cultures. But luckily this distance also makes war difficult between two planets. You have months to respond.
From the script to Casino:
> Every couple of weeks I used to send Marino back to the bosses with a piece of what I made.
> Not a big piece, but fuck them, what did they know? They were fifteen hundred miles away... and I don't know anybody who can see that far.
On the other hand...
> Between Earth and Mars that's 8-15 minutes one way. It is highly impractical to control a territory when communication takes so long, they will effectively become independent.
This is totally wrong. Between Earth and Earth, empires have exerted effective territorial control while communication one way took weeks. A 15 minute delay in communication is meaningless. The problem is the difficulty of traveling, not of communicating.
That's because the effective territorial control was not exercised by the central government of the empire, but by territorial governments that were on the spot and that had pretty much complete authority to act on their own initiative without getting permission from the central government. They only had to meet very general policy goals. So the speed of communication with the central government was not relevant to the effectiveness of the territorial control.
The question is whether a territorial government on, say, Mars would have the same loyalty to the central government on Earth that, say, British territorial governors had to the British empire. Without that loyalty on the part of the territorial governments that are on the spot, there is in fact no way for the central government to effectively control territories.
Moreover, Mars would probably be utterly dependent on earth for multiple generations.
Those tactics only work when backed up by a credible threat of overwhelming force. I do not think the Earth will be in a position to bring overwhelming force to bear on a Mars colony. It's a lot harder to do that across tens of millions of miles of space than it is to do it across an ocean. And even across oceans on Earth it often doesn't work.
> Mars would probably be utterly dependent on earth for multiple generations.
I'm not so sure. We have barely even started exploring Mars; we have no idea what resources exist there. We are still discovering new resources here on Earth; I would expect that humans on Mars would be doing the same there.
Probably not. The reason Mars colonization is difficult is because they have to be self reliant. It isn't like expanding in the past where people could live off the land or barter or steal from the native peoples. There are no natives on Mars. There is no native vegetation nor is the land adequate for farming/cultivating.
In the past colonies could rely on these things and exploit them. Mars is very different. If you aren't self sufficient on Mars you will die. Period. Astronauts visiting Mars, just visiting, will have to figure this out too because they can't just land and come back. They have to wait a full year for the planets to realign (this is also why it is difficult to subjugate Mars because it isn't just about the travel time, it is about the orbits being aligned plus the travel time).
This actually shouldn't be true for much longer. The only reason it's true now is that we don't have spaceships that can produce constant thrust for the entire trip; our ships spend most of their time in free fall, which, as Robert Heinlein pointed out decades ago, is the equivalent of floating down the Mississippi on a raft. As he said, what we need are the equivalent of sailing ships: ships that can put out a constant thrust, even if it's small, for an entire trip. Even a thrust of 1/100 gee, which is well within our technical capability if we get serious about things like ion drives, would greatly reduce trip time to Mars (and would reduce trip times to more distant planets even more, since the advantage over free fall increases as the distance increases) and would open up a lot of options for travel that we don't currently have.
Note that this doesn't change the fact that humans on Mars will have to be self-reliant; payload mass is still payload mass and a spaceship just won't be able to carry enough of it to Mars to supply life support for any length of time staying there. Sending unmanned missions in advance might help, but I don't think even that would be enough.
Sails don't do that. In terms of propulsion, they're exactly the same as pole-less rafts. Ever heard of being becalmed?
The propulsive force is not as controllable as it is for a low-thrust rocket, true. But Heinlein was not claiming an exact comparison.
> they're exactly the same as pole-less rafts.
No, they're not. Pole-less rafts don't have sails.
> Ever heard of being becalmed?
Ever hear of missing the point?
Yes, sailing ships can be becalmed. But they can also not be becalmed. And sailing ships that were not becalmed created a worldwide system of trade. Pole-less rafts would not have been capable of doing that.
And as for robotic warfare, I'll give the same answer to everyone that asks how guerillas fight tanks and jets. 1) you can't rule the dead, 2) international trade looks down upon countries that commit genocide, 3) genocide is typically pretty expensive.
Yes, indeed.
> Your burn rate will increase dramatically depending on Mars/Earth alignment.
