What is the connection between mathematics and cryptography?

Personal feeling: these are the two most closely related disciplines. According to certain mathematical laws, the password can be changed every second, and then it can be unlocked. ), and the law is maintained for a period of time, so that opponents can't start. To do something amazing. Mathematics can also be called (cryptography that most people don't have). What is mastered by most people and freely applied (cryptography) is called mathematics (such as+,-,x,? , root sign, logarithm, etc. )