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Paolo glanced at the library again, for a simulation of the process.
Catalytic sites strewn along the sides of each unit trapped the radicals in
place, long enough for new bonds to form between them. Some simple sugars
were incorporated straight into the polymer as they were created; others
were set free to drift in solution for a microsecond or two, until they
were needed. At that level, there were only a few basic chemical tricks
being used ... but molecular evolution must have worked its way up from a
few small autocatalytic fragments, first formed by chance, to this
elaborate system of twenty thousand mutually self-replicating structures.
If the "structural units" had floated free in the ocean as independent
molecules, the "lifeform" they comprised would have been virtually
invisible. By bonding to-gether, though, they became twenty thousand colors
in a giant mosaic.
It was astonishing. Paolo hoped Elena was tapping the library, wherever she
was. A colony of algae would have been more "advanced" but this incredible
primordial creature revealed infinitely more about the possibilities for
the genesis of life. Carbohydrate, here, played every biochemical role:
information carrier, enzyme, energy source, structural material. Nothing
like it could have survived on Earth, once there were organisms capable of
feeding on it and if there were ever intelligent Orpheans, they'd be
unlikely to find any trace of this bizarre ancestor.
Karpal wore a secretive smile.
Paolo said, "What?"
"Wang tiles. The carpets are made out of Wang tiles."
Hermann beat him to the library, again.
"Wang as in twentieth-century flesh mathematician, Hao Wang. Tiles as in
any set of shapes which can cover the plane. Wang tiles are squares with
various shaped edges, which have to fit complementary shapes on adjacent
squares. You can cover the plane with a set of Wang tiles, as long as you
choose the right one every step of the way. Or in the case of the carpets,
grow the right one."
Karpal said, "We should call them Wang's Carpets, in honor of Hao Wang.
After twenty-three hundred years, his mathematics has come to life."
Paolo liked the idea, but he was doubtful. "We may have trouble getting a
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two-thirds majority on that. It's a bit obscure ..."
Hermann laughed. "Who needs a two-thirds majority? If we want to call them
Wang's Carpets, we can call them Wang's Carpets. There are ninety-seven
lan-guages in current use in C-Z half of them invented since the polis was
founded. I don't think we'll be exiled for coining one private name."
Paolo concurred, slightly embarrassed. The truth was, he'd completely
forgotten that Hermann and Karpal weren't actually speaking Modem Roman.
The three of them instructed their exoselves to consider the name adopted:
hence-forth, they'd hear "carpet" as "Wang's Carpet" but if they used the
term with anyone else, the reverse translation would apply.
Paolo sat and drank in the image of the giant alien: the first lifeform
encountered by human or transhuman which was not a biological cousin. The
death, at last, of the possibility that Earth might be unique.
They hadn't refuted the anthrocosmologists yet, though. Not quite. If, as
the ACs claimed, human consciousness was the seed around which all of
space-time had crystallized if the universe was nothing but the simplest
orderly explanation for human thought then there was, strictly speaking, no
need for a single alien to exist, anywhere. But the physics which justified
human existence couldn't help generating a billion other worlds where life
could arise. The ACs would be unmoved by Wang's Carpets; they'd insist that
these creatures were physical, if not biological, cousins merely an
unavoidable by-product of anthropogenic, life-enabling physi-cal laws.
The real test wouldn't come until the diaspora or the Gleisner
robots finally encountered conscious aliens: minds entirely unrelated to
humanity, observing and explaining the universe which human thought had
supposedly built. Most ACs had come right out and declared such a find [ Pobierz całość w formacie PDF ]

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