Toward the end of the TV series Game of Thrones, a big long (multi-year) winter was coming, and while everyone should have been saving up for it, they were instead spending lots to fight wars. Because when others spend on war, that forces you to spend on war, and then suffer a terrible winter. The long term future of the universe may be much like this, except that future winter will never end! Let me explain.
The key universal resource is negentropy (and time), from which all others can be gained. For a very long time almost all life has run on the negentropy in sunshine landing on Earth, but almost all of that has been spent in the fierce competition to live. The things that do accumulate, such as innovations embodied in genomes, can’t really be spent to survive. However, as sunlight varies by day and season, life does sometimes save up resources during one part of a cycle, to spend in the other part of a cycle.
Humans have been growing much more rapidly than nature, but we also have had strong competition, and have also mostly only accumulated the resources that can’t directly be spent to win our competitions. We do tend to accumulate capital in peacetime, but every so often we have a big war that burns most of that up. It is mainly our remaining people and innovations that let us rebuild.
Over the long future, our descendants will gradually get better at gaining faster and cheaper access to more resources. Instead of drawing on just the sunlight coming to Earth, we’ll take all light from the Sun, and then we’ll take apart the Sun to make engines that we better control. And so on. Some of us may even gain long term views, that prioritize the very long run.
However, it seems likely that our descendants will be unable to coordinate on universal scales to prevent war and theft. If so, then every so often we will have a huge war, at which point we may burn up most of the resources that can be easily accessed on the timescale of that war. Between such wars, we’d work to increase the rate at which we could access resources during a war. And our need to watch out for possible war will force us to continually spend a non-trivial fraction of our accessible resources watching and staying prepared for war.
The big problem is: the accessible universe is finite, and so we will only ever be able to access a finite amount of negentropy. No matter how much we innovate. While so far we’ve mainly been drawing on a small steady flow of negentropy, eventually we will get better and faster access to the entire stock. The period when we use most of that stock is our universe’s one and only “summer”, after which we face an unending winter. This implies that when a total war shows up, we are at risk of burning up large fractions of all the resources that we can quickly access. So the larger a fraction of the universe’s negentropy that we can quickly access, the larger a fraction of all resources that we will ever have that we will burn up in each total war.
And even between the wars, we will need to watch out and stay prepared for war. If one uses negentropy to do stuff slowly and carefully, then the work that one can do with a given amount of negentropy is typically proportional to the inverse of the rate at which one does that work. This is true for computers, factories, pipes, drag, and much else. So ideally, the way to do the most with a fixed pot of negentropy is to do it all very slowly. And if the universe will last forever, that seems to put no bound on how much we can eventually do.
Alas, given random errors due to cosmic rays and other fluctuations, there is probably a minimum speed for doing the most with some negentropy. So the amount we can eventually do may be big, but it remains finite. However, that optimal pace is probably many orders of magnitude slower than our current speeds, letting our descendants do a lot.
The problem is, descendants who go maximally slow will make themselves very vulnerable to invasion and theft. For an analogy, imagine how severe our site security problems would be today if any one person could temporarily “grow” and become as powerful as a thousand people, but only after a one hour delay. Any one intruder to some site who grew while onsite this could wreck havoc and then be gone within an hour, before local security forces could grow to respond. Similarly when most future descendants run very slow, one who suddenly chose to run very fast might have a huge outside influence before the others could effectively respond.
So the bottom line is that if war and theft remain possible for our descendants, the rate at which they do things will be much faster than the much slower most efficient speed. In order to adequately watch out for and respond to attacks, they will have to run fast, and thus more quickly use up their available stocks of resources, such as stars. And when their stocks run out, the future will have run out for them. Like in a Game of Thrones scenario after a long winter war, they would then starve.
Now it is possible that there will be future resources that simply cannot be exploited quickly. Such as perhaps big black holes. In this case some of our descendants could last for a very long time slowly sipping on such supplies. But their activity levels at that point would be much lower than their rates before they used up all the other faster-access resources.
Okay, let’s put this all together into a picture of the long term future. Today we are growing fast, and getting better at accessing more kinds of resources faster. Eventually our growth in resource use will reach a peak. At that point we will use resources much faster than today, and also much faster than what would be the most efficient rate if we could all coordinate to prevent war and theft. Maybe a billion times faster or more. Fearing war, we will keep spending to watch and prepare for war, and then every once in a while we would burn up most accessible resources in a big war. After using up faster access resources, we then switch to lower activity levels using resources that we just can’t extract as fast, no matter how clever we are. Then we use up each one of those much faster than optimal, with activity levels falling after each source is used up.
That is, unless we can prevent war and theft, our long term future is an unending winter, wherein we use up most of our resources in early winter wars, and then slowly die and shrink and slow and war as the winter continues, on to infinity. And as a result do much less than we could have otherwise; perhaps a billion times less or more. (Thought still vastly more than we have done so far.) And this is all if we are lucky enough to avoid existential risk, which might destroy it all prematurely, leading instead to a fully-dead empty eternity.
Happy holidays.
The opening scenes in Star Wars VII (the first of the new ones) symbolized this very well. We see amazing futuristic technology, but everything is dwarfed by the enormous wrecks of battleships. We see people living in a time when vast resources are clearly available, but used for war, while they live on the edge of starvation.
I'm pretty sure I said something more specific than that.