I am currently a MSc student in number theory and considering switching to a phD in cryptography. I would like to use number theory techniques. (i.e. RSA, elliptic curves, etc).
The purpose of all of this is to find a job outside of academia. I would like to find a job in the industry. Here is my worry: in 10-20 years quantum computers will be able to "solve" these problems. Hence, number theory will become useless in cryptography.
Knowing this, will I be able to find a job in the industry in, say, 5 years? My thought is that I will eventually have to adapt but so will everyone else. Will this be a problem for my career?