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UCLA group discovers massive prime number

  1. Sep 29, 2008 #1

    Math Is Hard

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    http://www.msnbc.msn.com/id/26914730/from/ET/
    Go Bruins!
     
  2. jcsd
  3. Sep 29, 2008 #2

    Art

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    What do they use these large prime numbers for? I think I heard one time it was something to do with encryption but if so how does it work? Or is it just for fun?

    Edit - I looked it up and it seems encryption is based on the product of 2 large primes (public key) and the primes themselves (private key) but seeing as how 128 bit encryption already yields 3,835,341,275,459,350,000,000,000,000,000,000,000 different prime numbers which would take a computer 121,617,874,031,562,000 years to crack why bother looking for bigger ones or do primes have other uses?
     
    Last edited by a moderator: Sep 29, 2008
  4. Sep 29, 2008 #3
    Pffft. Chuck norris counted to infinity,.............twice. Don't see him boasting.
     
  5. Sep 29, 2008 #4

    Art

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    I've told Chuck a million times not to exaggerate.
     
  6. Sep 29, 2008 #5
    I found the smallest prime number.
     
  7. Sep 29, 2008 #6

    Art

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    Speaking of which why isn't '1' a prime number any more? It used to be. As all other non-prime numbers except '1' are composite numbers it seems unfair to cast the number '1' out into no-man's land.
     
    Last edited by a moderator: Sep 29, 2008
  8. Sep 29, 2008 #7
    You can define prime number as you wish. However, if you define it so that 1 is prime, then you lose the unique factorization theorem among others.
     
  9. Sep 29, 2008 #8

    Art

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    Hey somebody has to stick up for the little guys :biggrin:

    I think there should be a '1' is prime campaign.
     
    Last edited by a moderator: Sep 29, 2008
  10. Sep 29, 2008 #9

    Borek

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  11. Sep 29, 2008 #10

    Borek

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    I don't have any reference at hand, but I think this information must be outdated. 512 bits key can be breaken in a reasonable time - it was done for the first time not later than in 2000.
     
  12. Sep 29, 2008 #11

    LowlyPion

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    Vista was too slow?
     
  13. Sep 29, 2008 #12

    Ivan Seeking

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    To find very large prime numbers is impressive, but to find one so large that it has mass is really astounding!

    Where did they find it?
     
  14. Sep 29, 2008 #13

    Art

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    :rofl: Maybe it was produced in the LHC.
     
  15. Sep 29, 2008 #14

    Art

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    Drat, Pipped at the post!! I only had 121,617,874,031,561,999 years left in my project to be the first to break it.
     
  16. Sep 29, 2008 #15

    Moonbear

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    :rofl:

    I'm also wondering "why" as well. Is there a useful reason to need to know it, or is it just a weird hobby that math geeks have?
     
  17. Sep 29, 2008 #16
    I read somewhere that a quantum computer was built that factored the number 15. That was my public key.
     
  18. Sep 29, 2008 #17

    Moonbear

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    Oh, that took a LOOOOOOONNNNNGGGGGG time to sink in. GROAN!
     
  19. Sep 29, 2008 #18

    Art

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    Let's face, it with 13 million figures they could tell us anything. It's not as if we're going to go away and check it.
     
  20. Sep 29, 2008 #19
    I think that we should move on from prime numbers to something more interesting.

    Maybe morphing a code with a similar concept to Arnold's Cat Map. That would be fun. (unless they already have done that in which case I just feel stupid).
     
  21. Sep 29, 2008 #20

    Ivan Seeking

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    Yes, but it had the answer before it started the calculation.
     
  22. Sep 29, 2008 #21
    Why would they want to find big primes? Are you kidding? Ask Hillary why he climbs mountains. Ask Phelps why he tries to swim faster. Where is your sense of exploration and discovery?
     
  23. Sep 29, 2008 #22
    what surprises me is that the seti@home copycat prime number searcher people didn't find it first.
     
  24. Sep 30, 2008 #23
    No you don't, every number can be factored by one.

    I don't know why 1 isn't prime, it most definately should be. My guess is that it makes the definition easier to maintain: a prime number is a number that has two distinct factors.

    EDIT: Hmmm... never mind, you lose uniqueness. Very good point =)
     
    Last edited: Sep 30, 2008
  25. Sep 30, 2008 #24
    I'm not a mathematician but here's what I was told. 1 is the only natural number whose reciprocal is also a natural number therefore it is called unity and unity is never prime. Also a number evenly divided by a prime number reveals certain properties of that number, but a number divided by 1 reveals nothing.
     
  26. Sep 30, 2008 #25
    What property does a number being divisible by 7 reveal? Besides the obvious...

    Why can't unity be prime? Its an arbitrary definition. Should 1 not be odd either?
     
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