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Paul Krugman's 1978 Theory of Interstellar Trade
jerryasher recommends Paul Krugman's blog at the NYTimes, where he introduces a paper he wrote, The Theory of Interstellar Trade, with tongue very much in cheek. Some packrat academician was kind enough to send him a scan, because "back then academics did their work with typewriters, abacuses, and stone axes." Abstract: This paper extends interplanetary trade theory to an interstellar setting. It is chiefly concerned with the following question: how should interest rates on goods in transit be computed when the goods travel at close to the speed of light? This is a problem because the time taken in transit will appear less to an observer traveling with the goods than to a stationary observer. A solution is derived from economic theory, and two useless but true theorems are proved... This paper, then, is a serious analysis of a ridiculous subject, which is of course the opposite of what is usual in economics."
The shovels and how much digging you had to do that academy. ;)
-Aegis Runestone-
Just some thoughts:
On a note, I recall reading that section of the book. It comes at the end of "island in the Sky", a remarkably sober book about colonizing space (sober in light of crazier scifi/colonization books). For some reason I read it first and the pessimism of the article stuck with me, setting the tone for the whole book. That's not bad--our views about space travel and the future need pessimism, but I felt that it was the overriding theme.
In the end, there is no free lunch. While you could predict that interstellar travel would change time preference for some, there are a few caveats to make here:
1. Perhaps travel is so expensive that the change in time preference for some doesn't impact the market as a whole. If you have a vanishingly small group of people pushing the discount rate down, does it affect the prevailing rate? You could argue that the income effect of the billionaires of the world might be analogous. While Bill Gates may have the latitude to spend more money on small purchases than they might be worth to him systematically, that does not do much to change the price I pay for those same products.
2. Travellers will face a STEEP opportunity cost. There isn't any other way to describe it. They may (as the article in "islands in the sky" suggests) spend their wealth ENTIRELY on acclimating themselves to a radically different world or insulating themselves from that new world. In other words, this would be like taking a trip from ancient greece to the Soviet Union. You don't speak the language, you don't understand the culture, the medium of exchange, almost everything. You would be lucky if you weren't put in a circus or a museum.
3. In the longer term, risk dominates. Inflation risk and default risk historically rise to 1.0 as time marches on. There are vanishingly view equity or debt instruments that are still valid from 200 years ago. they exist, most notably in the low countries and england, but they are few and far between. What happens in the event of hyperinflation, panics or fraud (although the last one could be accounted for given a persistent third party overseer)?
4. Adverse selection. This is a corrolary of the risk argument. What bank would be likely to write a contract to make an astronomical payment in the far future? A bank that is likely to be solvent that whole time (assuming the bank knows with certainty) might, but would be FAR less likely to do so than a bank who might default on the contract.
5. Explicit cost. While this might eventually become a non-issue, we have to be real about what is at stake. A long term space voyage is basically one way in the eyes of the company chartering the craft. Unlike a 767 from NY to London, when the space ship returns, it will be obsolete, or at least at the end of its viable life. Each trip presents a large fixed cost for the charter company. This may not translate directly as a large enough cost to a consumer if the flight manifest is big enough, but it isn't trivial.
Just some thoughts.
But I think that the concept of interstellar trade based on transports must be a joke. The only way we could possibly have interstellar trade is if we had "magic doors" which harnessed wormholes to provide instant transmigration of goods and services across vast space in constant (instant) time.
Any trade of the type O(distance) where distance is greater than the lifetime of any players involved is necessarily a non-transaction.
Just flush them out now. Mark me -1 flamebait for this, but this post will bring out the people insisting on the strict superiority of gold over other forms of investment. While in this case, gold in a safe place (or any other precious metal) would be a better choice over a possibly unmanaged and eventually insolvent investment fund, THAT DOESN'T MEAN that gold is always better or what not.
This has already been posted on a blog about economics specifically (aside from the freakonomics blog. Here is the link.
trade of the type O(distance) where distance is greater than the lifetime of any players
Should be:
trade of the type O(distance) where the time to cross distance is greater than the lifetime of any players
What does this have to do with the price of tea on Trantor?
