Cordial Deconstruction of Stephen Hawking? (Am I So Bold?)
Posted by Karl Withakay on April 26, 2010
Would you drive to Alaska to buy gasoline? Stephen Hawking seems to think you might if your local gas station ran out.
Here’s my take on the ID4/ hostile aliens thing:
(And here is where I dare to Cordially Deconstruct the position of someone who is much, much, much smarter than I am)
There’s something on the order of 100 billion galaxies in the known universe, and there’s something on the order of 100 billion stars in each of those galaxies. We’re just beginning to scratch the surface of figuring out how many of those stars might contain planets and how many of those planets or their moons might be remotely habitable by life as we know it. I think it would be wise to assume that some forms of extremophiles could survive on worlds more hostile than what we conservatively call habitable. And although we don’t really have any reasonable clue for estimating the probability of life arising on a suitable world, let alone the odds of intelligent life developing, 10,000 billion, billion stars is a lot of stars (10^20), and that’s a lot of spins on the roulette wheel of life to hit the jackpot only once. In the absence of actual data, it seems reasonable to speculate that there’s life elsewhere in the universe, and some of it is probably more advanced than we are.
That being said, it also seems likely to me that inter-galactic space travel isn’t particularly likely, and we don’t have to worry about whether ET is friendly or not.
You may think this is modern arrogance, but despite mysteries like dark energy and dark matter, we have a pretty good idea of how the universe works, and it looks like the universal speed limit (can not obtain) for things with mass is the speed of light. The practical effect of this limit is that inter-galactic travel would take an incredibly long time to get anywhere not in you own star system. Intergalactic travel would also take an impractically large amount of energy if you wanted to travel at any velocity approaching a significant percentage of the speed of light. Even if we speculate the discovery of some way to travel faster than the speed of light, it seems reasonable to also speculate it would extremely (prohibitively) energy intensive.
So what might we have here in an ultra-advanced, space faring, alien species? We have ETs that have no motivation to travel to other stars for anything other than esoteric knowledge gathering that probably won’t be of any use to the folks back home anyway, since they’ll likely all be long dead by the time the explorers got back. Listen, if you have the energy resources to travel across the galaxy (either at sub-light or superluminal velocity), you don’t need to plunder the resources of other worlds; you’ve got resources coming out of your ying tang, and you’ve got the technology to do whatever you need with those resources. You’d be better off just terraforming some reletively nearby world rather than traveling across the galaxy to plunder a distant Earth-like planet.
Traveling across the galaxy to plunder the Earth’s resources would be like me driving to Alaska from Missouri to buy gas if my local filling station ran out. Why bother if I already have the resources to get there?
5-2-10: See the followup post here: Followup: Energy Requirements of Interstellar Travel