The mathematics which we know decides our Quantum future. The whole world knows about Post Quantum Cryptography and the Threat it is trying to solve.

But people misses the moon while focussing on the pointing finger as Bruce Lee told.

The Mathematics is the king here.

Since PQC algorithms from NIST uses neither probability nor Linear Algebra,it uses something called lattice theory.

The core concept is as follows

1. You are in n dimensional space

2.You have lot of dots which are scattered across the n dimensionsal space.

3. You want to find a particular complex point among that dots.

4. From simple geometry we know to reach from one point in space to another point in space vector addition is required.

5.The PQC relies on the fact that if the vectors you are adding is wrong ,you will never reach your target point(the dot)

This concept is used in 

The Shortest Vector Problem(SVP) and Learning With Errors (LWE) problem to generate keys that are hard to break by quantum computers.

Simple enough :D