Re: I find it heartening . .
before an encryption apocalypse is upon us there are already several avenues of investigation open because mathematicians (I assume) 'wasted' their time
Much of the research directly relevant to post-quantum cryptography was done after quantum computing was conceived. After all, we've known Shor's and Grover's algorithms for two decades now.
Lattice-based PQC algorithms like NTRU are of similar vintage. As the article notes, McEliece (one of a family of PQC algorithms based on error-correcting codes) is even older (almost four decades); but it was invented as a cryptosystem, i.e. as a piece of applied mathematics.
It is nice to know that, broadly speaking, cryptography has found applications for number theory and some other once-abstract branches of mathematics - not because there's anything wrong with pure mathematics, but because it's an interesting and unexpected consequence. But it's more true of conventional cryptography than of QC.
Biting the hand that feeds IT
