You can't have your quantum cake and eat it

DAVID BOHM’s last great work on quantum theory – the definitive account of his ideas – The Undivided Universe, written with B. J. Hiley, is now available in paperback from Routledge (pp 297, £12.99). Experiments in the 198Os showed that you cannot have both “reality” and “locality” in the quantum world. Either communication occurs faster than light, and particles are real, or communication faster than light is forbidden, and we are stuck with collapsing wave functions and half-dead cats. Bohm argued for 40 years that the world is nonlocal, and recent work, such as that by John Cramer in Seattle, leans the same way. An important, forward-looking book – but, it must be said, highly technical in parts.