How will sleeper ships travels be funded?

[ray245]

Sleeper ships are probably the main means of space travel if there is no real workaround to build any sort of FTL ships. The problem is, who is willing to fund such an endeavor? The cost of building the ship and to keep it running for several centuries would be rather astronomical even for the wealthy. Their wealth would have to last them for several hundred years when they are being kept in stasis.

So is there any realistic means which would actually incentivize human civilisation to fund such travels?

[Broomstick]

Even more than the problem of funding - we don't have any sort of "sleeper" technology.

[ray245]

Even more than the problem of funding - we don't have any sort of "sleeper" technology.

I know. This is just some purely theoretical idea. The problem with many of those theoretical ideas is people often neglect to think about how those technology will be funded.

[Simon_Jester]

The most likely solutions I can think of would involve either a government, or a private organization pooling the resources of many, many people to produce very large trust funds.

Assuming these are ever things that it's physically possible to build, of course.

[Alferd Packer]

What immediately comes to mind as a cost-saving measure over a traditional sci-fi sleeper ship is some kind of mind-upload/android body setup. Get rid of the organic bodies, and the barrier to entry becomes much lower and the ships more economical to crew. Hell, if the mind upload is a copy (rather than requiring destruction of the original brain), you can crew your ship without any risk to the original beings.

Of course, all that presupposes that mind uploading and sentient AI is possible, but if it is, it would offer clear benefits over trying to maintain fragile organic bodies in hibernation for a period of decades or centuries.

[GrandMasterTerwynn]

Even more than the problem of funding - we don't have any sort of "sleeper" technology.

I know. This is just some purely theoretical idea. The problem with many of those theoretical ideas is people often neglect to think about how those technology will be funded.

Actually, we could probably "suspend" people just fine (hypothermia them to death, and then carefully freeze the resulting corpse using the magic of chemistry to prevent the formation of cell-wrecking ice crystals.) The problem lies in un-suspending them (also, can one really call it a "sleeper" ship, when everyone aboard is, technically, dead?)

So, setting that aside ... what are the costs of building a slow starship? The structure itself wouldn't be tremendously expensive ... you just have to hollow out a comet or asteroid of the appropriate size. If your civilization has reached the point where it would seriously consider building starships, hollowing out asteroids ought to be old-hat; since you would be doing that in the process of mining them for resources, or repurposing them for space colonies. The first major expense is the R&D for the automation systems (which will have to be perfectly reliable for centuries, but the research into this would be useful inside the confines of the solar system,) and the propulsion system (a starship propulsion system will have a power output that will absolutely dwarf anything useful inside a solar system ... meaning that production numbers will be very low indeed.)

The biggest expense is manufacturing the antimatter you'll need for the rocket (while a pure M/AM rocket is out in the realms of fantasy wizard-land in a scenario like this, an antimatter-catalyzed fission or fusion rocket would substantially cut down on the mass proportion you'd have to spend on fuel.) It's expensive because you have to build a whole bunch of particle accelerations to create antimatter by smashing little bits of ordinary matter together at really high speeds.

So ... pretty substantial infrastructure investment. Because of antimatter's exceptionally high weapons potential, manufacturing the quantities needed to launch a slow starship is going to require the consent of numerous governments. All of which are going to want a say in who gets seat aboard the starship, what contractors are responsible for what pieces, etc, etc, etc.

Basically, a "sleeper ship" would be a multinational effort spread out across much of the solar system.

To get it down to an effort that could be funded by a single country, or a sufficiently large corporation, you would have to reduce the mass that you're trying to lob between stars. As Alferd Packer suggests, you can eliminate quite a bit of mass by eliminating the people. With some sort of mind-upload machinery, you could conceivably encapsulate a person's experiences onto something much smaller and lighter than the 1500 or so ccs of jello that it's stored in now. Send along some sort of future 3D printing machine to make the cybernetic bodies at the other end, and a bank of cryoically preserved embryos; and you could probably fit all of that onto a fusion rocket not needing any antimatter at all.

It's still going to be a multi-government project, though. There's no shareholder value in lobbing several hundred billion dollars (you're probably not going to manufacture enough of them to recoup your research and development costs) worth of starship off into the galactic wilds, never to be heard from again. (Unless what you were sending was a construction crew that was going to build a giant laser receiver and body printer for people to have their mind uploads beamed to beautiful Proxima Centauri b; at which point, you could charge would-be travelers a toll to use the beaming station. However, given the decades or centuries you'd have to wait before charging the first tolls; the initial endeavor would still end up being government-funded.)

[Broomstick]

What immediately comes to mind as a cost-saving measure over a traditional sci-fi sleeper ship is some kind of mind-upload/android body setup. Get rid of the organic bodies, and the barrier to entry becomes much lower and the ships more economical to crew.

With apologies to all the would-be transhumanists waiting for the Singularity, I think it more likely we'll get suspended animation before brain uploading. There are at least natural models for such "hibernation", there are none for uploading,

[SpottedKitty]

The most likely solutions I can think of would involve either a government, or a private organization pooling the resources of many, many people to produce very large trust funds.