Why? I am not talking about keeping trip time constant. I am just talking about significantly reducing trip time compared to free fall. That is easily done with a low thrust ion drive; even a hundredth of a gee makes a significant reduction in trip time, and the longer the distance, the more the reduction in time even holding the thrust constant (since the trip time now increases only logarithmically with the distance instead of linearly). And that makes trips more feasible even when the planets aren't in alignment.
> even with the best technology we can see ourselves building within the next decade or so we're talking 3 months on a good alignment
Now it's you who aren't conferring much confidence in your knowledge. Below are some numbers (travel times are one-way). I've even included numbers for 1/1000 gee to show that even those numbers are much better than the free-fall numbers.
Closest approach: about 60 million km (6 x 10^10 m) Free-fall travel time: 180 days 1/100 gee travel time: 18 days 1/1000 gee travel time: 57 days
Furthest away: about 400 million km (4 x 10^11 m) Free-fall travel time: 1200 days 1/100 gee travel time: 47 days 1/1000 gee travel time: 148 days
The free-fall transit time for closest approach is taken from the Wikipedia article on free-return Earth-Mars trajectories; I have used the shortest time that appears to have a reasonable return trip (though the return trip transit time is longer). [1] Free-fall transit times for furthest away are taken by multiplying the closest approach time by 6.67, which is probably somewhat of an underestimate (it assumes straight linear dependence of trip time on distance, without confirming that there actually is a viable transfer orbit with that transit time).
1/100 gee and 1/1000 gee transit times are obtained by using the formula t = 2 sqrt(d / a), where d is the distance and a is the acceleration. This formula assumes constant acceleration to the halfway point, then turnaround and constant deceleration the rest of the way. (I also adjusted the units in the answers above to days instead of seconds, which is what the formula I just gave gives; I rounded up all fractions.)
I have ignored orbital maneuvers and takeoff/landing at both ends for all travel times.
https://en.wikipedia.org/wiki/Free-return_trajectory#Earth%E...
> Columbus was on the sea for 36 days
Which was by no means the longest, or even a particularly long, voyage for the time period. Vasco da Gama was at sea for more than three months at a time during his voyage around Africa to the Far East and back. So was Magellan during his round the world expedition.
No, many of the British colonies had the ability to become independent fairly soon after being colonized. The key variable wasn't how capable the colonists were but how interested Britain was in controlling them, and that varied widely from colony to colony, depending on who in Britain had to exercise the control. Some, like the British peers who had ownership interests in New York and Virginia, were control freaks and wanted to exercise all sorts of detailed micromanagement of their colonies. Others, like Penn with Pennsylvania, basically let them do whatever they wanted and didn't bother much about it. And even in colonies like New York and Virginia, once you got away from the coastal cities or river ports that were easily accessible to British ships, the level of British control dropped drastically. The British couldn't do much at all about up-country backwoods farmers and trappers, who basically didn't care what the British or the colonial governments did since it couldn't really affect them.
What didn't crystallize until the 1770s was the political unity between the colonies behind an explicit declaration of independence. Which was, in large part, a product of the British, after the end of the French and Indian War, deciding that the colonies had already gotten too independent and needed to be reminded that they were still British subjects. Which didn't work out very well.
> that more to do with Napoleon for South America and the rest of the world wanting to take Britain down a peg
All of which happened after the US had already become independent. So it's irrelevant when looking at how the US became independent.
It is true that the British were still dealing with the French in Europe and that this limited their ability to project power in America during the US revolution. (The Americans also took full advantage of this by allying with France.) But that just illustrates my point: empires aren't omnipotent and can't just magically project power whenever and wherever they want to.
I don't think that's true, since, as godelski points out, in a salient historical case where the colonies did not respect the home empire's laws--the United States of America--the home empire did not have the resources to overrun them. The British ended up learning similar lessons in South Africa and India later on.
I think the main reason colonial governments respected the home empire's laws is that the territorial governors and their personnel were loyal to the empire; they believed in the empire and its aims. When that loyalty goes away, as it did in the USA, the home empire can't do much about it.
> The same will be true of any off world colony for the foreseeable future.
You must be joking. If the British empire was unable to enforce its will on the United States, with only an ocean separating them, how could an Earth empire possibly enforce its will on a Mars colony, with tens of millions of miles of space separating them?
1. The US territories existed in a time before our current technology which allows one to send drones to other planets
2. The US was heavily settled by the time it gained independence it could hardly be called a colony anymore at that point.
