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Loren Booda
Jun14-09, 12:17 AM
To what degree would proving the Riemann hypothesis facilitate the factoring of large composites? In other words, how much would a complete (as opposed to "hit-or-miss") knowledge of primes help to reduce the operations needed to factor large composites?

CRGreathouse
Jun14-09, 01:05 AM
To what degree would proving the Riemann hypothesis facilitate the factoring of large composites? In other words, how much would a complete (as opposed to "hit-or-miss") knowledge of primes help to reduce the operations needed to factor large composites?

Not at all.

It might improve one or two obscure sieving algorithms, though. Maybe the pseudosquare sieve?

Loren Booda
Jun14-09, 02:48 AM
Consider all primes being initially unknown against a complete knowledge of primes. By what parameter does that knowledge reduce the number of operations to factorize composites.

Dragonfall
Jun14-09, 09:56 AM
If memory serves, there are some algorithms which are right now probabilistic, but become deterministic if the generalized RH is true.

EDIT: There we go (http://en.wikipedia.org/wiki/Generalized_Riemann_hypothesis#Consequences_of_GRH ).

CRGreathouse
Jun14-09, 12:20 PM
If memory serves, there are some algorithms which are right now probabilistic, but become deterministic if the generalized RH is true.

EDIT: There we go (http://en.wikipedia.org/wiki/Generalized_Riemann_hypothesis#Consequences_of_GRH ).

Yes, but the question was about the RH not the GRH. And even under the GRH, the article mentions only one factoring algorithm: the quadratic sieve via Shanks-Tonelli. I'm not even sure how Shanks-Tonelli helps the quadratic sieve, since it needs x^2 = a^2 (mod n) and Shanks-Tonelli finds x^2 = b (mod p) for prime p.

Dragonfall
Jun14-09, 06:38 PM
Ya I can't figure it out either. Might have to initiate a discussion the talk page.

Hurkyl
Jun15-09, 10:28 AM
I'm not even sure how Shanks-Tonelli helps the quadratic sieve, since it needs x^2 = a^2 (mod n) and Shanks-Tonelli finds x^2 = b (mod p) for prime p.
One of the steps in the QS requires you to find square roots mod p, doesn't it?

CRGreathouse
Jun15-09, 01:08 PM
One of the steps in the QS requires you to find square roots mod p, doesn't it?

How much time does that take, asymptotically?

Hurkyl
Jun15-09, 11:20 PM
How much time does that take, asymptotically?
Well, you have to solve x²=N (mod p) for every prime p below the smoothness bound. Sounds like a lot.