perfidy

Where are they? The Fermi Paradox has lept out at me twice in as many days. First off, a post on the arXiv blog about some new research into the FP.

Their approach is to imagine that civilisations form at a certain rate, grow to fill a certain volume of space and then collapse and die. They even go as far as to suggest that civilisations have a characteristic life time, which limits how big they can become. In certain circumstances, however, when civilisations are close enough together in time and space, they can come into contact and when this happens the cross-fertilisation of ideas and cultures allows them both to flourish in a way that increases their combined lifespan. Bezsudnov and Snarskii point out that this process of spreading into space can be easily modelled using a cellular automaton. And they've gone ahead and created their own universe using a 10,000 x 10,000 cell automaton running over 320,000 steps. The parameters that govern the evolution of this universe are simple: the probability of a civilisation forming, the usual lifespan of such a civilisation and the extra bonus time civilisations get when they meet. The result gives a new insight into the Fermi Paradox. Bezsudnov and Snarskii say that for certain values of these parameters, the universe undergoes a phase change from one in which civilisations tend not to meet and spread into one in which the entire universe tends to become civilised as different groups meet and spread. Bezsudnov and Snarskii even derive an inequality that a universe must satisfy to become civilised. This, they say, is analogous to the famous Drake equation which attempts to quantify the number of other contactable civilisations in the universe right now.

So the question is, do we live in a world where intelligent species are too far apart to cross-pollinate, and survive; or one where they are, but it hasn't happened yet?  This is interesting, and is somewhat in line with my own thinking - though they are completely ignoring the possibility of BEMS and conflict, and supposing that intelligent entities in space are all bug-eyed Sagans who will get along famously.  I'm not saying they can't, but it isn't a sure thing.  Read Killing Star if you're uncertain about that one.  Pay special attention to the Central Park analogy. Interesting spin on the Fermi Paradox - but nothing really outre. Charles Stross, in his recent post Mediocrity (a sequel to the thrilling post Insufficient Data)

In general, there are two classes of solution to the Fermi paradox; ones that assume that we are unique special snowflakes in an empty cosmos, and those that postulate that intelligent species are common, but some kind of mechanism stops them from colonizing interstellar space. If we look at the second problem set, and broaden the focus ... well, intelligent species emerge as components of a biosphere bound to a particular planetary habitat. We humans are land-dwellers on Earth in the later high-oxygen period; conditions on earth even one billion years ago would have been rapidly fatal for an unprotected human, and even today, survival on 90% of our planet's surface area is contingent on the availability of cultural artefacts like boats (80% is water) or clothing (for protection in hostile climates). So the real question isn't, "can intelligent life colonize other star systems?" so much as "can intelligent life propagate itself, and its supporting biosphere and technosphere to run in alien environments? Which is a very different question. Call it the Ark Problem; if your name is Noah and you're going on a one-way trip to another world, how big an Ark do you need (and how many specimens per speciality, be they biological or technological)?

There is of course the not-answer to the Fermi Paradox - the simulation hypothesis - which argues that there are exactly as many intelligent species as the simulation designer decided to throw in the box with us, and no more. But then, it gets interesting.

It's that danged principle of mediocrity that's causing all these problems. It shows up in the Fermi Paradox, it turns up in the Simulation Argument, it turns up like a bent penny in all sorts of places — it's a big problem for the standard model of spacetime, once you start digging into the Boltzman Brains paradox (for a quick intro, look here or here). Indeed, it seems to me to be a corollary of the weak anthropic principle.

I'd never heard of the Boltzmann Brain paradox - I followed the links.  From the first:

The idea Don put forward is this: there’s us, the ordinary observers (OO’s) in the world, who have achieved a certain stature after billions of years of evolution in the universe, and are now capable of making quite refined (or so we think) observations of the universe. Andre Linde called OO’s “just honest folk like us.” We’ve made it as a species, man- and womankind, and we’re figuring ou the really deep things that are going on like the Big Bang, genetics, and all the rest. Then, though, there are the BB’s in the universe: Boltzmann Brains. Random fluctuations of the fabric of spacetime itself which, most of the time, are rather insignificant puffs which evaporate immediately. But sometimes they stick around. More rarely, they are complex. Sometimes (very very rarely) they are really quite as complex as us human types. (Actually, “very very rarely” does not quite convey just how rare we are talking now.) And sometimes these vacuum quantum fluctuations attain the status of actual observers in the world. But, the rarest of them all, the BB’s, are able to (however briefly) make actual observations in the universe which are, in fact, “not erroneous” as Don Page put it.

Over time - in a sufficiently long-lived universe - BB's should predominate.  (More so if, god forbid, they should learn how to reproduce.)

The thing is, when you start talking about very very…very rare things like Boltzmann Brains, you are talking about REALLY long times. Much longer than we’ve had on earth (and I mean 4.5 billion years) by many orders of magnitude. Numbers like 10 to the 60th years were being batted around like it was next week in this talk. By those times, all the stars and all the galaxies have gone out, and gone cold, and space has continued to expand exponentially and things are long past looking pretty bleak for the OO’s still around, who (we presume) need heat and light and at least a little energy of some sort to survive, even if we are talking about very slow machine intelligence (even slower than humans for example). So eventually, the mere fact that there is, at these long times, just oodles of space in the universe means that the BB’s become more and more common (even if they are rare) and eventually dominate the, uh, intellectual landscape of the universe. Of course this immediately raises all sorts of questions, such as mind/matter duality, the nature of reality and consciousness and multiple consciousnesses, perceived versus objective independent reality. Not to mention whether our “universe” is the only one.

And from Wikipedia, more on the Boltzmann Brain:

Boltzmann proposed that we and our observed low-entropy world are a random fluctuation in a higher-entropy universe. Even in a near-equilibrium state, there will be stochastic fluctuations in the level of entropy. The most common fluctuations will be relatively small, resulting in only small amounts of organization, while larger fluctuations and their resulting greater levels of organization will be comparatively more rare. Large fluctuations would be almost inconceivably rare, but this can be explained by the enormous size of the universe and by the idea that if we are the results of a fluctuation, there is a "selection bias": We observe this very unlikely universe because the unlikely conditions are necessary for us to be here, an expression of the anthropic principle. This leads to the Boltzmann brain concept: If our current level of organization, having many self-aware entities, is a result of a random fluctuation, it is much less likely than a level of organization which is only just able to create a single self-aware entity. For every universe with the level of organization we see, there should be an enormous number of lone Boltzmann brains floating around in unorganized environments. This refutes the observer argument above: the organization I see is vastly more than what is required to explain my consciousness, and therefore it is highly unlikely that I am the result of a stochastic fluctuation. The Boltzmann brain paradox is that it is more likely that a brain randomly forms out of the chaos with false memories of its life than that the universe around us would have billions of self-aware brains. The rationale behind this being paradoxical is that, out of chaos, it is more likely for one instance of a complex structure to arise than for many instances of that thing to arise. This ignores the possibility that the probability of a universe in which a brain pops into existence, without any prior mechanism driving towards its creation, may be dwarfed by the probability of a universe in which there are active mechanisms which lead to processes of development which (given a starting state that is unlikely but not as unlikely as the spontaneous appearance of a brain with no precursor) offer a reasonable probability of producing a species such as ourselves. In a universe of the latter kind, the scenarios in which a brain can arise are naturally prone to produce many such brains, so the large number of such brains is an incidental detail.

Fascinating. Weird to imagine that after the heat death of the universe, and trillions of years after the death of all OO's like us, Boltzmann Brains may still be there, observing.