As an aside, I'd suggest the example of aluminum. 200 years ago, someone might've suggested investing heavily in aluminum. After all, it was one of the most valuable metals in the world due to its scarcity. That person couldn't have seen Alcoa coming along, and the same goes for us and future technology. Who's to say what nanotechnology will be able to do in 200 years?
I just got nailed with an interstitial ad when trying to go to this article!
/. reader for me.
/.! Please don't go that route...
Wow, maybe I have been lucky before but that's a first for me. Also possibly the beginning of the end as a
Bad, BAD
"Can we agree that the plural of abacus is abacii?" Bonus points for where this quote comes from (or else hand in your geek card!).
Buy lots of antiques. Travel someplace while lots of time passes for everyone else. Then your antiques are older and worth more. Of course the big risk taken is if someone invents a time travel device and starts dealing in antiques while you're traveling through space.
God spoke to me.
Considering that 1 in 4 teenage girls already have STDs, those will be in high demand.
Source: http://www.breitbart.com/article.php?id=D8VBB9D00&show_article=1
Obama likes poor people so much, he wants to make more of them.
So... you're allowing the trader's society to have sufficient technology and resources to accelerate a shipload of titanium to virtually c, to navigate across instellar voids, and then decelerate again... but you also think that society will not have conquered aging?
That seems far-fetched to me.
And of course, once aging becomes an outpatient condition, then a species' horizon is going open wide again. Thinking in terms of centuries or millenia will not be uncommon.
The Mongrel Dogs Who Teach
As a budding economist, let me try to look at it objectively.
The theory of general relativity clearly proves that my sole experience on a hot stove even if for a minute can seem like an hour, while a friday romping with my GF those wonderful 30 mins would seem like 1 minute to me.
So, an external view and perspective of time is essential to calculate interest and charges.
The crew can think it took them only 1 day, but the the parties involved it meant waiting 11 days.
Take my example for instance: i thought my honeymoon was not even a couple of days old when it ended, but my hotel manager AND my credit card company AND my employer proved it beyond doubt that it had gone for 8 days ! (Damn those guys. If only they had allowed me to enjoy my timeframe...)
"Doing what i can, with what i have." ~ Burt Gummer
Hi my name is Prince Valtor Tazalutium the Third from the distant planet Nigeron 7. I have dispatched the fastest cargo ships in my fleet to Earth filled with the rich treasures of my home planet. However because of the vast distance between our two planets my ships will not reach Earth until I am long dead and therefore will not receive a return on my initial investment. As I have no heirs I am looking for one trustworthy stranger to buy these ships and their cargo en route to your planet. I am willing to sell them for $50,000.00 US DOLLARS. If interested please contact me at valtorlol@aol.com.
Seem to be something in cattle that can only be aquired thru mutilation. Then there is all that rectal probing. "Rednecks" from backwater parts of the south. All that plus they apparently have some kinda deal with the aluminum industry with all them tinfoil hats we need to keep our brainwaves intact.
What else could they want? One would guess they wanted shades for them big eyes and lots of sunscreen since the little grey bastards tend to walk around nekked all the time.
There's another subtle joke if you look at the dates on the references. I almost missed it.
... are quite common. We call them "stocks", which are in principle supposed to function in perpetuity, and on the timescales of most investing humans (begin investing at age of majority or shortly thereafter, begin selldown at age of retirement), a suprising number of them are. (Companies older than 80 years old are not terribly uncommon. If you count all the various mergers, divestures, and restructurings that didn't result in common stock investors taking a total bath, there are probably more companies around today that "remember" commitments made in 1899 than there are living people who were alive in that year.)
This is largely just a pointy headed clarification: interstellar trade would be impossible for a host of other reasons. We'll start with "There is nobody to trade with, and finding somebody to trade with would require the 12th century Catholic Church making a deal with Microsoft on behalf of the 28th century Catholic church, without of course knowing that Microsoft exists, what form it takes, or what it values."
Help poke pirates in the eyepatch, arr.
Uh, folks. The PDF is gone. Mirror?
Assuming these to hold true, and the first is the basis of all modern economic theory (and socialism), then trade cannot suffer imbalance from near-lightspeed or relativistic effects.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Cargo hold load: 0 tons.
Local investment: -long-term investments in variety of domains and countries, 100% of the capital.
Go there and back, collect percentage.
45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
Retrieve ships logbook. Compute delta t of ships department and arrival at ships origin and halve it.
