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-   -   Any inaccurate information in M40 news reports? (https://www.mersenneforum.org/showthread.php?t=1603)

TauCeti 2003-12-08 15:42

If some of you are interested in science fiction novels, i can recommend [I]Souls in the Great Machine[/I] from Sean McMullen.

In this novel, a huge calculator is build with thousands of humans performing the primitive operations. Even an error correction concept is included.

only_human 2003-12-08 19:16

[QUOTE][i]Originally posted by Dresdenboy [/i]
[B]I didn't like the impression which german news magazine Focus gave to their readers ([url]http://news.focus.msn.de/G/GN/gn.htm?snr=127350&streamsnr=241&streamsnr=241[/url]).

Unfortunately the article didn't show clearly, that everyone, who's interested, could devote their idle CPU time to GIMPS by simply installing a client although they say, that everyone could join. [/B][/QUOTE]

Another way that readers might get a mistaken impression follows from the use some articles are making of this factoid found within the Mersenne.org press release title: "220996011-1 is Found with 25,000 Years of Computer Time"

For example the BBC News UK Edition article ([URL=http://news.bbc.co.uk/1/hi/sci/tech/3256822.stm]Prime position for large number[/URL]) says that GIMPS [I]spent[/I] 25,000 years of computer time to find this prime. This seems to me to imply that the time used was devoted in lieu of other activities. A minor quibble, especially since (although not mentioning idle time) the article mentions elsewhere that the software doesn't affect computer use for other activities at the same time.

Dresdenboy 2003-12-08 19:30

Do these 25000 years mean P90 time? It would be difficult to calculate the actually spent calculation time of todays computers because of the many differences.


only_human 2003-12-08 20:06

Actually it would have been better for me to say the press release hosted on mersenne.org. Described thus:
Scott Kurowski, who runs the server that controls GIMPS' massive CPU power, wrote this [URL=http://www.mersenne.org/20996011.htm]press release[/URL].
The title is:
Mersenne Project Discovers Largest Known Prime Number
on World-Wide Volunteer Computer Grid
220996011-1 is Found with 25,000 Years of Computer Time

I think it must be using P90 years but don't really know.

only_human 2003-12-09 08:05

Anyway, I hope no one has taken this thread I started badly. I find it amazing how well the articles I have read cover so many points about the numbers, mathematics, people, machines, software and organizations involved. That is a lot of ground to touch upon. The care taken in preparing for the announcement of this discovery has obviously paid off.

jinydu 2003-12-10 13:38

[url]http://www.gridcomputingplanet.com/news/article.php/3287041[/url]

New Mersenne Prime Found

Michael Shafer, a 26-year-old volunteer in the Mersenne.org research project called the Great Internet Mersenne Prime Search, has discovered the largest known prime number.

Shafer used a Michigan State University lab PC and free software as part of an international Grid of 211,000 networked computers.

The new number, expressed as 2 to the 20,996,011th power minus 1, has 6,320,430 decimal digits and was discovered Nov. 17. It is more than two million digits larger than the previous largest known prime number, and belongs to a special class of rare prime numbers called Mersenne primes. The discovery is the 40th known Mersenne prime, named after Marin Mersenne, a 17th century French monk who first studied the numbers.

The new prime is 63% of the qualifying size for the $100,000 Electronic Frontier Foundation award for the first 10-million-digit prime, also being sought by the project's volunteers. In May 2000, a previous participant won the foundation's $50,000 award for discovering the first million-digit prime.

The new prime was independently verified by Guillermo Ballester Valor of Granada, Spain using twelve days of time on a 1.4GHz quad Itanium II server at the HP Test Drive center, and by Ernst Mayer of Cupertino, Calif., using three weeks of time on a 1 GHz HP Alpha workstation. The discovery is the sixth record prime found by the GIMPS project, and the fourth discovered using distributed computing software from Entropia Inc.



"The discovery is the 40th known Mersenne prime, named after Marin Mersenne, a 17th century French monk who first studied the numbers."

I don't think Mersenne was the first to study primes of the form (2^p)-1.

"The new prime is 63% of the qualifying size for the $100,000 Electronic Frontier Foundation award for the first 10-million-digit prime, also being sought by the project's volunteers."

I may seem a little picky here but, this seems to give the impression that a prime big enough to win the $100K is 1.582 (1/0.63) times larger than M(40). In fact, a ten million digit prime would be about (10^3679570.9) times larger than M(40). That is, M10million digits >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>M(40).

ewmayer 2003-12-10 16:46

When we talk about the sizes of large primes we always use the number of digits (or for the Mersennes, the exponent, which is equivalent), i.e. we talk about the prime in the logarithmic sense. So it's not inaccurate to say M#40 is 63% of the size needed for the 10Mdigit prize.

lycorn 2003-12-10 18:21

Re: Any inaccurate information in M40 news reports?
 
[QUOTE][i]Originally posted by only_human [/i]
[B]

What other mistakes are out there? [/B][/QUOTE]

On a portuguese online newspaper there was a nice article about the finding, except that it was stated that Mersenne primes are of the form 2*p-1:shock: :sick: Dooohhh!...

eu-Robert 2003-12-10 22:19

Yeah, lycorn, I know, I've sent them an e-mail about that error last Sunday, asking the webmaster to change the HTML code to 2<sup>20996011</sup>-1, and 2<sup>p</sup>-1, but so far, [i]nada[/i]... :sad:

I've sent them that e-mail again, rephrased, repeating the request, just now.


The same problem (no superscript for the exponent) occurs in several other online articles. Perhaps they were asleep during math classes? :sleep:

eu-Robert 2003-12-11 18:12

Received a friendly reply a few hours ago, that they've now corrected the article. [i]Sím![/i]

[url]http://www.diariodigital.pt/news.asp?section_id=60&id_news=72674[/url]

only_human 2003-12-11 18:35

While I have not sent any corrections to any of these papers, I have sent corrections to two math related web sites.
One was for a minor spelling error. It was quickly fixed and I received two thank you emails;
The other was for a minor formatting error of 2[sup]n-1[/sup] when 2[sup]n[/sup]-1 was intended. I received a thank you for that and it was also fixed.

I felt very encouraged that they saw and personally responded to my emails especially since I have never contacted either of them before. I feel sure they must be receiving torrents of posts about misperceived problems and others offering quasimathematical [i]proofs[/i] of various things.


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