In case anyone is interested…


Largest Prime Number discovered
A scientist has used his computer to find the largest prime number found so far - written out, it would stretch for 25 kilometres. http://news.bbc.co.uk/2/hi/science/nature/3783149.stm

He didn't actually discover a number, he 'just' showed that this particular number is prime. The gimps project has computers testing to see if numbers of the for 2^P-1 is prime. If P is not prime, then 2^P-1 factors, so they restrict themselves to prime exponents P. All the computers taking part in the project get assigned a prime exponent P, your computer then spends the next few weeks determining if 2^P-1 is prime. How long it takes depends on the speed of your computer and whether or not this number happens to have a factor that can be found very easily. So you don't actually discover a number, just investigate whether it's prime or not.

Though this is the larget known prime number it doesn't mean they've compiled a complete list of all primes up to this point. The gimps is only searching for primes with the special form 2^P-1, which are called Mersenne primes, and doesn't care about the numbers that fall in between. Also, even though it's known there are infinitely many primes, it's not known if there are infinitely many Mersenne primes.

You can take a look at the GIMPS homepage http://www.mersenne.org/prime.htm if you want to join the search or get more info.

So it’s a case of the media reporting a DISCOVERY…because although I’m sure its very interesting with the right background, its not really publicly consumable…;)

It's only mildly interesting with the right background ;). It's a step above when someone with a new gigantic computer or slightly improved algorithm goes and computes the digits of Pi a few billion more places then the last team, but it's still not theoretically interesting, mostly just another demonstration of computational power. Kinda like pulling the proverbial needles from a haystack- if you look long enough, you'll find some, but how interesting is it when you do?

The math and media are funny things. The results that are truly exciting to a mathematician and news worthy are very difficult to appreciate by the layman and often mis-reported by the media.