I’ve always admired the science fiction of Jack Vance; he has a baroque yet precise prose style, like steel draped in velvet. But one of his novels, _The Killing Machine_, rests on a premise that I always thought was a little silly. The money of Vance’s future society cannot be forged; fake-detecting machines can invariably tell the real banknotes from the bogus. The hero of the novel finds out why – the paper of real banknotes is crimped in a manner that is spaced “in terms of the square root of the first eleven primes” – and he’s able to print himself up a small fortune’s worth of undetectable forgeries. This sort of legerdemain always seemed rather implausible to me.
No longer. Now I discover via “Ed Felten”:http://www.freedom-to-tinker.com/archives/000497.html that
bq. some color copiers look for a special pattern of five circles (usually yellow or orange in color), and refuse to make high-res copies of documents containing them. Sure enough, the circles are common on paper money. (On the new U.S. $20 bills, they’re the zeroes in the little yellow “20”s that pepper the background on the back side of the bill.) Markus called the special five-dot pattern the “constellation EURion” because he first spotted it on Euro notes.
{ 7 comments }
mike d 01.15.04 at 8:11 pm
it’s not just copiers… the latest version of Adobe Photoshop is supposed to be able to do this, but there’s an easy workaround…
Sigivald 01.15.04 at 11:19 pm
Computers are, after all, very good at detecting the existence of a pre-known pattern in a pre-known medium. Not good at all, of course, in detecting patterns whose existence is not known in advance, but very good, with the right software, at the converse.
bob mcmanus 01.16.04 at 1:45 am
Jack Vance was just weird, his content as well as his style was unique,like Sabatini filtered thru a Martian. But I love him. Science fiction a very accepting field, as long as you don’t expect to make any money.
TomD 01.16.04 at 11:08 am
It’s very easy to spot once you know about it: a hacker would probably have rather little trouble identifying and removing the relevant bits of code in whatever program was refusing to copy.
Not quite up to the level of the square roots of the first eleven prine numbers (although I would imagine that if the notes were ‘crimped’ they could easily get out of shape…).
Patrick Nielsen Hayden 01.16.04 at 2:30 pm
“Jack Vance was just weird”…
Present tense, not past. He’s still alive, and just delivered his next novel, Lurulu, to his publisher.
maurinsky 01.16.04 at 2:38 pm
Most of our pets are named after characters from Jack Vance’s fantasy books – our cats are Casmir and Madouc, and our dog is Cugel. Our non Jack Vance pets are a fish called Fiona and 2 hermit crabs called Merry and Pippin.
Sadly, that is all I can contribute to this discussion, because I’ve never read any of his Sci-fi books.
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