Isn't this how it was done in the early Diaspora period of the Honor Harrington stories? E.g. the Manticore expedition took hundreds of years to reach its destination, with background support from an organisation back on Earth funded by the colonists.

[Solauren]

It really gets down to a question of economy.

How advanced along is the society in question, and how cheap is the needed technology?
I mean, if you get to the point where it costs $1000 to put someone into a sleeper chamber, and $2000 to wake them up, hell, that's cheaper then a new car is today.

It will probably start off as a big, multi-national/corporate project, but as the technology matures and becomes cheaper, and the infrastructure improves, the price will drop.

Supporting it wouldn't be hard either. Keep the crew itself in suspended animation until needed.

This was ALMOST the plot line of the movie Passengers (saw it over the weekend). Sleeper ships where in use, hordes of automation, and the idea of any of the tech failing was unthinkable.

[Simon_Jester]

Just for clarification, that's the setting of the movie Passengers. The plot is what happens when something interestingly different happens.

[FaxModem1]

It's also worth noting that in Passengers, lower class customers have it that in exchange for cheaper tickets, the company transporting them gets 20 percent of their income until the day they die on the colony world, as well as a lifelong contract working for the company.

Essentially, you cut costs by establishing interstellar company towns for resources and trade on the planet that ships these things back to Earth. A futuristic version of indentured servants, and a nice way of keeping the money coming in.

[GrandMasterTerwynn]

It really gets down to a question of economy.

How advanced along is the society in question, and how cheap is the needed technology?
I mean, if you get to the point where it costs $1000 to put someone into a sleeper chamber, and $2000 to wake them up, hell, that's cheaper then a new car is today.

The cost of putting the traveler aboard the ship is a tiny, tiny, tiny fraction of the cost of getting them to their destination. To freeze a person, you're talking about moving a couple of megajoules worth of of energy around. Moving them at 10% of the speed of light to their destination, requires an energy investment of roughly 900,000 gigajoules per kilogram of mass. Note that this doesn't take thermal efficiency into account. Not to mention each passenger is not only paying to get their assorted kilograms to their destination, but they're also paying to get the assorted kilograms of the ship to its destination, and the cost of hauling all that fuel.

So, yes, the "new car" might get cheaper, but it's still going to cost a trillion dollars to fill the gas tank.

It's also worth noting that in Passengers, lower class customers have it that in exchange for cheaper tickets, the company transporting them gets 20 percent of their income until the day they die on the colony world, as well as a lifelong contract working for the company.

I initially thought of that too, but decided it would've just been an example of a failure to do the math. Also, given that these are sleeper ships, there'd be little to stop the indentured servants from staging a violent revolt at their destination to get out of their contracts. Not to mention, what the fuck is so valuable that it'd be worth spending a century shipping it back to Earth?

[FaxModem1]

It's also worth noting that in Passengers, lower class customers have it that in exchange for cheaper tickets, the company transporting them gets 20 percent of their income until the day they die on the colony world, as well as a lifelong contract working for the company.

I initially thought of that too, but decided it would've just been an example of a failure to do the math. Also, given that these are sleeper ships, there'd be little to stop the indentured servants from staging a violent revolt at their destination to get out of their contracts. Not to mention, what the fuck is so valuable that it'd be worth spending a century shipping it back to Earth?

It really depends on what the first colony's colonists were composed of. If they were all utter company/national loyalists, they might have set the tone for how incoming colonists are expected to behave.

It's also worth noting in Passengers that passengers of the Avalon aren't the first to arrive at the colony, but one of many going to settle that planet. Their destination is also considered the 'perk assignment' for colonists. We also see that each colonist is interviewed, and has a social profile that the rest of the ship's manifest can view. Chris Pratt's character, Jim, also only got on the ship's manifest and a discount due to his engineering skills. Unless the company was infiltrated, the colonists would probably be screened for only compliant colonists. The other passenger we get to know, Aurora(Jennifer Lawrence's character), is presented as a rather rich person who could easily afford the ticket as she wanted the adventure.

It's also worth noting that in the movie, Earth is supposedly rather overpopulated, so there is high demand for passage. If there's a guarantee of continued purchases and customers, no matter the price, you can get away with a lot when it comes to price. I wouldn't be surprised if people threw their life savings to get a ticket.

EDIT: Forgot to add, it also depends on how many ships go back and forth between Point A and B. If it's only one making the century long journey, you have quite a wait, but if it's a dozen or so, you can expect new colonists and/or goods every dozen or so years.

[ray245]

It's also worth noting that in Passengers, lower class customers have it that in exchange for cheaper tickets, the company transporting them gets 20 percent of their income until the day they die on the colony world, as well as a lifelong contract working for the company.

I initially thought of that too, but decided it would've just been an example of a failure to do the math. Also, given that these are sleeper ships, there'd be little to stop the indentured servants from staging a violent revolt at their destination to get out of their contracts. Not to mention, what the fuck is so valuable that it'd be worth spending a century shipping it back to Earth?

It really depends on what the first colony's colonists were composed of. If they were all utter company/national loyalists, they might have set the tone for how incoming colonists are expected to behave.

