# Status of current research in Sieve Theory

I have done a course in Sieve Theory from the notes of Prof. Rudnick. Before this, I did 2 courses in Number Theory from the 2 volumes of Apostol.

I don't have any guidance by professor as I am living in a very poor country in Europe and I study mathematics in spare time though I am serious about it.

While I was searching for papers in Sieve theory( I wanted to read more papers in Sieve Theory), there are not many people working in Sieve Theory. Comparatively, much more work is been going in L-functions ( Low lying zeroes, twists, Multiple L-functions and so on) and Modular forms. Can you please let me know why? Has research in Sieve Theory attained saturation?

Kindly let me know!

Thanks!

• Plenty of people are working in sieve theory. For one prominent example, look no further than recent breakthroughs on primes in bounded intervals (or, really, pretty much any result on prime gaps). It very well may be true that more people focus on other aspects of analytic number theory like analytic properties of L-functions, but sieve theory is nowhere near "saturated". Jul 16 at 16:47
• To learn about sieve theory and the problems that are relevant to it, read Opera de Cribro by John Friedlander and Henryk Iwaniec. Jul 19 at 11:35

Sieve theory is not saturated. It is alive and thriving. The ICM just awarded the Fields medal to James Maynard in no small part due to his work in sieve theory (see here and here). Because of the natural role of multiplicative structure in sieve theory, there are lots of fascinating and important results in the theory of $$L$$-functions and modular forms that rely decisively on sieve theory. In these instances, it is usually the flexibility of sieve methods that ends up being the key to success. On the other hand, there are lots of things that one can study about $$L$$-functions and modular forms that have nothing to do with sieve theory.
Here are some examples where sieve theory, $$L$$-functions, modular forms, and other ideas combine, resulting in truly splendid results. This list is far from exhaustive.
• Radziwill and Soundararajan's work on moments of $$L$$-functions associated to quadratic twists of elliptic curves (where they, in essence, prove a robust "Brun-Hooley type" sieve for $$L$$-functions);