From: Karl H. Schreyer (karlschr@northnet.org)
Date: Wed Nov 06 1996 - 16:15:58 MST
----------
> From: Steve Witham <sw@tiac.net>
> To: extropians@extropy.org
> Subject: Cryptocosmology--Dirt does Not Compute?
> Date: Tuesday, November 05, 1996 12:59 AM
>
> [Hint to readers: if you don't like how this message is going, skip a
> couple paragraphs, it wanders a lot. Try to catch the references to
> John Gilmore, Blake on scale, Neitzsche on pretenders to science like me,
> and the Big Iron Crystal. The Sun seen as a refrigerator. Plus, the
> Other Cryptocosmology Quip. --Steve]
>
> >From: hanson@hss.caltech.edu (Robin Hanson)
> >Date: Tue, 15 Oct 96 10:41:50 PDT
> >Subject: Great Filter, Low Profile, Cryptocosmology
> >
> >[...]
> >
> >If one looked at the inards of a very advanced computer, then if one
> >intercepted a "long" communications channel, where the cost to
> >transmit was large compared to computation costs at either end, then
> >yes it should look like random noise relative to a high entropy state
> >of that channel. But this observation is a long way from showing that
> >the innards of this computer should look like the stars and dirt we
> >see.
>
> Well, right, that's even less than circumstantial. Motive and method
> are also needed. I'm saying the motive is just that hiding is necessary.
> Whether there's a possible method...because we're talking
> about civilizations more advanced than our own, we can only ask, can we
> prove that it's *not* possible to be computing with (what looks like)
> dirt?
>
> By the way, in case I wasn't clear, it isn't that dirt, or any of our
> particular surroundings, are what I would expect to see. "Dirt" is just
> my code word for whatever science would lead us to expect are natural
> things to see at this stage in the evolution the universe.
>
> If looking like "dirt" is a great advantage, and it's possible,
> then I would expect advanced civilizations to look like dirt.
>
> >As you point out, all that sunlight streaming away seems
> >inefficient.
>
> Yes. But maybe that's just the cost of hiding. Our civilization is
> certainly paying the same price without much complaining. Or, and this
> is something I've been thinking since, sunlight may be the dumping of
> waste heat. A little more on thermodynamics below.
>
> >I'd expect an advanced computer to notice if some external force
> >started to muc[k] around with its innards, and to do something about it.
>
> Sure, "route around it," in John Gilmore's immortal words. "To see
> the internet in a grain of sand..."
>
> >So if the world around us is an advanced computer, it knows about us
> >and chooses for some reason to allow our activities to continue.
> >Either we are part of this computation, or it works around us.
>
> My assumption is that our activities are so gross and slow that they
> pose no problem. Even we humans know how to do distributed computing,
> redundancy, moving running processes between processors, etc. Anyway,
> I think we would be part of the computation, whether intended
> or noise or bugs. We don't seem much more troublesome than, let's say,
> rainstorms, though. How to compute with dirt seems much harder than,
> "Given I can compute with dirt, what if it gets up and walks?"
>
> >How much physics do you know Steve?
>
> "...Clever people may learn as much as they wish of the results of
> science--still one will always notice in their conversation, and
> expecially in their hypotheses, that they lack the scientific
> spirit; they do not have that instinctive mistrust of the
> aberrations of thought which through long training are deeply
> rooted in the soul of every scientific person. They are content
> to find any hypothesis at all concerning some matter; then they
> are all fire and flame for it and think that is enough... If
> something is unexplained, they grow hot over the first notion
> that comes into their heads and looks like an explanation..."
> --Neitzsche
>
> Say, college freshman level, polluted by popular accounts. Including
> doing my best to understand things like thermodynamics, information
> theory, and reversable and quantum computers.
>
> >I'm not sure you realize how very
> >much we do know about all that information streaming around us.
>
> Well, not enough, but tell me the fastest-reproducing human cell and
> I can compare it to a writable CD-ROM drive...
>
> >We
> >know which systems are exchanging bits with each other, and how fast,
> >and where this arrangement changes, etc.
>
> Wow, do we? How does it compare to the computing cost of *simulating*
> events at the quantum level, or even at the classical-physics level of,
> say, folding proteins? I know no single number completes the picture--
> my point is, it's the *amount* of interaction at various scales that's
> interesting, and I was under the impression that our computers have many
> orders of magnitude to go before we even start to dent that. Plus, our
> computers are a pretty small fraction of the mass of the solar system.
>
> > We also know a lot about
> >designing computers, carefully arranging the routes and speeds of bit
> >exchanges.