It's also worth noting in Passengers that passengers of the Avalon aren't the first to arrive at the colony, but one of many going to settle that planet. Their destination is also considered the 'perk assignment' for colonists. We also see that each colonist is interviewed, and has a social profile that the rest of the ship's manifest can view. Chris Pratt's character, Jim, also only got on the ship's manifest and a discount due to his engineering skills. Unless the company was infiltrated, the colonists would probably be screened for only compliant colonists. The other passenger we get to know, Aurora(Jennifer Lawrence's character), is presented as a rather rich person who could easily afford the ticket as she wanted the adventure.

It's also worth noting that in the movie, Earth is supposedly rather overpopulated, so there is high demand for passage. If there's a guarantee of continued purchases and customers, no matter the price, you can get away with a lot when it comes to price. I wouldn't be surprised if people threw their life savings to get a ticket.

EDIT: Forgot to add, it also depends on how many ships go back and forth between Point A and B. If it's only one making the century long journey, you have quite a wait, but if it's a dozen or so, you can expect new colonists and/or goods every dozen or so years.

My point is, no matter how rich you are, you aren't going to be rich enough to pay for a spot yourselves. The ship is going to travel for hundreds of years while you are asleep. In the meantime, there will be technological advances, inflations and etc that makes you worth less the longer time passes.

Think about it. You're spending hundreds of years doing absolutely nothing productive. Even if you are rich enough, there is very little odds that you are rich enough to maintain the same status of wealth for centuries. At the same time, which company wants to be responsible for centuries worth of maintaince, quality control and insurance?

Our current financial models are utterly horrible at incentivising people towards any long term goals. Who wants to invest in stuff that has no return of investment value for hundreds of years?

[Zixinus]

In order to answer OP's qustion, first a simpler question has to be answered: why are you sending slow-ships to other star systems?

If its a colony of some nation-like entity that seeks expansion, it has to be one with the funds and infrastructure to do it. They also would have to be one that seriously can plan long-term enough for the venture on another solar system to pay off. It also has to be stable enough to make viable long-term plans.

There is Avatar's excuse, which is about magic materials that are worth crossing the interstellar space for. Then, it's the value of that material holding the venture up, even through the years.

Often there is a pressing reason, the slow-ship is actually an escape from either some natural disaster (to use a dramatc example, the sun blowing up) or hostile aliens. This was actually the plot of an old game that featured this, Alien Legacy.
The excuse of "Earth is too polluted and uninhabitable" often comes up too. But if you have this kind of tech and the tech required to adapt to an alien planet, don't you have the tech to make Earth habitable again?

A more rare reason is simple science exploration, where you need to send people to do the job (maybe even have a compelling curiosity like a planet with life or aliens or something else). In some cases there are new colonies simply because its more economical that way and the tech for self-sufficiency is that good (which would make sense if you are using slow-ships to begin with).

A common excuse is overpopulation which doesn't make that much sense to me. The problem is that the sheer energy required to send and receive people. It's like trying to save a full cruise ship's crew with one rowboat to a distant island. Even if you could carry hundreds of thousands, that is still a relatively small number of people in terms of population just today.
For the cost of a slow-ship, you could make them a space habitat or expand already available living spaces.

My point is, no matter how rich you are, you aren't going to be rich enough to pay for a spot yourselves. The ship is going to travel for hundreds of years while you are asleep. In the meantime, there will be technological advances, inflations and etc that makes you worth less the longer time passes.

Unless you hand over your entire or most of your fortune now. You won't be paying when you get there, but you're paying just to get aboard.

[Simon_Jester]

The most probable way to make this work financially involves, again, either having a government do it (because governments can continue to exist for that long) or forming a corporate trust fund to invest the money and provide continuous payouts.

The idea of financial instruments that (theoretically) last forever and pay out forever is not a new one; it's been around for centuries. There are banks and firms that have existed continuously for around 200-300 years, and there have been financial instruments that lasted for something like that span of time. The main reason financial instruments older than that don't exist is that they hadn't been invented yet- finance as we know it did not exist.

It's also worth noting that in Passengers, lower class customers have it that in exchange for cheaper tickets, the company transporting them gets 20 percent of their income until the day they die on the colony world, as well as a lifelong contract working for the company.

I initially thought of that too, but decided it would've just been an example of a failure to do the math. Also, given that these are sleeper ships, there'd be little to stop the indentured servants from staging a violent revolt at their destination to get out of their contracts. Not to mention, what the fuck is so valuable that it'd be worth spending a century shipping it back to Earth?

For this to work there are two assumptions necessary.

One condition is simple. There has to be some way to enforce compliance on the indentured workers. Not only does shipping them to other star systems have to seem cheap enough to be worth doing, but there has to be a way to make them work off the cost of the passage. However, it isn't much of a stretch to assume that a company which has started hiring indentured servants and shipping them to other stars will have already figured out a solution to this problem. Many solutions can be imagined, although in theory most of them could be subverted by a well-run laborers' revolt, that doesn't mean they are inconceivable or can't possibly work.

