<div>Albert Einstein and Max Born were great friends. Their letters span 40 years and two world wars. In them they argue about quantum theory, agree about Beethoven's heavenly violin and piano duets (that they played together when they met) and chat about their families. Equally important, the men commiserate over the tragic plight of European Jewry and discuss what part they should play in the tumultuous politics of the time.<br><br>Fascinating historically, The Born-Einstein Letters is also highly topical: scientists continue to struggle with quantum physics, their role in wartime and the public's misunderstanding. First published by Macmillan in 1971, this book is re-issued, with a substantial new preface by leading US physicists Kip Thorne and Diana Buchwald, as part of 2005's Relativity Centenary celebrations.<br></div>