If not for the recent wave of Feynmania, Gerard Milburn's new book would probably have been called The Einstein Processor. In a 1935 paper, Einstein and colleagues Boris Podolsky and Nathan Rosen tried to discredit the new theory of quantum mechanics by demonstrating that it led to seemingly impossible results. The famous "EPR" paper showed that if two particles, A and B, are related by some past quantum interaction and an observer measures A's momentum, then B's momentum must instantaneously take on the opposite value-even if A and B are light-years apart. Einstein scorned this result, with its implication of faster-than-light communication, as "spooky action at a distance."

Far from undermining quantum mechanics, however, the EPR paper proved to be science's first glimpse of a bizarre phenomenon: quantum entanglement. Milburn, an Australian theoretical physicist working in the field of "quantum computing," is the first to make entanglement and its real-world significance penetrable for the lay reader.