The other condition that has to be met is more interesting. Namely, the cost of powering a starship has dropped to something manageable. We can imagine, say, a society in which the solar system has a hundred billion people and enough solar power satellites to make a fair start on a Dyson swarm. In such a future, the idea of investing umpty gigajoules to transport a human being to another star system may not seem so daunting.

Today, the cost of a gigajoule of energy in a conveniently stored, easily liberated, mechanically useful form... well, gasoline liberates 46 MJ/kg, so one gigajoule translates as 21.7 kg of gasoline, or 30.5 liters, or around seven gallons for Americans in the audience. The price is going to be some double digit number of dollars.

The price of a comparable amount of electrical energy... Well, one kilowatt-hour is 3.6 megajoules of electricity, so a gigajoule is 278 kilowatt-hours, and at typical electrical power costs that works out to, again, some double digit number of dollars.

But a thousand years ago, the cost of a gigajoule of energy was a lot higher. Because that energy was available only in the form of muscle power. Providing a gigajoule of musclepower requires you to feed animals or people- either to feed many of them for a short time, or a few of them for a very long time. Either way, it's going to cost (in relative terms) much more than a double digit number of dollars.

For example, a rough physics calculation indicates that lifting all the stones required to build the Great Pyramid took roughly 300 gigajoules of energy, because that is the approximate gravitational potential energy of the stones in the pyramid.

[Note that this is not even attempting to work out the energy required to move the stones from their quarries, just the effort to lift them all into place- the gravitational potential energy that had to be 'stored' to raise that many rocks that far off the ground. So this is solely judging the part of the job after stones have been delivered, but before they're positioned on top of the assembling pyramid]

To power cranes capable of providing this energy in the present day, assuming 10% efficiency... This would take, based on the figure of "between 10 and 100 dollars per gigajoule," take between 30 and 300 thousand dollars to pay for the gasoline or electricity to power the cranes. Now, obviously there would be many, many other expenses involved in building a new Great Pyramid, and total construction costs would be many millions. But that specific cost, of just lifting the stones, would not be very daunting today- it costs as much as, say, a house.

By contrast, the physical labor required to raise all the stones into position at the historical Great Pyramid would have seemed much more daunting to ancient or medieval viewers. Even if the stones had magically appeared on the ground around the construction site, ready to be lifted into position, getting them up into place would cost A LOT more than even a large house.

[This is ignoring all the other costs that would go into building the pyramid- because we're looking only at the energy cost, the part that involves measurable numbers of gigajoules of energy expended to push something into position. Just as you are thinking only in terms of the energy cost to push the starship up to speed and decelerate it at its destination]

The conclusion here is, simply, that it may be that in the distant future, energy becomes orders of magnitude cheaper than it is today. Thus, the task of powering a starship may not in and of itself be massively expensive, even if it seems so expensive today. Just as the task of lifting three million tons of building stone into a pyramid is not in and of itself massively expensive today. Even though it was so expensive, 3000 years ago.

[GrandMasterTerwynn]

The other condition that has to be met is more interesting. Namely, the cost of powering a starship has dropped to something manageable. We can imagine, say, a society in which the solar system has a hundred billion people and enough solar power satellites to make a fair start on a Dyson swarm. In such a future, the idea of investing umpty gigajoules to transport a human being to another star system may not seem so daunting.

An even more interesting question is what sort of social system could arise that would allow a human population in excess of a hundred billion people, with the resources necessary to disassemble enough asteroids (or planets ... Mercury isn't really doing anything useful right now, is it?) to build the solar power collection real-estate needed to make petajoule-level energy expenditures reasonably trivial. It's difficult to envision a society centered around our present model of laissez-faire capitalism not killing itself before reaching that point. It's incredibly difficult to imagine modern humans and their profound temporal myopia making it that far.

Today, the cost of a gigajoule of energy in a conveniently stored, easily liberated, mechanically useful form... well, gasoline liberates 46 MJ/kg, so one gigajoule translates as 21.7 kg of gasoline, or 30.5 liters, or around seven gallons for Americans in the audience. The price is going to be some double digit number of dollars.

The price of a comparable amount of electrical energy... Well, one kilowatt-hour is 3.6 megajoules of electricity, so a gigajoule is 278 kilowatt-hours, and at typical electrical power costs that works out to, again, some double digit number of dollars.

Assuming an electrical generation rate of $0.08/KWh, the cost of a gigajoule of energy is $22.24. To accelerate a kilogram of mass to 10% of c, and stop it at the other end works out to be $20 million dollars. Or about $1.5 billion to send a whole person ... and roughly sixteen cents to remove enough thermal energy from them to put them into cryonic suspension and put it all back on the other end.

But a thousand years ago, the cost of a gigajoule of energy was a lot higher. Because that energy was available only in the form of muscle power. Providing a gigajoule of musclepower requires you to feed animals or people- either to feed many of them for a short time, or a few of them for a very long time. Either way, it's going to cost (in relative terms) much more than a double digit number of dollars.

For example, a rough physics calculation indicates that lifting all the stones required to build the Great Pyramid took roughly 300 gigajoules of energy, because that is the approximate gravitational potential energy of the stones in the pyramid.

