How Do You Make An Unbreakable Code? Try Using Quantum Physics
Quantum cryptography is the first method of generating codes that relies on physics rather than mathematics. In quantum key distribution, particles such as photons are used to create a truly random key for deciphering a code, which is then shared between two parties. Because of the strange properties of quantum physics, an eavesdropper trying to steal this key would actually change the key by observing and measuring it. This would also alert the key's rightful owners to the would-be thief's presence.
from Physics Girl
Key Facts In This Video
A one-way function is easy to compute one way, but difficult to reverse. (1:33)
Experts think that with the advent of quantum computing, codes that currently take computers hundreds of years to crack could be solved within minutes. (3:46)
Mathematicians have proven that if you make a truly random numerical key, you can make an unbreakable code called a one-time pad. (5:57)