Well, that may even be insightful -- in a wishful thinking kind of way, because nanotech won't work like you assume -- but it still solves the wrong problem entirely.
(And even then it doesn't necessarily solve it completely. A colony of robots can still spend most of its energy and resources just repairing the robots and building new ones, so that cost can still remain. Or worse yet, it may need more goods sent from Earth than some colonists would, because such robots would presumably be high tech and require lots of energy and a lot of different factories to produce. So it might still be cheaper to send a 20km ship full of colonists, which only need a couple of farms to live there.)
But, anyway, the thrust of TFA isn't "how do you build a colony for your people", but rather "how the F-word _do_ you make a profit out of it? Is interstellar trade even viable?" Even with robots, and without having to pay the crew or the producers anything because they're robots, you still face some non-trivial problems there.
E.g., ok, you put an order for, say, uranium from that far far colony. How do you know that you'll even still need it by the time you get it? How do you know that the price will still be OK?
If your colony is at, say, 10.5 light years away on Epsilon Eridani, or 12 light years away on Tau Ceti, and if you travel at half the speed of light average (accelerate to nearly C half the distance, then decelerate the other half), that's 31.5 and 36 light years respectively from the moment you sent the order by radio to the moment it lands on Earth. (10.5 or 12 years respectively for your signal to get there, 21 and 24 respectively for the ship to travel here.) That is, if they already have the mine and the surplus of that resource and everything. Otherwise you might have to wait more.
For farther away colonies, even more.
Historically there have been massive changes in demand within less time. Cloth went from a massive money-maker good to being "meh" to being outsourced to third world countries to produce. Coal was once _the_ fuel for any navy, and sometimes even (explicit or implied) military threat was used to open up markets to buy it from and coaling stations. (See Perry's expedition to Japan.) It took less than 30 years for everyone to switch to oil in their ships, and coal became of much less importance. Or once whale oil was the main lighting fuel, then some guy goes and discovers the light bulb. Grain was _the_ thing to have for millenia, and the wealth and military power of, say, Poland throughout the middle ages was based on being able to produce and export lots of it. Buggrit. Then it took less than a century for the bottom to fall off _that_ market, and nowadays the only countries which still have an agriculture are those who subsidize it. Etc.
It becomes even funnier if you want to build a colony for the explicit purpose of getting some goods from there. Let's say unobtanium wishalloy is the latest rage, you spot some unobtanium in the spectral line of a far away star, and plan to make a living out of it. Now you have the round trip increased by building those robots and waiting for that ship to get there, build the colony, get mining, and some time after 50 years or so you get your first shipment of it even for the nearest stars.
Will it still be needed? Will your company even still exist after so much time? What bank will give you a loan for that kind of thing?
And will your investors want your head rolling for that? Today's capitalism is obsessed by short term results, and thinks in quarters and years. (Maybe even justifiedly so.) Proposing to blow a huge chunk of money, with compound interest (one way or another: even if you have the money and don't take the loan, it must be judged against the interest you'd get if you just put that money in a bank and started _getting_ interest on it) on something which _might_ make you the big bucks in 50 years, will get Wall Street screaming for blood.
A polar bear is a cartesian bear after a coordinate transform.
...that he cited a paper of his from nine years in the future?
1. Specific elements/particles according to supply and demand.
2. Knowledge of what can be done with said elements.
When you have post human super AI and nano-tech then the cost of making things is zero once the elemental materials and energy are accounted for, that folds into just elements because energy is derived from elements (fusion or fission feed stock)
Knowledge can travel at light speed, or perhaps faster if quantum coherence becomes usable over interstellar distances, then the coherence of particle pairs will be consumed to provide instantaneous knowledge over any distance. Spreading particle pairs over such distances will take time but can be done in advance of their use.
The cost of knowledge will be proportional to the computational time required to create it, this will be determined by the size and speed of the logic engines assigned to the task.
Finding a means of trading knowledge for access to QC network bandwidth will be interesting. Perhaps knowledge will be free, but the cost of getting it in real time will not be, otherwise you would need to wait for it to propagate at light speed.
So in the future galactic commerce may be centered around access to quantum coherence bandwidth.