[Note that this is not even attempting to work out the energy required to move the stones from their quarries, just the effort to lift them all into place- the gravitational potential energy that had to be 'stored' to raise that many rocks that far off the ground. So this is solely judging the part of the job after stones have been delivered, but before they're positioned on top of the assembling pyramid]

To power cranes capable of providing this energy in the present day, assuming 10% efficiency... This would take, based on the figure of "between 10 and 100 dollars per gigajoule," take between 30 and 300 thousand dollars to pay for the gasoline or electricity to power the cranes. Now, obviously there would be many, many other expenses involved in building a new Great Pyramid, and total construction costs would be many millions. But that specific cost, of just lifting the stones, would not be very daunting today- it costs as much as, say, a house.

According to Herodotus, the Great Pyramid took 20 years to build, and required a labor force of 100,000. Since it was all constructed via manual labor, we can get an extremely rough estimate of how much it would cost to build. If we say that the laborers were all paid the average American construction worker's salary of $35,750 per year (and the ruins of the huge city built to house the Pyramid's laborers suggest that they would've been the ancient Egyptian equivalent of middle class,) then the Great Pyramid would end up costing something like $71.5 billion dollars worth of energy expenditure.

And that was to move something like 5.3 billion kilograms of rock around. Since the Great Pyramid is an enormous pile of rocks, we can gain a rough estimate of how much it would cost today by looking at the Hoover Dam, which is an enormous pile of carefully engineered concrete (basically rock) that masses about 8 billion kilograms. Its construction cost, in modern dollars, is $750 million.

So between the time of the ancient Egyptians, and today, we've improved the cost of usefully-directed energy by two orders of magnitude.

An improvement of two orders of magnitude would bring the cost of shipping a person over interstellar distances at 10% c down to $150 million. That's not bad ... it's a bit over double the price NASA is currently paying per seat to have the Russians fly astronauts to the ISS. To get the cost down to the point where the scenario in Passengers makes sense, one would have to find a further two or three orders of magnitude of improvement in the cost of energy (going by the numbers, if we assume an engineer with a $100K salary has a fifty year useful working lifespan, they're borrowing a million dollars for their ticket.)

Here is an interesting observation: Four orders of magnitude worth of improvement in the cost of energy would mean that $0.08 would buy an entire year's worth of electrical energy for the average American household. For the average person, this would probably mean they're in a post-scarcity economy ... well, for everything but tickets on starships, at least.

[FaxModem1]

There's actually a line in Passengers about that. Jim is being interviewed by Aurora about why he left Earth.

His main reasoning is that, as a mechanically minded and rather skilled person, he can fix things on a colony world and make a difference, as opposed to Earth, where if something malfunctions or breaks, they just get a new one. I'm not sure how much of that is hyperbole, but it does give us a perspective on their way of life there.

[Simon_Jester]

According to Herodotus, the Great Pyramid took 20 years to build, and required a labor force of 100,000. Since it was all constructed via manual labor, we can get an extremely rough estimate of how much it would cost to build. If we say that the laborers were all paid the average American construction worker's salary of $35,750 per year (and the ruins of the huge city built to house the Pyramid's laborers suggest that they would've been the ancient Egyptian equivalent of middle class,) then the Great Pyramid would end up costing something like $71.5 billion dollars worth of energy expenditure.

And that was to move something like 5.3 billion kilograms of rock around. Since the Great Pyramid is an enormous pile of rocks, we can gain a rough estimate of how much it would cost today by looking at the Hoover Dam, which is an enormous pile of carefully engineered concrete (basically rock) that masses about 8 billion kilograms. Its construction cost, in modern dollars, is $750 million.

So between the time of the ancient Egyptians, and today, we've improved the cost of usefully-directed energy by two orders of magnitude.

The differences in construction techniques involved raise some issues- for example, Hoover Dam was built in the middle of a desolate wilderness hundreds of miles from any developed area. Extensive blasting had to be done to create the place the dam was constructed in. Pieces of precision machinery had to be made and installed. But your analysis isn't unreasonable. At most, I might say the difference is three orders of magnitude rather than two.

An improvement of two orders of magnitude would bring the cost of shipping a person over interstellar distances at 10% c down to $150 million. That's not bad ... it's a bit over double the price NASA is currently paying per seat to have the Russians fly astronauts to the ISS. To get the cost down to the point where the scenario in Passengers makes sense, one would have to find a further two or three orders of magnitude of improvement in the cost of energy (going by the numbers, if we assume an engineer with a $100K salary has a fifty year useful working lifespan, they're borrowing a million dollars for their ticket.)

Here is an interesting observation: Four orders of magnitude worth of improvement in the cost of energy would mean that $0.08 would buy an entire year's worth of electrical energy for the average American household. For the average person, this would probably mean they're in a post-scarcity economy ... well, for everything but tickets on starships, at least.

Basically agreed- but you see what I'm getting at here.

