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Adam
Dec4-03, 03:03 PM
I first read this story in New Scientist when I was collecting it. Here are some highlights:


Gregory Chaitin, a mathematics researcher at IBM's T. J. Watson Research Center in Yorktown Heights, New York, has shown that mathematicians can't actually prove very much at all. Doing maths, he says, is just a process of discovery like every other branch of science: it's an experimental field where mathematicians stumble upon facts in the same way that zoologists might come across a new species of primate.

The reason for Chaitin's provocative statements is that he has found that the core of mathematics is riddled with holes. Chaitin has shown that there are an infinite number of mathematical facts but, for the most part, they are unrelated to each other and impossible to tie together with unifying theorems. If mathematicians find any connections between these facts, they do so by luck. "Most of mathematics is true for no particular reason," Chaitin says. "Maths is true by accident."

Decades later, in the 1960s, Chaitin took up where Turing left off. Fascinated by Turing's work, he began to investigate the halting problem. He considered all the possible programs that Turing's hypothetical computer could run, and then looked for the probability that a program, chosen at random from among all the possible programs, will halt. The work took him nearly 20 years, but he eventually showed that this "halting probability" turns Turing's question of whether a program halts into a real number, somewhere between 0 and 1.

Chaitin named this number Omega. And he showed that, just as there are no computable instructions for determining in advance whether a computer will halt, there are also no instructions for determining the digits of Omega. Omega is uncomputable.


The article has been reposted here: http://www.you.com.au/news/362.htm and in many other places.

Any comments?

HallsofIvy
Dec5-03, 06:58 AM
I wonder what Chaitin himself thinks of this article.

Unfortunately, newspaper and magazine writers, writing about science or mathematics that they don't understand have a tendency to over-dramatise. Sounds to me like an extension of Goedel's work. And the "omega" of the title is a particular example of a non-computable number. We've known they exist for some time.

selfAdjoint
Dec5-03, 09:17 AM
Chaitin has written stuff himself that is scarcely less lurid than this. He is, um, _very enthusiastic_ about his theory and his place in history.

Guybrush Threepwood
Dec5-03, 09:27 AM
anybody understood the part with Diophantine equations from the article?

motai
Dec5-03, 06:23 PM
A number with no structure... Randomness... sounds saucy, and it reminds me of QM.