Cem Yalçın Yıldırım is a Turkish mathematician who specializes in number theory. He obtained his PhD from the University of Toronto in 1990. He is currently a faculty at Boğaziçi University in Istanbul, Turkey.

In a series of 2005 papers (available at ^*), co-authored with Dan Goldston and others, he proves, inter alia, that for any positive number ε there exist primes p and p′ such that the difference between p and p′ is smaller than ε log p.

This has implications for the twin primes conjecture. A non-technical description of the main results can be found at BBC News.

Turkish mathematicians | Living people