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Another Breakthrough in Prime Number Theory

Battal Boy writes "From aimath.org: Dan Goldston and his Turkish colleague Yalcin Cem Yildirim have smashed all previous records on the size of small gaps between prime numbers. This work is a major step toward the centuries-old problem of showing that there are infinitely many 'twin primes': prime numbers which differ by 2, such as 11 and 13, 17 and 19, 29 and 31,...I am especially proud of this achievement as Yalcin is a close friend of mine from way back! You may also want to check out the Mercury News Article and Dan Goldston's home page where you can see a photo of Dan's back being slowly but surely broken by two of his children ..." Finding patterns in primes seems to be all the rage.

10 of 241 comments (clear)

  1. Patterns in primes? by TobiasSodergren · · Score: 5, Funny

    Here I thought the patterns-in-primes thing was already solved by Jodie Foster and Matthew McConaughey..

  2. Appreciate the beauty of mathematics, for petesake by neuro.slug · · Score: 5, Insightful

    There's a small joke that goes around in the academic world

    Biologists like to think they are chemists. Chemists like to think they are physicists. Physicists like to think they are mathematicians. And mathematicians like to think they are god.

    Seriously, think of how much of what we learn boils down to our understanding of numbers, systems, and patterns within them. Mathematics, whether you like it or not, is really a beautiful and elegant subject that very few truly understand.

  3. Moo by Chacham · · Score: 5, Funny

    I was waiting for a better time to break this, but I guess now is good to. I have made a groundbreaking discovery in prime numbers.

    No prime numbers can be divided by any number that falls inbetween the number one and the number itself! And, even more exciting, a rule that applies to all prime numbers. All prime numbers can be factored with the number one, but none can be divided by zero.

    I hope none of you had anything important "encrypted" with PGP. Just stick to padless one-time pads for *real* security.

    After I get the National Math Foundation to classify two as an odd number (and it is really odd considering it's the only even prime number) I'll have my third discovery that all prime numbers are odd validated.

    I'd love to post more, but I really must get back to working on my perpetual motion machine. I was so close before, but recently I seem to have lost my bearings. Once I'm done I'll be heralded as the greatest man in the realm of science friction.

  4. Re:Interesting? by LostCluster · · Score: 5, Insightful

    Conversely, having knowledge of more prime numbers also means that new encryption tech can be based on those new theories and enhance privacy. It's kinda a double edge sword...

  5. Re:Moo moo? by saskboy · · Score: 5, Funny

    How exactly does one hold on to frictionless bearings? Do you use [http://www.archive.org/movies/details-db.php?id=2 74]Johnson & Johnson plastic wraps to stick to them?

    http://www.math.utah.edu/~cherk/mathjokes.html
    Several scientists were asked to prove that all odd integers higher than 2 are prime.

    Mathematician: 3 is a prime, 5 is a prime, 7 is a prime, and by induction - every odd integer higher than 2 is a prime.
    Physicist: 3 is a prime, 5 is a prime, 7 is a prime, 9 is an experimental error, 11 is a prime. Just to be sure, try several randomly chosen numbers: 17 is a prime, 23 is a prime...
    Engineer: 3 is a prime, 5 is a prime, 7 is a prime, 9 is an approximation to a prime, 11 is a prime,...
    Programmer (reading the output on the screen): 3 is a prime, 3 is a prime, 3 a is prime, 3 is a prime....
    Biologist: 3 is a prime, 5 is a prime, 7 is a prime, 9 -- results have not arrived yet,...
    Psychologist: 3 is a prime, 5 is a prime, 7 is a prime, 9 is a prime but tries to suppress it,...
    Chemist (or Dan Quayle): What's a prime?
    Politician: "Some numbers are prime.. but the goal is to create a kinder, gentler society where all numbers are prime... "
    Programmer: "Wait a minute, I think I have an algorithm from Knuth on finding prime numbers... just a little bit longer, I've found the last bug... no, that's not it... ya know, I think there may be a compiler bug here - oh, did you want IEEE-998.0334 rounding or not? - was that in the spec? - hold on, I've almost got it - I was up all night working on this program, ya know... now if management would just get me that new workstation tha just came out, I'd be done by now... etc., etc. ..."

    --
    Saskboy's blog is good. 9 out of 10 dentists agree.
  6. Re:Interesting? by jointm1k · · Score: 5, Interesting

    I don't think this will help cracking RSA in anyway. I even believe this will even strengthen the RSA encryption. RSA is based upon the fact that it is very difficult (as in there is no trivial way) to factor a composit number into two primes. And these new theories won't help factorization. Ofcourse, if there is indeed a usufull pattern, it may help to find the primes---that are required for factorization---faster, but the person who uses the RSA-technique can do this too. This will allow the this person to find even bigger primes faster then usuall, so even if the cracker can find possible usufull primes faster, he has to try a whole lot more to facter the composite number. And since trying out a factor to see if the is part of the composite takes much longer time, I only see benefits for the RSA encryption scheme.

    --
    You know it makes sense, a little reminder from jointm1k.
  7. Re:Next step by Yokaze · · Score: 5, Funny

    I'll start: 2 and 3. You'll have to find the next pair.