It is within the realm of the plausible to imagine that a future society may make enough technological progress that they can actually shuffle the amounts of energy involved in launching starships, until the real cost of the ship has more to do with the skilled labor that designs and operates it. Just as the real cost of most modern construction projects is the labor involved, and not because the laborers are using their muscles to supply the energy required to move stuff around.

[ray245]

The most probable way to make this work financially involves, again, either having a government do it (because governments can continue to exist for that long) or forming a corporate trust fund to invest the money and provide continuous payouts.

The idea of financial instruments that (theoretically) last forever and pay out forever is not a new one; it's been around for centuries. There are banks and firms that have existed continuously for around 200-300 years, and there have been financial instruments that lasted for something like that span of time. The main reason financial instruments older than that don't exist is that they hadn't been invented yet- finance as we know it did not exist.

It's also worth noting that in Passengers, lower class customers have it that in exchange for cheaper tickets, the company transporting them gets 20 percent of their income until the day they die on the colony world, as well as a lifelong contract working for the company.

I initially thought of that too, but decided it would've just been an example of a failure to do the math. Also, given that these are sleeper ships, there'd be little to stop the indentured servants from staging a violent revolt at their destination to get out of their contracts. Not to mention, what the fuck is so valuable that it'd be worth spending a century shipping it back to Earth?

For this to work there are two assumptions necessary.

One condition is simple. There has to be some way to enforce compliance on the indentured workers. Not only does shipping them to other star systems have to seem cheap enough to be worth doing, but there has to be a way to make them work off the cost of the passage. However, it isn't much of a stretch to assume that a company which has started hiring indentured servants and shipping them to other stars will have already figured out a solution to this problem. Many solutions can be imagined, although in theory most of them could be subverted by a well-run laborers' revolt, that doesn't mean they are inconceivable or can't possibly work.

The other condition that has to be met is more interesting. Namely, the cost of powering a starship has dropped to something manageable. We can imagine, say, a society in which the solar system has a hundred billion people and enough solar power satellites to make a fair start on a Dyson swarm. In such a future, the idea of investing umpty gigajoules to transport a human being to another star system may not seem so daunting.

Today, the cost of a gigajoule of energy in a conveniently stored, easily liberated, mechanically useful form... well, gasoline liberates 46 MJ/kg, so one gigajoule translates as 21.7 kg of gasoline, or 30.5 liters, or around seven gallons for Americans in the audience. The price is going to be some double digit number of dollars.

The price of a comparable amount of electrical energy... Well, one kilowatt-hour is 3.6 megajoules of electricity, so a gigajoule is 278 kilowatt-hours, and at typical electrical power costs that works out to, again, some double digit number of dollars.

But a thousand years ago, the cost of a gigajoule of energy was a lot higher. Because that energy was available only in the form of muscle power. Providing a gigajoule of musclepower requires you to feed animals or people- either to feed many of them for a short time, or a few of them for a very long time. Either way, it's going to cost (in relative terms) much more than a double digit number of dollars.

For example, a rough physics calculation indicates that lifting all the stones required to build the Great Pyramid took roughly 300 gigajoules of energy, because that is the approximate gravitational potential energy of the stones in the pyramid.

[Note that this is not even attempting to work out the energy required to move the stones from their quarries, just the effort to lift them all into place- the gravitational potential energy that had to be 'stored' to raise that many rocks that far off the ground. So this is solely judging the part of the job after stones have been delivered, but before they're positioned on top of the assembling pyramid]

To power cranes capable of providing this energy in the present day, assuming 10% efficiency... This would take, based on the figure of "between 10 and 100 dollars per gigajoule," take between 30 and 300 thousand dollars to pay for the gasoline or electricity to power the cranes. Now, obviously there would be many, many other expenses involved in building a new Great Pyramid, and total construction costs would be many millions. But that specific cost, of just lifting the stones, would not be very daunting today- it costs as much as, say, a house.

By contrast, the physical labor required to raise all the stones into position at the historical Great Pyramid would have seemed much more daunting to ancient or medieval viewers. Even if the stones had magically appeared on the ground around the construction site, ready to be lifted into position, getting them up into place would cost A LOT more than even a large house.

[This is ignoring all the other costs that would go into building the pyramid- because we're looking only at the energy cost, the part that involves measurable numbers of gigajoules of energy expended to push something into position. Just as you are thinking only in terms of the energy cost to push the starship up to speed and decelerate it at its destination]

The conclusion here is, simply, that it may be that in the distant future, energy becomes orders of magnitude cheaper than it is today. Thus, the task of powering a starship may not in and of itself be massively expensive, even if it seems so expensive today. Just as the task of lifting three million tons of building stone into a pyramid is not in and of itself massively expensive today. Even though it was so expensive, 3000 years ago.

Even if you solved, the energy problem you still haven't solved the financial problems. Sure, the energy to transport the ship is cheap, but what about the cost of maintaining the ship over centuries? That is going to drive the cost up. There's also the issue of insurance. One would expect that the company needs to ensure the safety of the ship for centuries and to avoid being sued to bankruptcy by the passengers' family in case of failure.

This would make the challenge of keeping the ship running business profitable a daunting challenge. Not to mention the actual worth of the ship is going to degenerate because technoloigcal advances would render the ship extremely outdated by the time they reached their destination.