3. I said the foreseeable future, not indefinitely. Sure by the time there are millions of people on another world with their own economy, militias and legal tradition going back centuries that territory could make a bid for true independence but that won’t be the case for centuries at best. Any territory doing so anytime soon will seriously lack the industry and manpower to even hold their own territory against a large Earth based nation capable of colonizing other worlds.
I think it is you who must be joking here
In other words, you redefine words to avoid admitting any flaws in your argument. The United States was a territory of the British Empire. The British Empire failed to "overrun" them when it got "upset enough" (your words). So your argument fails for this case. You can't change that by redefining words.
> The US was heavily settled by the time it gained independence it could hardly be called a colony anymore at that point.
Excuse me? Being "heavily settled" in no way prevents a place from being a territory of a foreign empire. The population of India during British rule was far larger than the population of the British colonies in North America in the 1770s. That didn't stop India from being a territory of the British Empire.
> a large Earth based nation capable of colonizing other worlds
Colonizing other worlds is a lot easier than controlling them from tens of millions of miles away once they're colonized. The former just takes enough people willing to make the trip and a spaceship that can make the journey. The latter takes the ability to project overwhelming military force across that distance, which is a lot harder.
Also, I am not saying that, for example, a Mars colony must become independent. I'm simply saying that whether or not it does will depend on the motivations of the people in the colony. If those people remain loyal to Earth, the colony will. If those people stop being loyal to Earth, they will start acting independently, and there won't be a lot that Earth can do about it.
Firstly, this seems obvious. The conclusion of "even really slow spaceships will colonise the galaxy given enough time" is almost mind-numbingly banal.
Secondly, the parameters seem to be chosen in order to produce an "interesting" propagation pattern, rather than based on any actual data or guesstimates (I know there is no data, but making shit up is no substitute).
Thirdly, it doesn't answer the big important question of "where are they?" (as fnord77 asks). Saying "even really slow spaceships will colonise the galaxy given enough time" brings us immediately right back to "how much is enough time to colonise the entire galaxy?" which they then say is ~1 billion years.
Fourthly, but they're not here. So the answer to that question must be "over ~10 billion years". So either the simulation is wrong (because it takes longer than ~1 billion years) or it's pointless (because the only other explanation is that there has been no such colonisation effort, so why are we modelling it?). This wasn't addressed at all.
Fifthly, this assumes that all solar systems can be colonised, and will produce another colony ship 100,000 years later (for inadequately explained reasons). Given that we know a fair bit about the actual galaxy (though the simulation doesn't look anything like our actual galaxy), why didn't they run the simulation on our actual galaxy, and exclude the stars that we know can't be colonised (because red giant, etc)?
Finally. Is this the state of cutting-edge research on SETI? This wishful-thinking make-believe "look what I made Mum!" stuff? If this was a bootcamp dev showing off their WebGL modelling demo, I'd be impressed. 'nuff said. Sorry to be harsh, but... really? this is it?
I mean, when all you have to work is literally nothing all you can do is speculate. It is disappointing but what can they do but throw everything at the wall and see if it sticks.
IT is a an interesting question, but it seems weird to fault the article for not being something different.
Alternatively, one could argue that all of this data is worthless in predicting the industrial capacity of spacefaring culture, at least 100,000 years more advanced. Im guessing this is why they didn't bother.
I also don't believe a species that masters slow interstellar travel would care about stars and planets. Most of the mass which could be exploited by life is floating between the stars in the form of comets and if you could "live off the land" out there you could create millions of miles of apartment buildings and shopping malls.
Why trek into an inner solar system and build yourself a space shuttle that can land full of fuel and then take off when you are settled into a space lifestyle?
> Why trek into an inner solar system
Why venture off to unknown shores to build yourself a farm when you're settled into a comfy European lifestyle?
Although we only have ourselves as a data point, I think that natural curiosity is a strong evolutionary trait that we developed, and it's not a huge stretch to assume that other lifeforms would develop the same curiosity.
“A nice place to visit, but you wouldn’t want to live there”
> Technology persists in a given settlement for 100 million years before dying out
Seems wildly speculative to me. Our own civilization has only been around for a tiny fraction of that time and future prospects are already looking pretty uncertain. And if we lived in a galaxy where civilizations had this kind of longevity, one would think we'd see some evidence of potential signals out there.