    --
    "Between strong and weak, between rich and poor [...], it is freedom which oppresses and the law which sets free"
  8. Re:Question of the Day by BabyDave · · Score: 5, Informative

    Short answer: Yes, -3 is prime in the integers.

    Long answer:

    • If a and b are integers, we say that a divides b (and write a|b) if b = a*c for some integer c.
      So 3|6 because 6=3*2, and (-3)|6 because 6 = (-3)*(-2), and so on.
    • An integer p is called prime if for any pair of integers a, b we have that p|(a*b) implies p|a or p|b.
      As an example of this, 48 = 6*8. 3|48, so for 3 to be prime, we would need either 3|6 or 3|8.
      Since 3|6, it passes the test in this case (but remember, the condition has to be true for all pairs of integers.)
    • It turns out that this definition of a "prime number" is the same as the usual one for integers.
    • We know (well, we can show) that 3 is prime. From this we can show that -3 is prime as well,
      since 3|a if and only if (-3)|a (Proof: Slashdot post is too small to contain it ...)
    /me goes back to avoiding revision ...
  9. Boring? by Battal+Boy · · Score: 5, Interesting

    You want boring? Then go and take a look at the PDF papers on this site.

    Are they boring? Yes, exruciatingly and mind numbingly so...
    Did they help us win the Second World War? err...yes

    --

    A cynic is what an idealist calls a realist...
  10. Nitty gritty without karma whoring, poor site /.ed by Anonymous Coward · · Score: 5, Informative

    Small gaps between consecutive primes

    Recent work of D. Goldston and C. Yildirim

    What are the shortest intervals between consecutive prime numbers? The twin prime conjecture, which asserts that p_(n+1) - p_n = 2 infinitely often is one of the oldest problems; it is difficult to trace its origins.

    In the 1960's and 1970's sieve methods developed to the point where the great Chinese mathematician Chen was able to prove that for infinitely many primes p the number p + 2 is either prime or a product of two primes. However the well-known ``parity problem'' in sieve theory prevents further progress.

    What can actually be proven about small gaps between consecutive primes? A restatement of the prime number theorem is that the average size of p_(n+1) - p_n is log(p_n) where p_n denotes the nth prime. A consequence is that

    delta := lim_inf(n -> +inf, (p_(n+1) - p_n) / log(p_n))) = 1

    In 1926, Hardy and Littlewood, using their ``circle method'' proved that the Generalized Riemann Hypothesis (that neither the Riemann zeta-function nor any Dirichlet L-function has a zero with real part larger than 1/2) implies that delta = 2/3. Rankin improved this (still assuming GRH) to delta = 3/5. In 1940 Erdös, using sieve methods, gave the first unconditional proof that delta 1. In 1966 Bombieri and Davenport, using the newly developed theory of the large sieve (in the form of the Bombieri - Vinogradov theorem) in conjunction with the Hardy - Littlewood approach, proved delta = 1/2 unconditionally, and then using the Erdös method they obtained delta = (2 + sqrt(3))/ 8 = 0.46650... . In 1977, Huxley combined the Erdös method and the Hardy - Littlewood, Bombieri - Davenport method to obtain delta = 0.44254. Then, in 1986, Maier used his discovery that certain intervals contain a factor exp(gamma) of more primes than average intervals. Working in these intervals and combining all of the above methods, he proved that delta = 0.2486, which was the best result until now.

    Dan Goldston and Cem Yildirim have a manuscript which advances the theory of small gaps between primes by a quantum leap. First of all, they show that delta = 0. Moreover, they can prove that for infinitely many the inequality

    p_(n+1) - p_n (log(p_n))^(8/9)

    holds.

    Goldston's and Yildirim's approach begins with the methods of Hardy-Littlewood and Bombieri - Davenport. They have discovered an extraordinary way to approximate, on average, sums over prime k-tuples. We believe, after work of Gallagher using the Hardy-Littlewood conjectures for the distribution of prime k-tuples, that the prime numbers in a short interval [N, N + lambda log(N)] are distributed like a Poisson random variable with parameter lambda. Goldston and Yildirim exploit this model in choosing approximations. They ultimately use the theory of orthogonal polynomials to express the optimal approximation in terms of the classical Laguerre polynomials. Hardy and Littlewood could have proven this theorem under the assumption of the Generalized Riemann Hypothesis; the Bombieri - Vinogradov theorem allows for the unconditional treatment.

    This new approach opens the door for much further work. It is clear from the manuscript that the savings of an exponent of 1/9 in the power of log(p_n) is not the best that the method will allow. There are (at least) two possible refinements. One is in the examination of lower order terms that arise in his method. Can they be used to enhance the argument? The other is in the error term Gallagher found in summing the ``singular series'' arising from the Hardy-Littlewood k-tuple conjecture. There is reason to believe that this error term can be improved, possibly using ideas in recent work of Montgomery and Soundararajan (``Beyond Pair - Correlation''.)

    It is not clear just how far this method can be pushed and what other problems might be attacked using his new ideas; at this point we can't rule ou