We have slim chance, suggests the British physicist Stephen Wolfram, of distinguishing an extraterrestrial artifact from a natural celestial object.
According to Wolfram, if someone beamed our own 21st-century communication signals at us from space we would be hard pressed determining whether they were artificial or natural. So what chance do we have of distinguishing an ET communication from the general background radio static of the cosmos?
ET artifacts coordinated by computers would look far more like a natural artifact. It is easy to distinguish a technological artifact such as a car from a natural object such as a tree. The tree is far more complicated.
But, says Wolfram,”this is simply because our technological artifacts are primitive. As they become more complex – with computer processors enabling them to make a moment-by-moment decisions – they will begin to look just as complex as trees and people and stars.”
If Wolfram is right and ETs are out there but we will not be able to recognize them – either in their communications or their artifacts – then of course they could be here in the Solar System and we would not have noticed.
In Wolfram’s view, everything in the Universe is the product of a computer program. In fact, he imagines an abstract cyber-universe of all conceivable computer programs, all the way from the simplest up to the most complex. This “computational universe” contains everything from the Apple Macintosh operating system to a program for creating a faster-than-light starship.
Wolfram believes he has found nature’s big secret – how it generates the complexity of the world, everything from a rhododendron to a tree to a barred spiral galaxy by applying simple rules over and over again as a simple computer programs.
Wolfram came to this remarkable conclusion in the early 1980s when he discovered that the simplest kind of computer program – known as a cellular automaton – can generate infinite complexity if its output is repeatedly fed back in as its input…