>
> Whoa. Computers I know. It is 1996 and almost all computers have single
> processors with clocked logic. One thing we know is that neither of
> those design choices are necessary. Sure, we know "a lot," but how much
> do we know about what all computers *must* look like, under all design
> constraints--especially the dirt constraint?
>
> > And these two really look nothing alike! We can see
> >nature's circuit diagram, even if we don't know what the bits
> >"encode". In particular, we can see the "short" communications
> >channels, where we have no strong reason to expect noise-like bits.
>
> Unless (sorry to repeat) it's strategically necessary to design things
> that way. It might be fun to try to come up with a method for designing
> logic circuits where every signal looked as noisy as, say, a feedback
> shift register. By the way, it's looking natural that's the constraint,
> not looking like noise. Orderly or stereotyped patterns--say, the
> recurrance of atoms in the periodic chart--are part of looking natural.
>
> >To me, the idea that this circuit diagram is actually an
> >optimum design for an advanced computer seems completely crazy.
>
> So I hope I've made my point that you have to look at the driving game
> theory, not just 20th century notions of computer design. If hiding is
an
> absolute constraint, then efficiency is secondary. If the most important
> measure of "optimum" and "advanced" is whether something looks natural,
> dirtlike, then whether it looks "crazy" is also secondary. Heck, almost
> necessary. Just look at the way bits flow through an encryption
algorithm.
> [I will not say, "Yeah, crazy like a fox!" as this would spoil the
> paragraph.]
>
> I think the right point of view is to look at how much information
> is sitting, colliding and moving free at each scale level, and then take
> that as the given and design a computer and software (if the two must be
> distinguished) to make use of it. When you're done you know how much
> computing you can do--and you (the great intergalactic empire) live with
> it. Them's the breaks, we can't compromise security. In computing there
> are often ways of making use of speed *or* storage space, according to
> what's available. Also ways of trading speed for thermodynamic
efficiency.
> I imagine aliens with billion-year patience would have extra slack here.
>
> There are also strange tradeoffs in crypto. Like Chaum's cash protocol
> where you can spend money once anonymously, but if you spend it twice you
> reveal yourself. Imagining much more advanced crypto calls into question
> what we know about the kinds of computing that need to be done, and also
> simple game theory. For instance, imagine it was possible to cause
> something to happen, but not know where it happened. What would that do
> to notions of territory?
>
> The thing I wanted to say about thermodynamics is that calculations of
the
> kind of computing and communicating you can do depend on the background
> noise, or temperature. When trying to figure out how much computing dirt
> or stellar plasma is doing, there is a problem: are those particle
> motions really random? To what extent? If someone could throw off the
> motions they didn't want and replace them with motions they intended,
then
> the effective temperature for the users and outside observers would be
> different. That would change how much computing would seem possible.
>
> (The other cryptocosmology quip: "God is in the least significant bits.")
>
> I don't know whether physics would let this kind of temperature
> difference exist for long, or at what cost. Imagine (metaphorically)
> extremely cold parts moving extremely fast in an extremely well-designed
> machine. Does physics let you keep that up without friction "melting the
> parts" quickly, even with refrigerators? Even with, say, big systems in
> known quantum states (setups too perfect for us to imagine making)?
>
> The sun's light might plausibly be refrigerating the sun. Not so
plausibly
> the planets. Of course sunlight can power planetary refrigerators, but
so
> few of those BTUs are falling on planets. This really makes suns
> look like the place to compute, except that plasma is even more unruly
than
> people (or is it?). Maybe planets are very very slow mass storage, doing
> processing only in order to store and retrieve and refresh. But then
there's
> that nice single crystal of iron that forms the solid core of the
earth...
>
> Planets and suns both seem to have it over interstellar gas and dust
because
> they're compact, but considering what I said about speed/storage
tradeoffs,
> and also all that mysterious free-range sunlight, there could be
something
> going on there.
>
> If we want to think about advanced civilizations, I think we need
> to recognize what a wildcard that "advanced" is.
> Cryptocosmology says They might need to evade probes like science.
> At best we can ask whether computing is possible in "dirt" *as we know
it*.
> If not, the Great Filter has more plausibility.
> If so, there's a giant "OR...NOT" thrown into the picture, with no
> probability assigned at this point, but it would make some questions
> in crypto and game theory more interesting.
>
> --Steve
> P.S., Do you think it would be clearer if I said "Stegocosmology?"
>
> --
> sw@tiac.net
http://www.tiac.net/users/sw
> "See, you think you're on a cruise ship but someone's moving the ocean."
> --Patricia S. Sullivan
>
>
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