Prediction is very difficult, especially about the future.
If you’re a science fiction writer, one of the things you do is try to predict what future technologies will come along. If you’re not writing hard science fiction, this is relatively easy. You just come up with a cool capability and throw in some plausible sounding technical jargon. It’s like adding a magical ability in a fantasy story. As long as you make sure the rules of magic are consistent, you’re in business.
But if you are aiming for harder science fiction, or you’re a futurist, what guiding principles can you use for making grounded predictions? The difficulty level is actually much harder when making near term predictions, partly because your predictions will be assessed for accuracy in your lifetime, but also because it requires a pretty thorough immersion into current technologies, how they work, what the trends lines are, and what room exists for future improvement.
It gets a little easier for making longer term predictions, because instead of trying to figure out what technical breakthroughs will happen in the next few years, you’re focusing on what might eventually be possible, where the laws of physics may eventually be the deciding factor.
Of course, we could well discover new laws of physics down the road, and who knows what capabilities that new knowledge might enable? As Arthur C. Clarke once observed, any sufficiently advanced technology becomes indistinguishable from magic for an observer from a less developed society. We don’t know most of what we don’t know, and attempting to make predictions about future knowledge is basically just wild guessing.
But if we’re trying to be somewhat grounded, keeping our predictions to things that have a reasonable chance of being true, then it might pay to stick to known science, or at least science that isn’t too speculative. When thinking about this, it pays to remember what technology actually is, which is the manipulation of natural forces for our benefit. If the future technology you’re imagining isn’t based on some natural force, or a combination of natural forces, then you’re essentially positing magic.
This might be a little clearer if we think about the earliest technologies. Many animals use sticks as tools to get food from out of tight places, what Douglas Adams called “stick technology”. Early humans developed a technology no other animal had developed by taming fire and using it for cooking, protection, and many other purposes. And starting with breeding dogs from wolves, humans began domesticating a number animals and for a variety of purposes and controlling how plants grow for food, again making use of existing natural resources.
If you don’t think these things count as technology, then consider plumbing. Developed by ancient societies, plumbing makes use of the natural tendencies of water (hydraulics) for human convenience. Or consider electricity, which Larry Niven and Jerry Pournelle in their novel, Lucifer’s Hammer, referred to as tamed lightning.
A modern car is built to harness natural forces: electricity, air flow, the combustive reaction of gasoline (refined oil, which is stored concentrated solar energy), and mechanical force. Without these natural forces, there can be no car. Or any other kind of technology.
For future technologies, this means we need to find plausible natural forces which could be used to construct them. It’s easy to imagine something like, say, a Star Trek style teleporter, until we try to envision what kind of system could deconstruct, track, transmit, and reconstruct the 7 X 1027 atoms in a human body along with their precise physical configuration. Even if we could come up with a computational system that could store that much information and get around quantum no-clone theorems, transmitting it using any variant of electromagnetism might take orders of magnitude longer than the age of the universe. It seems difficult to imagine such a system without resorting to new physics, in other words without reaching for magic.
I think a good starting point when evaluating potential future technologies is to ask, does it happen in nature? Or do all of its components happen in nature? Once we observe it in nature, the question ceases to be whether it’s possible, but whether humans can do it? Historically, assuming that the answer to that last question is “no” hasn’t been a winning bet.
By this simple metric, it should have been obvious to people in the 19th century that eventually flight would be possible, since birds were doing it everywhere. And the fact that meteors and other natural phenomena routinely exceed the speed of sound should have clued in early 20th century pilots that aircraft would eventually be able to do so.
So, what does this mean for individual future technologies? Well, organic life is built on molecular nanomachinery, which seems to indicate that nanomachines will definitely be possible at some point. (Nanomachines that exist in attack swarms? Not so much. What would be the means of propulsion and levitation for such swarms?) An interesting question is whether manufacturing nanomachines could happen without mutations creeping in, something evolved nanomachines haven’t accomplished.
Intelligent machines? If you accept that we are intelligent machines, just evolved ones, then the question is how long it will take for us to build engineered intelligent machines. Another question is what the potential might be for those engineered intelligences. Many people seem to assume that they could have the capacities of human brains paired with the speed of silicon processors, making them super god-like entities.
But nothing like this yet exists in nature, and we may well find that achieving the necessary capacities requires inescapable trade-offs in performance. (For instance, maybe that much information density requires water cooled operation.) While human minds are highly unlikely to be the most intelligent systems that can exist, we shouldn’t assume that AI (artificially intelligent) minds will automatically be thousands of times more powerful than the human variety, particularly a human brain that has itself been integrated with technology.
The criteria become more problematic when we consider things like warp drives, hyperspace, or other putative FTL (faster than light) technologies. We have no evidence for anything in nature that travels faster than light, except for a couple of exceptions that don’t seem like much help.
One exception is quantum entanglement, but whether it counts as FTL seems to depend on which interpretation of quantum mechanics you favor, and it allows for no actual communication. (If you try to manipulate the quantum state of one of the entangled particles, you don’t affect its partner, you only destroy the entanglement.)
Another exception are galaxies beyond our cosmological horizon. Due to the expansion of the universe, they’re moving away from us faster than light (from our vantage point). But those galaxies are causally disconnected from us. Since they moved over the horizon, they can have no affect on us, nor us on them. In other words, they’re now effectively in a different universe. No objects that can causally interact have ever been observed to move faster than light relative to each other.
People sometimes talk about concepts such as Alcubierre Drives or wormholes. But these concepts require speculative phenomena such as negative energy or imaginary mass to exist, which puts us back in the realm of new physics, in other words, speculative guessing.
And under special and general relativity, any FTL capability, by whatever means, effectively allows for time travel. Is time travel possible (that is, aside from our normal forward progression)? Again, we have no observable phenomena in nature that seems to do it, nor any identifiable method that could built on to do it. And the absence of tourists from the future seems to hint that time travel to arbitrary destinations isn’t possible. (People sometimes imagine a code of ethics that prevents time travelers from making their presence known, but the idea that such a code would hold for all time travelers from all future societies seems improbable.)
But the criteria does allow for some pretty mind bending concepts such as artificial planets, stars, even black holes, not to mention megastructures such as Dyson swarms. All of which are rarely seen in science fiction.
What do you think? Do you agree that looking for natural phenomena is a good criteria to evaluate the possibility of future technology? If not, what additional or alternative criteria would you add?