Google last week announced an experiment with post-quantum cryptography in Chrome. A small fraction of connections between Google’s servers and Chrome on the desktop will use a post-quantum key-exchange algorithm in addition to the elliptic-curve key-exchange algorithm already being used. The idea is that large quantum computers — if and when they’re built — might be able to break current security algorithms retroactively, so it would be wise to develop algorithmic proof against such cracking efforts.