Wojciech Zurek

A physicist at Los Alamos National Laboratory who, since the early 1980s, has pursued the question of how the classical world emerges from the quantum one.

In 1981–82 he showed how the environment selects a small set of 'pointer states' that survive measurement, and with Wootters (and independently Dieks) he proved in 1982 that an unknown quantum state cannot be copied. His later 'quantum Darwinism' says the states we perceive are those that leave many redundant copies of themselves in the environment.

The no-cloning theorem underlies quantum cryptography's security and shapes every error-correcting scheme in quantum computing. The decoherence programme tells us why classical physics works at all.