Where Are All The Alien Robots? The Chilling Idea Of Von Neumann Probes
As you know, I’m obsessed about the Fermi Paradox. Where are all the aliens? But an even stranger question is: where are all the robot aliens?
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Created by: Fraser Cain and Jason Harmer
Edited by: Chad Weber
Music: Left Spine Down – “X-Ray”
If you’ve seen at least one other episode of the Guide to Space, you know I’m obsessed about the Fermi Paradox. This idea that the Universe is big and old, and should be teeming with life. And yet, we have no evidence that it exists out there.
We wonder, where are all the aliens?
Ah well, maybe we’re in a cosmic zoo, or maybe the Universe is just too big, or the laws of physics prevent any kind of meaningful travel or communications. Fine. I doubt it, but fine.
As we’ve demonstrated here in our own corner of the galaxy, it’s not our weak fleshy bodies that will be doing the hard work of exploring the Solar System, and eventually the galaxy, it’ll be the robots.
So a better question might be, where are all the robots?
At the time that I’m recording this video, we’re in October of 2016. If you’re watching this on a video device years in the future, the robot uprising and apocalypse hasn’t happened yet.
The most sophisticated walking robots can barely lurch around and they’re laughably slow, 3D fabrication is an inefficient process, and our artificial intelligence devices are pretty dumb, barely able to understand when I ask for directions.
But even so, our robots have helped us explore the Solar System, and helped us see things with cameras that our fleshy meat eyeballs may never experience. Robots from Earth have orbited asteroids, visited comets, observed Mars from orbit and the ground, and even flown past Pluto.
In the coming decades, many new robotic missions will continue this era of exploration, maybe floating in the cloud tops of Venus, sailing the hydrocarbon seas of Titan, flying in the skies of Mars, or exploring the vast oceans under the ice of Europa.
It makes sense then, for us to eventually get around to sending a robotic spacecraft to another star. Based on our current technology, it’ll be incredibly complicated and expensive, but there’s nothing in the laws of physics that prevents it.
And if we’re going to send a robot to another star system, we might as well make it a factory, capable of creating another version of itself. Find an asteroid with all the raw materials to make more robot factories, and send them off to other stars, where they can make more copies, and so on, and so on.
What I’m describing is the concept of a von Neumann probe, named after the mathematician John von Neumann. He was investigating the implications of self-replicating robots in the 1940s, and imagined non-biological “Universal Assembler”, devices that could make copies of themselves.
Von Neumann didn’t apply the idea to spacecraft, but others like Freeman “Spheres” Dyson understood that out in space, there was a nearly limitless amount of raw materials for spacecraft to build copies of themselves.
Even though the Milky Way measures 120,000 light-years across and contains 100 to 400 billion stars, self-replicating robot factories traveling at just 10% the speed of light could colonize the entire galaxy in about 10 million years. That’s the power of exponential exploration.
Think about it. All it takes is for a single clever alien engineer to craft a single robotic factory. That factory builds copies of itself which fly off to other stars. Once they get there, they build more copies of themselves, and so on and so on.
Seriously, in the 13.8 billion years that the Universe has been around, why didn’t a single alien engineer do this?
The cosmologist Frank Tipler concluded that this was such an obvious thing to do that he wrote a paper in the 1980s called “Extraterrestrial intelligent beings do not exist.” Carl Sagan found the argument troubling, proposed that aliens would be concerned with environmental collapse and would restrict the use of this kind of technology.
Why haven’t we received signals from extraterrestrials yet? Maybe because it’s inefficient. It’s much more efficient to send physical probes to communicate with other civilizations.