What Is “Probabilistic” Diophantine Approximation?

We discuss some surprising new developments concerning \(\sqrt{ 2}\), and in general the class of quadratic irrationals. We use \(\sqrt{ 2}\) as the representative for the whole class. These results provide some rigorous evidence for a mysterious general phenomenon that we call the Giant Leap. In a nutshell, it is about the unexpected randomness of explicit sequences (Giant Leap to full-blown randomness). The reader may jump ahead to Sect. 2.5 for a detailed discussion of this issue.