You could probably get a better return off trading cultural information, such as famous plays or novels. Data doesn't take up much space, so you could use a relatively small, robotic ship and get a pretty big return. Or just use a really big communications laser and hope someone is listening.
yes really, there was such a thing and here is an IRC log featuring a complete bunch of idiots and RMS. http://www.after-y2k.com/abacusworldexpo/ircRMS.html
The buyer? Well, he dresses all in white, has a big white beard, talks out of burning bushes...
An old guy dressing in white, playing with fire, and hiding in bushes, sounds more like a mentally disturbed person than the almighty Creator.
That or Moses spent a little too much time in the sun...
Slashdot Nerdiness at its best! The country is on the brink of unstoppable financial catastrophe that may make Great Depression seem mild, major banks have come || this close to failing in the last few days, the best economist on the planet has been openly panicking on his blog, but Slashdot decided to talk about the financial theory of science fiction! Maybe, just maybe, since the original story is about Krugman (who is considered by many to be the most celebrated economist of the present) you should go and check out his blog, read his posts for the last 20 days, and realize that we probably should be talking about something else now...
Human history becomes more and more a race between education and catastrophe.
H.G. Wells, "The Outline of History"
I was just reading a piece on economics which termed 1000BC to 1800AD "The Flintstones" and 1800AD to the present "The Jetsons". It's only been a relatively short time period where the economy has grown (hence *changed* in material respects) so rapidly that 50-year investment cycles are hard to fathom.
Yes, it turns out that some forms of economic activity are hard to justify as we charge toward the looming technological singularity. something which _might_ make you the big bucks in 50 years, will get Wall Street screaming for blood Isn't that interesting? We have the attention span of an ADHD mayfly for raising capital, but we're happy to sit on our liabilities for hundreds of thousands of years.
http://en.wikipedia.org/wiki/Yucca_mountain
At some scale, common abstractions break down, such as your broad-brush of "subsidy" to the whole of global food production above. Some human endeavors are larger than the greed-loop in a Wall Street tycoon, who is, after all, merely engaged in a culturally shaped manifestation of his underlying biological drives.
The solution, obviously, is genetic engineering. One must first genetically alter the human population with biological drives compatible with 50-plus year investment cycles. In 50 to 100 years, a suitably modified humanity would support any length of transgalactic investment cycle you might wish to contemplate.
If you started with some Wikipedian root stock (barely qualifying as human as it stands), you could even set things up so that people compete for the opportunity to deliver your goods for free. Just be sure to suppress the "crow" complex, or they'll bring you back a cargo container filled with shiny lumps of carbon.
Since being an interstellar delivery boy would basically mean leaving behind all your friends and loved ones (as they aged and died and you didn't) only the worst losers would be willing to take the job (unless you were going to pay them and their families a king's ransom). Your recruitment pool would basically consist of orphaned slackers, lazy out-of-work robots, one-eyed mutants, alien doctors with no discernible human skills, and grad students. How on earth could you build a delivery service with just that to choose from?
SJW: Someone who has run out of real oppression, and has to fake it.
A repressed financial theory is uncovered that can make me rich! and as I skim the article, I see that Figure II is BLANK!!!! What is missing!?! and how will I ever save for retirement on Alpha Centauri?????
Inquiring minds want to know!
I'm in my right mind and I have the answer to everything!
Haven't read this one, but every theory of how to make the world better by Paul is based on more regulation and higher taxes. As far left as one can get without owning Citgo.
Actually, that's just a travelling colony so to speak, with the added cost of being able to also bring it all back.
I mean, take the two following scenario:
1. We send a bloody huge colony ship there, and it all stays there. Then all it sends back are some smaller container ships with the ore they want to export.
2. We send a bloody huge colony ship there. But on the way back we have to carry the ore _and_ the same bloody huge colony ship, with all the people and the life support and everything.
Scenario 2 doesn't just involve hauling a lot more weight on the way back (hence bigger engines, more fuel, etc), but also hauling a bigger ship on the way there. Since, you know, it has to also have some space for the ore.
But at the very least, that way back is what really sucks. The same big colony ship which would normally be a one-way trip, now has to do the trip back too.
I also don't think it solves the problem of fluctuating prices. In fact, methinks it makes it worse. Let's look at two scenarios again. Let's say, Tau Ceti in both cases, and as I was saying, an average of half the speed of light for the whole trip, just as example values.
