That’s because certain hard math problems underpin the security of modern encryption. But unlike earlier quantum encryption schemes, which only work for a few special tasks, the new approach can accomplish a much wider range of tasks. “It is not a statement about the real world.”Now, a new paper by two cryptographers has laid out a path to quantum cryptography without those outlandish assumptions. “This paper is saying that if certain other conjectures are true, then quantum cryptography must exist,” Ma said. In the 1980s, researchers proved that cryptography built atop one-way functions would ensure security for many different tasks.