Lattice based cryptosystems are a viable candidate for post-quantum computing because they will be able to render current number theoretic asymmetric cryptography algorithms obsolete.
Many researchers believe quantum computing will be a practical reality within the next 10 years. Quantum based algorithms will be able to render current number theoretic asymmetric cryptography algorithms obsolete. This means that other algorithms must be discovered, prior to quantum computers becoming a practical reality. Lattice based cryptosystems are a viable candidate for post-quantum computing.