David Deutsch prefers not to travel. He would rather remain in his study, working. And after listening to the 42-year-old Oxford physicist for a moment, you understand his predilection. How horizons-expanding could any trip be to a man who believes that untold numbers of universes coexist with our own, and that many of them contain a David Deutsch, also happily ensconced in his study?
Deutsch’s lack of intimate contact with the world at large does not preclude his ability to change it profoundly. Ten years ago he conceived of a new type of machine--a quantum computer--which at the time seemed unlikely ever to be built. Now a handful of physicists are actually trying to construct the computer Deutsch envisioned, one whose fundamental components are single atoms or even individual particles of light. If someone succeeds--and it must be said that the technological obstacles are formidable--the very existence of such a ...