Okay, so those of you who know me know I love Fermi’s Paradox: “Where are they?” (And by “they” I mean extraterristrials, not some other they, like, physics and literature majors. I guess I’m more attuned to noticing that later odd specimen, but you’d be amazed at how popular that combination is.) One variant of the answer to Fermi’s Paradox is simply that the E.T.s are so advanced that they don’t really give a poop about us. Today I was pondering what could possibly make an E.T. think that we are so boring, so ordinary, that we were like specks of nothing in their eyes. And I thought, well maybe there is a computer science meets physics answer to this question!
A few years ago, we had this beautiful complexity class, BPP, of stuff that our ordinary computers could handle. Today we speculate that there is a slightly large complexity class which “ordinary” (and by ordinary I mean super challenging today, but possibly simple in the future) computers can handle: BQP. Now, suppose that this continues. As we probe deeper into the laws of physics we discover that we gain more and more computational power. We could even speculate that, there is a point where our physical laws allow us to solve NP-complete problems effeciently (that popping sound you just heard was Scott’s head.) As Lance and Scott has so beautifully pointed out, the consequences of this would be a reduction of large chunks of our culture to tractable problems. So if it were indeed true that physical allows for the efficient solution to NP-complete problems, then a society like ours, with our piddly classical computers and even our piddly future quantum computers, and our silly little things like the plays of Shakespeare are pretty boring objects. Large cunks of our society become nothing more than something which can be achieved on an alien laptop computer. Why bother visiting the Earth when not much interesting is occuring there which cannot be made a tractable problem on your computer.
Now of course, we know that NP is just one of a tower of higher and higher complexity classes (I would called it a zoo, but then I’d have to believe that a flood was near and that soon some some brave complexity theorist (who has a severe drinking problem) would have to pack up all the complexity classes, and their complements, into an ark in order to survive a flood which whipes out all other complexity theorists.) So even these luckily aliens who have access to a NP-complete solving computer and who therefore totally ignore us, might have their own Fermi Paradox? Are their levels of aliens all ignoring their lesser beings because of the weakness of the complexity classes their computers can efficiently solve?
O brave new quantum world!
Dave, it occurs to me that your argument can also be applied theologically. I.e., the reason God doesn’t care about human suffering is the same reason we don’t care about hadrons getting smashed to bits in particle accelerators — because the system in question is too trivial for its “suffering” to be of any concern to beings with vastly more computational power.
It could be the case that any civilization will deplete the natural resource around it and then kills itself before it is capable of getting sophisticated enough to traveling far enough. What we can hope for is to discover the artifacts of the others one day. But will we stay long enough to discover these artifacts that must be sturdy enough to remain intact by the time we reach it? If we have been “seeded” far enough from the others then we will probably never see the others and the others will probably never see us either… Oh, and let’s hope the Universe is not expanding too fast!
Some astronomers argue that the anthropic principle is more true than you might have hoped, and that there may have never been any other life in the entire galaxy, not even bacteria. The arguments are based on things like the availability of “metallic” elements (anything other than hydrogen and helium), the likelihood of favorable orbits, and the absence of events that can sterilize planets.
Perhaps they have very short life spans. 10 or 20 years (obviously this could be much more if they were from a distant star). If they had the technology to reach, say, 0.9999c, then they would hardly age on the trip. This cannot be said for those that remain on their homeworld, and perhaps like us, they have no desire to return to their homeworld and find everyone they know has died of old age.
> the same reason we don’t care about hadrons getting smashed to bits in particle accelerators
But we *do* care about what happens when we smash hadrons. And I think, if there were aliens, there should be enough ‘bureaucratic aliens’ who would care about classifying our planet and its inhabitants.
I think we should start using the expression “God-E.T. duality” to describe substitutions of E.T.s into theological arguments and substitutions of God into alien discussions. I am very fond of “argument by alien” in ethical arguments.
hey Dave, just out of curiosity, were people allowed to major in Literature (as the only major) at Tech? I vaguely recall that the answer is yes, but no one ever goes to Caltech only to major in Literature, as you have to take so much physics and math anyway. I am sort of jealous of you because I wish I did something else (other than biology) at Caltech. I did take a few classes not required of me (remember we were in Ay 20 together?) but I still feel like I could have “explored” more.
Yep there was a literature major at Tech. My degree is Physics/Literature, aka the no salary major. I went to a commencement a few years ago and there were three Physics and Literature majors. Crazy, eh?
Oh I remember Ay20! Do you remember the prof falling off of the stage and slamming into the wall?!
no, I don’t remember the prof-falling incident. I remember the last homework assignment, which had to do with discussing the possibility of extra-terrestrial life and how we would recognize/define/communicate with it.
I just saw “Contact,” by the way, at the recommendation of other scientists and of scriptwriters. I thought it was very well done… especially the parts where the guy tries to steal credit for her work. Whoever wrote the book really did a good job.
This is a really cool idea. Although it doesn’t explain where all the BPP (or BQP) aliens are.