The physicist Rainer (“Rai”) Weiss, Emeritus Professor at the Massachusetts Institute of Technology (MIT), has just passed away at the age of 92. Weiss’s family emigrated from Nazi Germany in 1933, escaping to Prague, and in 1938 to the USA. His father was a Jewish neurophysiologist from the family that founded the AEG company, and his mother was a Protestant ballet dancer. As a boy and into his youth, Rai developed a very practical interest in electronics, and earned a living building sound systems for his parents’ friends, and for his own friends. At first he studied electrical engineering