1. Ordering a shipment of unobtanium from a colony. You send a radio signal, it takes 12 years to get there, it takes the container ships 24 years to come here. Total: 36 years.
2. Your corporation-ship "sails" off to find unobtanium on Tau Ceti. The ship takes 24 years to get there, and another 24 years to come back. Total: 48 years.
In the second case, you now have to predict what the prices will be in 48 years from now.
And the whole point was that extrapolation of current trends sometimes doesn't cut it. You can look at the steadily increasing price for some resource over a whole century, and think "man, this thing will be worth a fortune in 48 years." Then you come back and discover that somewhere in the middle of that interval, someone discovered something that made your resource dirt cheap.
Think cloth and the introduction of the powered looms in the 19'th century. You could look at a graph of the prices throughout the 18'th century and think, "man, by 1848, the prices will be sky high. Let's buy the biggest container ships available and go bring some cloth from Tau Ceti." And you'd be wrong, because by the middle of the 19'th century, the price had dropped a lot.
Or look at Aluminium. In 1884 it was selected as the material for the capstone of the Washington Monument because it was a very expensive metal, more expensive than silver. An ounce of it cost more than a worker's daily wage. In just 2 years after that, and actually before that monument was finished, a new production process hit and caused the price of aluminium to collapse. It's just the kind of thing I'm talking about. That was a forecast for the next four years: that when the monument is finished, aluminium would still be, pretty much, a precious metal and a whole capstone made of it would be a thing that makes people go, "wow!" It only took 2 years for that to turn out wrong.
And nowadays it's a bit over a dollar per _pound_. So by the same comparison with a worker's wage, what was once worth a whole day's work, nowadays won't even hire someone for a minute. (Going by the federal minimum wage, anyway.) How's that for a price drop?
A polar bear is a cartesian bear after a coordinate transform.
"This paper, then, is a serious analysis of a ridiculous subject, which is of course the opposite of what is usual in economics"
which is normally a ridiculous analysis of a serious subject?
The funny thing is, you're not going to just transfer money at the speed of light. Sorry.
Money is just something that mediates transfers of goods, so to speak. You can buy something from Japan for dollars, only because Japan then plans to (eventually) buy something back from you and pay with those dollars.
If you can't sell as much stuff as you buy, the value of your coin drops until you reach equilibrium. It's a kind of supply and demand. And if you don't sell anything, the value of your money is exactly zero.
If I'm a colony and you're another country dealing with me, the only reason why you'd want my money (let's call them Tau Ceti Credits) is if you can buy anything with them. Otherwise you'll sell your stuff on Earth for Euros or US dollars. At least you can buy something with those.
Or if I'm paying in an Earth-based currency, without sending anything tangible, then effectively an Earth-based government is letting me print their money and inflate their economy. If I can just send you US dollars without earning those dollars by selling stuff to Earth, then effectively the US government lets me "print" (or electronically create out of nothing) an endless supply of US dollars. No matter how you want to organize it, effectively then US government pays the price for that uranium you're sending me.
They might even do it if it's an american colony, but nevertheless, it's not as much trade, it's just a government paying for uranium to be sent to their colony. And then we can even forget about the part about paying what it's worth when it arrives. Since it's the government buying uranium to send to the colony, then it can jolly well pay the price at the moment of buying it. There we go. We just bypassed the whole problem of price fluctuations and who pays interest to whom.
The moment it's a trade is when you send me some uranium, but then can spend the Tau Ceti Credits on something that my colony produces. And there you run into the same problem I was describing anyway.
I mean, sure, you know I'm buying X tons of uranium per year, you won the contract for that, you know I'll pay when it arrives. Nice. The flow in that direction is solved. But that's the trivial half of the problem. The flow in the opposite direction is still not solved, though. You're still faced with the issue of what do you buy from me with those Tau Ceti Credits. But anything your order from me now, you'll get in 36 years. How do you know what to buy from that colony? Can you predict the demand and the prices on _Earth_ in 36 years from now? That is the hard half problem.
A polar bear is a cartesian bear after a coordinate transform.
Interstellar Trade is my specialty!
To achieve speed of light is so hypothetical?
Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
Lenders make the rules. They are they only ones that matter. They only care about their own time.