[Simon_Jester]

These are not insurmountable problems, they just require an organization that can invest money prudently and pay any necessary expenses out of the profits of the investment. And that is willing to do so, decade after decade, which is the only part of this that's actually difficult.

Assuming the will to do this is present, and the starting funds are sufficient, actually doing it isn't that hard. There is an entire sector of the economy that basically consists of ways to stash a pile of money so that it will grow at a steady pace over time. It would not take that much modification to turn this into a system for taking a pile of money amassed to support starship operations, and keep it around over time so that money will still be available fifty or a hundred years in the future.

Frankly, the energy problems are going to be more challenging than the financial problems. The only difference is that the consequence of failing to solve the energy problems is "no starships," whereas the consequence of failing to solve the financial problems is "starships, but the logistics falls apart and everything goes wrong."

By dwelling on the second category of problem, you're overestimating the significance of the financial side of the issue.

[GrandMasterTerwynn]

Even if you solved, the energy problem you still haven't solved the financial problems. Sure, the energy to transport the ship is cheap, but what about the cost of maintaining the ship over centuries? That is going to drive the cost up. There's also the issue of insurance. One would expect that the company needs to ensure the safety of the ship for centuries and to avoid being sued to bankruptcy by the passengers' family in case of failure.

This would make the challenge of keeping the ship running business profitable a daunting challenge. Not to mention the actual worth of the ship is going to degenerate because technoloigcal advances would render the ship extremely outdated by the time they reached their destination.

It's likely that a future society would make energy the currency of choice. Everything a person does to survive requires energy ... you need to supply power to the chemical manufacturing plants making the fertilizer for the plants that are grown for food. You need to power the irrigation systems, the harvesting and processing equipment, the factories that turn the raw foodstuffs into packaged foods, the vehicles to get the products to market, the lighting and air conditioning in the market, and the home-maker's cooking appliances.

In a society not constrained by material limits (like, for example, an economy with the resources of a solar system to tap into,) one can easily envision an economy arising on the trade of energy credits. Although if you're also not constrained by energy limits (like, for example, if you've disassembled the planet Mercury and turned it all into solar power collectors,) I'm trying to envision what sort of economy would arise from a situation like that ... maybe one based on individual creativity?

Anyway ...

What costs would there be in maintaining the ship for centuries? There are no salaries to pay, since it'll all be automated. Basically what you're spending to maintain the ship is the wattage from the ship's powerplant needed to power the repair bots. And what would an insurance company insure? There won't be any space pirates to pay ransom to. And what would a person's great, great, great grandson/daughter/niece/nephew care if great-great-great grandpa took an irreparable cosmic-ray strike to the brain en-route to Zeta Reticuli, or the ship was converted into a cloud of relativistic plasma by a rogue comet? Sure, they might assert that if aforementioned long-dead relative hadn't gone on the trip, they could've passed on an enormous sum of money thanks to the magic of compound interest ... but I'm sure an agency building a sleeper ship would have a carefully-worded legal contract that asserts that the passengers' descendants cannot make claims against the agency in the event of "acts of God;" or else, part of the price of a ticket will be to pay into a trust fund that will pay out to the passenger's descendants in the event that the ship fails due to demonstrable manufacturer's negligence (good luck proving that, though ... if the ship disappears in interstellar space, barring a failure visible by large telescope, that ship is effectively gone forever.) As for the pace of technological advance quickly rendering the ships obsolete ... barring revolutionary new physics, a civilization capable of worrying about sleeper ships may well have exhausted all avenues of technological advance by the time they get around to building such ships. Also, unless the destination is as developed as the solar system, you'd might as well transform the sleeper ship into an orbital colony once you arrive at your destination (since you'll need to refuel it before it can return home, and as has been established earlier ... it's going to need an absolute fuckton of fuel) ... the ship won't be going home again, so who cares if it's a few generations back from the modern state-of-the-art?

The very first ones will probably be built by huge multi-government cooperatives that won't care so much about profit. The passengers will go aboard with the understanding that they'll likely die before arrival, or get eaten by xenomorphs upon landing. By the time the technology gets cheap enough that people poorer than Donald Trump can afford the price of a ticket, most of the profit will be made from manufacturing the ship and selling spaces ... once the ship launches, the only way it'll cost the company anything is if it visibly blows up en-route, and that failure was obviously the result of some negligence on the part of the contactors who built it (for example, if the flight abruptly ends in a flash of 511 keV gamma rays, that would be fairly damning evidence that it lost antimatter containment.)

[Sea Skimmer]

I highly doubt you will turn a profit from filling it up with people. Earth would need to be doomed already. People who are rich won't want to throw away the value of all their wealth by going somewhere else that has nothing to buy.

Automation costs lots of money up front would tend to be the problem. If you want to go centuries though you'd almost certainly need an onboard repair capability. Stuff like debris shields would be very hard to trust over that kind of time frame, along with any electronics that operate hotter then ice.

[ray245]

I highly doubt you will turn a profit from filling it up with people. Earth would need to be doomed already. People who are rich won't want to throw away the value of all their wealth by going somewhere else that has nothing to buy.

