Post-Quantum Cryptography — theory, code, news & deep dives
RSA has secured the internet since 1977. Its security rests upon a single assumption — that factoring the product of two large primes is computationally infeasible. For nearly five decades, that assumption has held.
A sufficiently powerful quantum computer running Shor's algorithm dissolves it entirely. The question is no longer whether such a machine will exist, but when.
AfterRSA documents the cryptography being built in its place — the lattice problems, the hardness assumptions, the algorithms and the institutions working to secure what comes next.
Fig. I — Integer lattice Λ(B) with basis vectors b₁, b₂ and shortest vector v*
The Shortest Vector Problem: given a lattice basis, find the shortest non-zero vector. No known algorithm — classical or quantum — solves this efficiently in high dimensions.
Lattice mathematics, reduction proofs, hardness assumptions & paper breakdowns
Python & Rust implementations, liboqs, benchmarks & side-channel analysis
NIST PQC standards, CVEs, industry migration & Q-Day developments
Long-form walkthroughs of Kyber, Dilithium, FALCON & FHE schemes