I don't care what you do with the goods or how much you age in the time I age. If I loan you money, all I care about is that the payments are in my bank account regularly according to my time.
A slashdotter who didn't build his own computer is like a Jedi who didn't build his own lightsaber.
Asimov's idea of agriculture worlds feeding Trantor or however it was spelled, the city-world Coruscant ripped off, that always struck me as absurd. Look at how expensive space flight is, look at the distance, and we're to expect the world imports its food? Preposterous! But then again, what's the cost of space travel? In Asimov's setting, it was as relatively cheap as ocean transport today. We eat food produced halfway around the world. In the not so distant past, only the rich could afford the extravagance of that kind of luxury since transportation cost so much.
So much of a scifi setting will depend on the nature of technology. In a realistic space setting, i.e. no FTL drives, I don't even really see how commerce would be viable. We're going to see how the technology singularity hits us for the first time here, who the fuck knows what the consequences of that will be. Tech is moving at such a clip, it keeps outdating our image of the future. The original scifi spaceships were like steamships, later they looked like WWII submarines on the inside, later still we're coming up with starfighters flown on manual with computers that take up rooms. I think Ian M. Banks probably got it the closest to right about what true starships would be like, controlled by AI's dwarfing all human understanding, humans along for the ride but in no way necessary for the operation of the ship.
I think for any reasonable scifi setting, interstellar trade would mostly be luxuries and manufactured goods that cannot be replicated domestically. Basic foodstuffs would not be worth the effort of transporting, rare wines would be. Nobody would need a basic hoverbike manufactured three light years away but maybe the secret of constructing AI matrices is a closely guarded guild secret and so they need to be shipped in at great expense.
If you have a universe like Star Wars where the entire galaxy can be crossed on hyperdrive in an hour, you could probably run a fucking interplanetary pizza delivery service. It all depends on the way the tech is presented.
Kwisatz Haderach
Sell the spice to CHOAM
This Mahdi took Shaddam's Throne
Perhaps the only goods worth trading over such distances will be information. Science, news, literature, etc.
Is that a ding I hear? GET BACK IN THE MAGIC HOUSE!!!
Or whatever. It takes a metric buttload of energy to get anything of reasonable mass anywhere near the speed of light. That energy has value. Anything that is sent from one star system to another has to be really lucrative to get there, because it's gotta be worth, at a bare minimum, more than the cost of the energy to propel and decelerate it, with interest.
If you're thinking about sending uranium somewhere as a power metal, think again. You can't use all the energy in uranium to get it anywhere near lightspeed. Food in general is a bust, since it'll be cheaper to manufacture some sort of energy-intensive agriculture anywhere than to accelerate food to a high enough speed to matter.
And, of course, if energy is dirt cheap, there will be no market for uranium for power, and everybody will be able to manufacture pretty much what they like (there are few manufacturing problems that can't be solved with enough energy). Anything worth shipping over interstellar distances is going to be really rare and/or intrinsically valuable. It's conceivable that accelerating the Mona Lisa to lightspeed is worthwhile; accelerating gold will never be.
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
Spaceships might be helpful in transporting people, robots, factories, colony modules, raw materials or solar collector satellites throughout a solar system, but interstellar distances are so vast that transportation cost quickly overrun any trade of something with mass. Information on the other hand only costs as much as a good, clear signal (likely with an Earth-based broadcast, a Earth orbiting relay satellite, and a Pluto orbiting relay satellite). Plus information can travel at the speed of light and can be encrypted to prevent easy theft. Information could include scientific data and discoveries, works of art, biological organisms and compounds (via DNA sequences), as well as technological know-how.
Spaceships might be necessary to initiate digital trade with alien civilizations or to rekindle economic ties with rogue human colonies, but if a solar system does not have the natural resources to build advanced technology then why would anyone settle there?
Extrasolar human colonization will likely be motivated by curiosity, courage, and the desire to spread human civilization - not by economics. Any shipments to established colonies likely won't be motivated by money but rather by sympathy. The hope that said colony may survive. Sure there may be economic benefits for having extrasolar colonies, but it is unlikely that they will justify the costs.
The sad truth is that interstellar economies using spaceships will never happen unless someone figures out hyperdrives or instant wormholes or something of the sort.