Automation costs lots of money up front would tend to be the problem. If you want to go centuries though you'd almost certainly need an onboard repair capability. Stuff like debris shields would be very hard to trust over that kind of time frame, along with any electronics that operate hotter then ice.

Yeah basically this. The wealthy person will now only have the wealth of what they have on board the ship, sharing it with everyone else.

It's likely that a future society would make energy the currency of choice. Everything a person does to survive requires energy ... you need to supply power to the chemical manufacturing plants making the fertilizer for the plants that are grown for food. You need to power the irrigation systems, the harvesting and processing equipment, the factories that turn the raw foodstuffs into packaged foods, the vehicles to get the products to market, the lighting and air conditioning in the market, and the home-maker's cooking appliances.

In a society not constrained by material limits (like, for example, an economy with the resources of a solar system to tap into,) one can easily envision an economy arising on the trade of energy credits. Although if you're also not constrained by energy limits (like, for example, if you've disassembled the planet Mercury and turned it all into solar power collectors,) I'm trying to envision what sort of economy would arise from a situation like that ... maybe one based on individual creativity?

That's already happening in our world anyway. Think about youtubers making money simply off the fact that people likes to spend time and watch them.

Anyway ...

What costs would there be in maintaining the ship for centuries? There are no salaries to pay, since it'll all be automated. Basically what you're spending to maintain the ship is the wattage from the ship's powerplant needed to power the repair bots. And what would an insurance company insure? There won't be any space pirates to pay ransom to. And what would a person's great, great, great grandson/daughter/niece/nephew care if great-great-great grandpa took an irreparable cosmic-ray strike to the brain en-route to Zeta Reticuli, or the ship was converted into a cloud of relativistic plasma by a rogue comet? Sure, they might assert that if aforementioned long-dead relative hadn't gone on the trip, they could've passed on an enormous sum of money thanks to the magic of compound interest ... but I'm sure an agency building a sleeper ship would have a carefully-worded legal contract that asserts that the passengers' descendants cannot make claims against the agency in the event of "acts of God;" or else, part of the price of a ticket will be to pay into a trust fund that will pay out to the passenger's descendants in the event that the ship fails due to demonstrable manufacturer's negligence (good luck proving that, though ... if the ship disappears in interstellar space, barring a failure visible by large telescope, that ship is effectively gone forever.) As for the pace of technological advance quickly rendering the ships obsolete ... barring revolutionary new physics, a civilization capable of worrying about sleeper ships may well have exhausted all avenues of technological advance by the time they get around to building such ships. Also, unless the destination is as developed as the solar system, you'd might as well transform the sleeper ship into an orbital colony once you arrive at your destination (since you'll need to refuel it before it can return home, and as has been established earlier ... it's going to need an absolute fuckton of fuel) ... the ship won't be going home again, so who cares if it's a few generations back from the modern state-of-the-art?

The problem is you need to spend all your time building so many reduancies into such a ship that could last a few hundred years. How do you develop technologies that won't break apart from simple wear and tear?

The very first ones will probably be built by huge multi-government cooperatives that won't care so much about profit. The passengers will go aboard with the understanding that they'll likely die before arrival, or get eaten by xenomorphs upon landing. By the time the technology gets cheap enough that people poorer than Donald Trump can afford the price of a ticket, most of the profit will be made from manufacturing the ship and selling spaces ... once the ship launches, the only way it'll cost the company anything is if it visibly blows up en-route, and that failure was obviously the result of some negligence on the part of the contactors who built it (for example, if the flight abruptly ends in a flash of 511 keV gamma rays, that would be fairly damning evidence that it lost antimatter containment.)

Then you reached a problem of how do governments justify spending so much money on very few people who will see the benefits of sleeper ships in their lifetime? Our entire modern economy and public spending is based on fairly short term goals and short term return of investments. How would an elected government even justify that spending when people can't even live long enough to see the success of sleeper ships?

At least the Apollo mission allowed people on earth to experience the joys of success.

[Sky Captain]

I don't think fuel costs would really matter unless starships are powered with direct matter/antimatter annihilation. Fusion fuel is cheap and plentiful in the solar system, it is hardware that is expensive. To seriously consider manned interstellar mission would require well developed space based industry and economy already in place. Something like in the Expanse series where humans have colonized entire solar system, in system travel is easy, ships already travel under constant thrust, there are plenty of entities capable of building large structures in space, large scale mining projects, plenty of experience in operating life support, spaceships and high power fusion engines and so on. Basically all the prerequisites for interstellar mission already are in place.

Gathering several million tons of fusion fuel is easy part compared to engineering difficulties of building a fusion torch engines that can contain what essentially is continuously exploding thermonuclear bomb for years and reliably restart after decades long cruise phase.

To ensure mission success ship would need highly advanced self repair capability basically everything from patching up a debris shield to manufacturing new parts for engines. I think good question would be whether inclusion of few thousand human cryopods and their support stuff would really matter in overall mass budget vs carrying digital copies of human brains if mission is to colonize another star system and start civilization there.