Alex's Adventures in Numberland - Alex Bellos [69]
‘You have to realize, usually movie-makers repeat their internal state,’ added David sarcastically.
I tell them I thought they might have been flattered by the attention.
‘No, no,’ grinned Gregory.
‘Let me tell you another thing,’ David cut in. ‘Two years ago I came back from France. A couple of days before I left, there was a huge book fair. I stopped at a stand where there was a book that had a detective story on it. It was written by an engineer. It was a murder mystery, you know. A lot of dead bodies, mostly mistress in hotel, and the source that determined everything he did was pi.’
Gregory was smiling from ear to ear and said under his breath: ‘OK, I am not going to read this book, zat’s for sure.’
David carried on: ‘So I talked to the guy. He is a very eucated man.’ He paused, shrugged his shoulders and raised his pitch by an octave: ‘As I say, I bear no responsibility!’
David said that he was taken aback the first time that he saw billboards advertising the Givenchy perfume. ‘All the way down the street was pi…pi…pi…’ He was wailing now: ‘Pi…pi…pi! Do I bear any responsibility?’
Gregory glanced at me and said: ‘For some reason, the general public is fascinated with this stuff. They get kind of the wrong inference.’ There are many professional mathematicians, he said, who study pi. He added wryly: ‘Usually these people are not allowed to see the light of day.’
In the 1950s and 1960s advances in computer technology were reflected in the number of new digits found in pi. By the end of the 1970s the record had been broken nine times and stood at just over a million decimal places. In the 1980s, however, a combination of even faster computers and brand-new algorithms led to a frenetic new era of digit-hunting. Yasumasa Kanada, a young computer scientist at Tokyo University, was first off the block in what became a two-way pi race between Japan and the United States. In 1981 he used an NEC computer to calculate pi to 2 million digits in 137 hours. Three years later he was up to 16 million. William Gosper, a mathematician in California, then nudged into the lead with 17.5 million, before David H. Bailey, at NASA, bettered him with 29 million. In 1986 Kanada overtook them both with 33 million and broke his own record three times in the next two years to reach 201 million with a new machine, the S-820, which did the calculation in just under six hours.
Away from the digit-hunting spotlight, the Chudnovskys were also beavering away on pi. Using a new method of communication called the internet, Gregory connected the computer at his bedside to two IBM supercomputers at different sites in the US. The brothers then devised a program to calculate pi based on the new superfast pi formula they had discovered. They were allowed on to the computers only when no one else was using them, at nights and weekends.
‘It was a great thing,’ remembered Gregory nostalgically. In those days there was no computer capacity to store the numbers that the brothers were calculating. ‘They kept the pi on magnetic tape,’ he said.
‘Mini-tape. And you had to call the guy and ask…’ added David.
‘And say tape number such and such,’ continued Gregory. ‘And sometimes if somebody else is more important your tapes are dismounted in the middle of computation.’ His eyes rolled as if to throw his hands in the air.
Despite the obstacles, the Chudnovskys kept on going, pushing beyond a billion digits. Kanada then nudged ahead of them briefly, before the Chudnovskys retook the lead with 1.13 billion. David and Gregory then decided that if they were serious about calculating pi they needed their own machine.
The Chudnovskian