Stephen Hawking is telling us to be afraid, to be very afraid. In some sort of Mars Attacks/Independence Day nightmarish vision of the future he suggests:
“If aliens visit us, the outcome would be much as when Columbus landed in America, which didn’t turn out well for the Native Americans”
Thanks for that, Stevey-boy. I mean clearly, if they have the technology to get to us before we have the technology to get to them, it’s likely that we’ll be cousin Cletus to their Eustace Tilley, but there’s no need to get all doom and gloom about it. Let’s not just ignore the possibility that Star Trek might be how it turns out. Please?
And anyway, his dire warning does rather ignore the obvious question… “Where the hell is everybody, anyway?”
In 1950 the physicist Enrico Fermi asked that same question in what’s become known as Fermi’s Paradox. Essentially he asked “If there are so many potentially habitable planets, signs of extra terrestrial life should be common. So. Where are they all?”
In 1961 Frank Drake prepared an equation that attempted to address this question by trying to estimate how many alien civilisations are out there, able to communicate with us, at any one time. Put most simply he took the number of stars in the Milky Way and slowly whittled it down by the fraction that had planets, the fraction of those that had planets that could potentially support life, the fraction of those that actually develop life, the fraction of those that develop intelligent life, and finally the fraction of those intelligent lifeforms that develop technology that we could identify.
The final parameter in the equation (called L) is the length of time such civilisations survive to release detectable signals into space. Tying all of these factors together gives you an estimate of the number of civilisations that we could/should be hearing from, right now.
Unfortunately using Drake’s equation the only way to satisfactorily answer (for some value of satisfactory) Fermi’s Paradox is to make L painfully short.
In the eighties, particularly among the sandal wearing CND types, it was popular to assume that L was short because intelligent life was inherently self-destructive. For them this seemed obvious because human life on earth had only been producing identifiable electro-magnetic radiation for 100 years, yet within the first 50 years of those 100 we had invented and detonated the atomic bomb. Not for us the utopia of vast, peaceful, galactic federations, but instead a miserable existence that went from soul crushing feudal poverty to mutually assured destruction in a few short centuries.
In 1996 a guy by the name of Robin Hanson formalised the approach to Fermi’s Paradox in logic as “The Great Filter“. In it he reached the conclusion that if indeed it is easy to evolve to the current state of human intelligence then our future must be, by logical extension, extremely bleak.
Posing this as a logic problem and then reaching that sort of conclusion has lead many people to attempt to provide a rationalisation. Now that the fear of nuclear holocaust has all but passed we find ourselves looking at other societal ills to explain the inherent shortness of L; cf. “Why We Haven’t Met Any Aliens” from 2006, blaming video games (I can’t help thinking if the author of that particular piece had been from the 18th Century he would have blamed it on the effects of Gin).
Frankly it’s all a bit bloody miserable.
To which I say sod formal logic. I like to think that they are out there, that they are on their way, and that when they get here they’ll be like Jeff Goldblum and Jim Carrey in Earth Girls Are Easy. Furry, horny and dumb as a box of rocks.
But that’s just my view.