Our sun is a relatively young star, and one of millions yellow G-type main sequence stars in the galaxy. A lot of these are surrounded by planetary systems, with one or more large bodies in their respective Goldilocks zone where conditions are just right to support a thriving biosphere. As far as we know the process that kick-started organic life on earth is not something unique to our planet, and can and does happen out there in space with high probability. By all counts the galaxy should be able to support a multitude of thriving planetary ecosystems, most of which should eventually produce an intelligent species. The interesting part of the equation is that most of the main sequence stars out there are older than our sun, and have planets that cooled down and were ready to sprout life much earlier than Earth. So there ought to be quite a few technologically advanced alien civilizations in the universe, and statistically some of these ought to be located in our immediate stellar neighborhood.
It would make sense that an independently evolved alien civilization would progress in a manner to our own. The exact details of their technological devices might differ from our significantly, as could the order of discoveries and scientific breakthroughs. However it is a fair guess that their civilization would follow an exponential growth pattern like ours did: with slow agricultural build up, quick industrial era exploding into information age and beyond. Many of them should have reached that stage long before us and moved far beyond us on the exponential curve.
The interesting question is this: if there is such a high probability of existence of one or more very advanced civilizations in this corner of galaxy, why haven’t we discovered sings of its activity yet? Or why haven’t they intercepted our radio noise and come visiting yet? This seeming contradiction is known as the Fermi Paradox.
Physicists and philosophers much smarter than me have already developed many varied and interesting hypothesis aiming to explain this paradox but it is always fun to muse about such things. So let’s see what we can say about it as Science Fiction fans and science enthusiasts.
The basic problem we have is that we are so far been incapable to detect any alien activity anywhere in the universe. However if we are trying to find aliens more advanced than us, chances are we won’t see them blasting radio communications into the void. If they have a few centuries of development on us, they have likely moved up on the Kardashev scale and rolled up their native solar system into a Matrioshka brain. So what we ought to be looking for are not not noisy spots, but rather quiet dark holes that radiate a lot of waste heat – a classic tale-tale of a Dyson Swarm like construct. So far we haven’t seen any of these out there.
Granted, our main search tool is the SETI project which is severely limited and criminally underfunded. The actual area of the sky we can “watch” at the same time is incredibly narrow. In essence the way we search for alien civilizations is akin to searching for a needle in a hay stack, by poking at it randomly with another needle. Only statistically there should be a lot of needles in there, so we will eventually poke into something that is not hay – or at least that is the plan.
I mentioned the exponential progress curve at the beginning of this post for a reason. Here is an interesting observation: assuming all other factors being equal, by the time a civilization starts blasting radio waves into the void of space, they are already on their way towards singularity. Consider our own situation: in terms of space flight, we are very, very backwards. We haven’t even explored our own moon properly and our knowledge of our solar system is based mostly on information gathered by unmanned drones. And yet, at this very moment we can already feel the pull of technological transcendence. The pace of progress is ramping up, and big technological breakthroughs happen every few months. We are rapidly breaking down computational barriers, we are extending Moore’s law beyond the point of feasibility and we are constructing high fidelity, high bandwidth communications array for less every day. Our lives two or three decades from now will be unrecognizably different.
So my little pet hypothesis is that by the time a sentient civilization starts to look to the stars as a realistic destination of travel they might be mere few decades away from the omega point after which everything changes. We are developed enough to understand this process and the inevitable turning point, but have no idea what may lie beyond it. With out current grasp of physics we imagine digital transcendence as sort of an inward turtleing move in which a civilization deconstructs their immediate environment to encircle their home star with computronium array. But this may actually not be what happens out there. The fact that we haven’t found any Dyson style mega-structures in the sky might be a good indication that the super-advanced aliens are past that stage. Or that they never actually attempted to build large scale computational arrays here, because our universe is not inherently stable.
Recently physicists finally caught and measured the elusive Higg’s Bosson, and based on the preliminary experimental measurements established that our universe is very likely to be contained a long lived, but not completely stable region of space. It is entirely possible that we exist in a bubble of “false” vacuum which can at any point collapse to a more stable state. Such a collapse would propagate through space at light speed, and subtly altering the fundamental forces that bind our universe together, and as a result changing how subatomic particles interact with each other. In other words, life, universe as we know it would be winked out of existence. In fact, this false-vacuum collapse might have already occurred somewhere beyond our light cone, and there is an ever expanding bubble of pure chaos rupturing stars at the speed of light en-route towards the milky way at the speed of light. Which means that we won’t know about it until it is to late, and even if we had some warning, there is no way for us to escape it…
But, a civilization which has achieved digital enlightenment long before our ancestors climbed down from the trees could theoretically have had ample time to predict the imminent false vacuum collapse and figure out a way to “migrate” to a more stable universe. It is very likely that as aliens transcend the physical and achieve immortality via digitization they all realize our universe is not a sustainable system and get the fuck out. And it probably takes them less than a century or two from the point at which they start blasting radio waves into the sky.
If SETI is ever going to find traces of alien civilizations, they will likely be inactive post-transcendence fossils – discarded, incomplete, de-synchronized Dyson swarms surrounding forgotten stars if we are lucky. Maybe some of our neighbors were nice enough to leave us some sign-posts of where we could find them. Perhaps there is some alternate, optimal plane of existence where we can meet all the past post-singularity civilizations that originated in a variety of unstable universes. Or perhaps the fate of all civilizations is an ultimate solipsism: create a pocket universe with optimal physics for computation, migrate inside and iterate until the end of time. I guess we will find out soon enough.