My own pessimistic take on the Fermi Paradox is that life and intelligence may not be very unique but there is no reason for them to be long-lived either. Most civilizations are probably just a "flash in the pan", existing too briefly and separated by too great a distance to ever come into contact with another one (or even learn of another's existence).
...and maybe not even within the four dimensions with which we're most familiar.
> Technology persists in a given settlement for 100 million years before dying out;
Those are... uh, some kind of numbers. Really not sure what they think they are simulating here, but it sure does not sound like anything we'd expect to happen in reality.
Is it that you think the technological civilization duration is not conservative? Remember we're talking about a civilization that can cross the galaxy here. They can show up in a star system and throw habitats across any planets, moons, or asteroids they find appealing. They can also set up whatever number of space structures they want. What exactly do you think is so likely to utterly extinguish this species in every star system within 100M years?
The long duration between colonization events is not only highly conservative, it also functions here to allow any particular civilization to be pretty irrelevant. Even if some crazy war breaks out within a star system, a single surviving habitat is enough to allow the next colonization to still occur.
So, yeah? It all strikes me as a pretty normal conservative estimate intended to let them figure out some kind of reasonable lower bound here. All pretty normal stuff.
And it doesn't even need to be a single civilization. You only need a civilization to exist capable of launching a new colonization venture every 100k years, or whatever the average rate they assumed was.
That would be earth at the current point in time. Given 100k years I’m sure we could fabricate a huge colony ship, and accelerate it to 10km/s. What we won’t be able to do is throw up habitats all over the solar system.
By that point all your tech is thousands of years old. It seems unlikely it’d be capable of doing more than drop you off on whatever planet you were aiming for (or keep floating around, if it’s a lifeless husk).
Compare the efforts it takes to talk to Voyager vs SETI: unless the aliens are talking to us in the way we are looking for we're not likely to see them.
I won't even get in to the blithe assumptions about the ease of interstellar travel; Charlie Stross has a lot to say there and all said better than I could.
So the next hundred years of human advance, I expect, will bring similarly transformative changes in the ways we communicate and the shape of our "technosignature".
Our expectations for what other species might be doing don't seem to be informed by the things we know we've done.
We are basing what we consider natural phenomena on our observations of the galaxy.
If we were to flip the assumption from life being rare to life being pervasive, what assumed natural phenomena could in fact be evidence of life?
There is precedent for this on Earth. We are just startign to discover how much The Amazon rainforest is actually a human creation and basically a massive multi-generational bioengineering project.
This is not a serious position fo mine, btw, I know that we can track most astronomical phenomena back to fundamental laws of nature.
But equally there are some massive astronomical myseteries (dark matter/energy, certain stars being more/less common than expected etc) and I can't quite dismiss the wonder that our baseline assumptions have been tainted by this assumption.
There's your Fermi paradox, we live in a dumpster pile.
Lines up great with my self-esteem.
It looks like using only old technology we can detect the signal and identify it as a artificial signal, but it would be very hard / impossible to decode.
Granted, you'll not be able to differentiate between them, only that they exists. And at this point of searching for those signatures that's all you need though. Also Marconi was listening to lightning strikes generating radio waves using his radio, and that was over a century ago. Lightning strike generates radio waves all over the spectrum, so we had this capability right from beginning.
I mean sure, sci fi mode engaged, aliens may have ascended our own physics and may use quantum entanglement or subspace for communications and the like, in which case we wouldn't know. And our own signals too will get weaker and garbled over time; I'm not sure if even our own radio broadcasts 100 light years away are discernible from the background radiation of all the stars.
https://en.wikipedia.org/wiki/The_Millennial_Project:_Coloni...
> The Millennial Project: Colonizing the Galaxy in Eight Easy Steps by Marshall T. Savage is a book (published in 1992 and reprinted in 1994 with an introduction by Arthur C. Clarke) in the field of exploratory engineering that gives a series of concrete stages the author believes will lead to interstellar colonization. Many specific scientific and engineering details are presented, as are numerous issues involved in space colonization.
I find the cover image of a green galaxy is very inspiring!
2) Due to the nature of exponential growth, we will eventually feel a population crunch when reproduction overwhelms the rate of expansion. This is true even if we invent FTL ships. The crunch would be delayed (perhaps for millions or billions of years) but it is inevitable.
Civilizations aware of imminent extinction-level events may choose to do that, similar to how shipwrecked sailors may fashion a raft and "risk it" in the off-chance they survive.
