seti’s search for alien artificial intelligence
SETI is thinking about how to detect and talk to alien computers instead of just alien beings. And that's a lot harder than it sounds.
Just when I try to get out of this topic, PopSci pulls me back in with its review of Seth Shostak’s paper about potential swarms of intelligent alien machines roaming the cosmos and why we should be pondering how to get their attention. The idea is that as advanced civilizations decide to reach out into space, something that would be extremely limited by their resources, they may decide to do what we want to do, and send robots on interstellar journeys. Since these machines would likely be very complex and autonomous to a pretty high degree, they should cluster around young stars and galactic cores to gather new materials to fuel themselves and replicate to explore more of the cosmos, and hence, these stars should be on our watch and contact list because communicative aliens and their intelligent machines may be on the lookout for attempts by others in their galaxy to get in touch with radio signals, lasers, and even physical devices floating in interstellar space.
With all my respect to Dr. Shostak, though, I wouldn’t want to invest all that many resources into trying to talk to alien machinery if I were in his place. It’s not that his idea is unsound, quite the contrary. But the problems are in the details of the subject matter at hand, where they typically lurks. First and foremost, we need to consider a number of design challenges in building interstellar, autonomous explorers and some of the subsequent limits on what they could do. And the same goes for the notion of trying to broadcast binary signals to the alien machine that might be on the receiving end. Even using binary signals, we can’t make two different programs on the same computer talk to each other without using a set of agreed upon standards and translators which decode messages sent using these standards, and turn them into data programs could use. So what are the odds that alien probes that never even heard of our communication standards could catch our binary symbols and decode them into something meaningful to whoever or whatever wrote their software? I’m having a rather hard time imagining what an alien bot would make of an XML file.
Furthermore, who says that alien computers even have to use binary code and logic gates? They might use a pseudo-evolving hardware which uses analog signals, or shielded organic components capable of cognition to guide them. And that’s just what we could think of on our planet, using the grand total of one intelligent life form with less than a century of experience with computational devices using digital code for reference. What could a real alien civilization think of? Without encountering one, we would have absolutely no way of knowing, much less composing messages that could be processed by technology stacks which might have been built across the galaxy from each other, with different goals, ideas, and potential capabilities. We may be better off looking for machines trying to beam their programming across worlds to travel between stars at the speed of light, bouncing between otherworldly computers and satellite towers to the next outpost, tens of thousands of light years out of our reach and incredibly difficult to pin down with any degree of certainty.
Don’t get me wrong, It would be amazing and inspiring to confirm a signal from an intelligent alien entity, even a computer, but since we’re trying to reach extraterrestrials in the real world, we have to be very realistic about our methods and their potential to pay off. Trying to communicate with technology we can only visualize based largely on our own efforts in the computing realm, seems like a non-starter to me. Unless of course, the alien machines in question are smart enough to recognize a deliberate pattern, any deliberate pattern at all, send it back with their own little twist on it just to let us know they heard us, and report back to their masters. Then we may actually be getting somewhere, but we should probably look at potentially habitable worlds where they’re most likely to be exploring potential new habitats and areas of interests for the species which created them in the first place. After all, if we’re looking for rocky planets which could nurture life, why wouldn’t they focus their efforts on the same thing rather than send their machinery to exotic and distant locales for fueling?