Team Solves Mammoth, Century-Old Math Problem Scientists have solved one of the toughest problems in mathematics, performing a calculation to figure out the symmetry of a complicated 248-dimensional object known as the Lie group E8. The solution is so large that it would take days to download over a standard Internet connection.

## Team Solves Mammoth, Century-Old Math Problem

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Team Solves Mammoth, Century-Old Math Problem

# < Team Solves Mammoth, Century-Old Math Problem

## Team Solves Mammoth, Century-Old Math Problem

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MICHELE NORRIS, host:

Here's an equation that'll never make it to the SATs: a 120-year-old math problem divided by 18 scientists plus four years equals an answer so large that if written in the tiniest of print, it would cover a piece of paper the size of Manhattan.

ROBERT SIEGEL, host:

That's right. We even read that if you passed up on the Gotham-sized hard copy, the answer is so gigantic it would take days to download to your computer, probably months if you're still on dial-up.

NORRIS: And explaining the problem to non-mathematicians could take just as long. It has to do with an untangling of the inner workings of a complicated object known as E8.

Dr. BRIAN CONREY (Director, American Institute of Mathematics): It's a giant, mysterious, very symmetrical object, maybe the most symmetrical object in the whole mathematical universe.

SIEGEL: Brian Conrey is trying to simplify it for us. He's the director of the American Institute of Mathematics in Palo Alto, California. They funded the research to figure out how the shape known as E8 works.

Dr. CONREY: It has 248 dimensions, which sounds pretty frightening at first. But really, you should think of dimensions as being degrees of freedom. So if you were studying the weather, you might look at, you know, temperature and humidity and pressure and wind speed and all those things. And pretty soon, you might have a list of 10 different attributes you were looking at. Well, we would call that 10-dimensional.

So if you just think of the 248 as being kind of 248 variables, then you're off to a good start.

NORRIS: Got it: symmetrical object, 248 variables. And nobody really understood E8 ever since it was first described by a Norwegian mathematician in 1887.

SIEGEL: Conrey says modern mathematicians are thrilled that his institute has cracked E8, and we take his word for it. He says they expect the solution will propel future advances in science and technology, though he admits he's not sure how.

Dr. CONREY: I don't know that it's going to make a smaller hard drive or make your cell phone have a clearer signal or that it's going to show up in electronic gadget in Frye's Electronics anytime soon, but I wouldn't be surprised if it did at some point.

NORRIS: Brian Conrey says his institute is on to its next big challenge, something called the Riemann hypothesis. It has to do with prime numbers, and it's been a mystery since 1854.