Presumably the people that do this do not think ship life will be that bizarre.
I’m frankly more concerned about the sustainability aspect than how daily life will work.
But I don’t think it’s too far fetched. Imagine a VR system that doesn’t require wearing a helmet and can be displayed in physical space. And/or a Matrix-style direct jack into the brain. Any environment you can think of, easily accessible. Doesn’t seem that bad to me.
Beyond that, A lot of people already spend 10+ hours staring at screens here on Earth...
And don’t forget that you’d be in space with tons of other colonists too.
If the ships are big enough, living on them approximates living on a continent / planet…
Though, honestly, humans are terrible galactic conquerors. The artificial life that we create will be the ones taking over the galaxy.
(in case anyone scrolling by is looking for additions to their to-read list)
Exactly. A galactic version of "core wars". If we leave any trace at all it will be our machines. Future life will resemble 3D printers in search of raw materials, not GI tracts in search of food, spores that will survive billion year voyages with infinitesimal chances of success.
But life on earth has been going on for hundreds of millions of years so I don't think we'd find any traces of it.
https://en.wikipedia.org/wiki/Timeline_of_the_evolutionary_h...
Generally I'd say that the notion of a Von Neumann machine is so obvious and so effective that there's something really wrong in our guesses on how widespread intelligence is.
One example: "upload" and "simulation" do not have any predetermined relationship to the material behavior of a species engaged in it. The mapping between agency in any presented reality and the species-consensual one is arbitrary and the distinction between simulation and reality might just as well be framed as a question of sensorium cum UX.
Very very little can be extrapolated upward from our own limitations and constitution either as individuals or societies or species.
An even deeper example: fundamentals like the relationship to time may be radically different. It may not just scale, it may be fractal; and the notion of what constitutes agency and the locus of selfhood and identity, and hence self-interest, may be distributed emergent and predicated on an interplay between ant-and-colony at multiple levels, each of which is fully "conscious" and intentional in the sense we understand those things, at different time scales.
What does a third grader know of amortization?
We are not even out of the womb as a species.
Taking into account ship ranges and settlement lifetimes produces very different results (15:36 in the video).
E.g. to escape from violence, conflict and war.
Would an advanced civilization find value in colonization? Very likely -- colonization (biological or machine) is likely the cheapest way to explore another stellar system in detail, with explorers manufactured or born in situ.
1. Speeds are likely to be much higher. We largely rely on chemical propulsion plus gravity slingshots. For a sufficiently advanced civilization you're likely to concentrate a star's power to provide significant outward propulsion (and braking!) without the mass concerns of carrying reaction mass;
2. Once you've built one of those starships, it will likely continue on its journey after stopping at a new system to colonize and resupply. It's not clear to me if the simulation assumes this. Given the time frame of 1B years it seems not;
3. Stars in the Milky Way rotate at different speeds. Like in a few hundred thousand years we'll have a new closest neighbour for awhile. This potentially increases spread as the colonized systems drift further away extending their reach over time;
4. The simulation just looked like a collection of stars rather than, say, a spiral arm galaxy.
So a realistic timeline is closer to 10M years than 1B years.
I'm firmly in the camp that believes the speed of light is a hard limit. FTL drives and variants (eg wormholes) just seem to be wishful thinking by people who don't understand function domains (eg negative mass). Assuming that, a galaxy-spanning civilization is unlikely to be a civilization in the sense we understand it given that it might take you >1M years to cross from one side to the other.
That's not really a problem for detecting such civilizations as the source of detection isn't likely to be EM transmissions (as the SETI program began looking for). Instead, it's likely to be the IR signatures of Dyson swarms.
Short version: in space, the only way to cool down ultimately is to radiate that heat away into space. That radiation is completely dependent on the temperature of the object radiating heat. For any normal range temperature that's firmly in the IR range. So, if a star has a Dysown Swarm, it'll shine incredibly brightly as an IR source with a very low amount of visible light.
Can you spot one such star? Possibly not. But an entire galaxy? You're likely to be able to see that from 1M+ LY away, easily.
Given the small amount of time this would take to eventuate, in cosmological terms at least, the reason we haven't been able to detect any highly-advanced civilizations within our light cone is quite simple: there aren't any.
Also, I don't think it was meant to be a fastest or even nominal case simulation. It could clearly be run with different inputs