A new scientific biography of the great Victorian Scottish physicist, and the thought experiment which has taxed the finest minds in physics.

Brian Clegg's has writen many science books, published by Icon and St. Martin's Press. His most recent book for Icon was The Reality Frame. His Dice World and A Brief History of Infinity were both longlisted for the Royal Society Prize for Science Books. He has written for Nature, BBC Focus, Physics World, The Times and The Observer.