Wolfgang Ketterle (born 1957), German physicist, in his laboratory. He received the 2001 Nobel Prize for Physics, along with two others, for his work on Bose-Einstein condensates (BECs), the fifth state of matter". These form when atoms are cooled to a fraction of a degree above absolute zero. The atoms then behave as if they were one large atom. Ketterle has used this coherence to form an atom laser, the particle equivalent of a normal (light) laser. BECs could have many uses in nanotechnology and precision measurement. Ketterle is the John A MacArthur professor of physics at the Massachusetts Institute of Technology (MIT), USA. Photographed in 2001."