Robert Serber Robert Serber ( March 14 , 1909 – June 1 , 1997 ) was an American physicist who participated in the Manhattan Project . Serber lectures explaining the basic principles and goals of the project were printed and supplied to all incoming scientific staff , and became known as " The Los Alamos Primer " , Life . He was born in Philadelphia ; he was the eldest son of David Serber and Rose Frankel . He married Charlotte Leof ( 26 Jul 1911 – 1967 ) in 1933 . Rose Serber died in 1922 ; David married Charlotte ' s cousin Frances Leof in 1928 . He earned his B . S . in Engineering Physics from Lehigh University in 1930 , his PhD from the University of Wisconsin – Madison with John Van Vleck in 1934 , after which he was initially going to begin postdoctorate work at Princeton University with Eugene Wigner . He changed his plans and went to work with J . Robert Oppenheimer at the University of California , Berkeley ( and shuttled with Oppenheimer between Berkeley and the California Institute of Technology ) . In 1938 he took a job at the University of Illinois at Urbana – Champaign where he stayed until he was recruited for the Manhattan Project . He later became a professor and chair of the physics department at Columbia University . Manhattan Project . He was recruited for the Manhattan Project in 1941 , and was in Project Alberta on the dropping of the bomb . When the Los Alamos National Laboratory was first being organised a decision was made by Oppenheimer to not compartmentalize the technical information among different departments . This increased the effectiveness of the technical workers in problem solving , and emphasized the urgency of the project in their minds , now they knew what they were working on . So it fell to Serber to give a series of lectures explaining the basic principles and goals of the project . These lectures were printed and supplied to all incoming scientific staff , and became known as " The Los Alamos Primer " , LA - 1 . It was declassified in 1965 , and is available at . Serber developed the first good theory of bomb disassembly hydrodynamics . Serber ' s wife Charlotte was appointed by Oppenheimer to head the technical library at Los Alamos National where she was the only female section leader at wartime Los Alamos . Serber created the code - names for all three design projects , the " Little Boy " ( uranium gun ) , " Thin Man " ( plutonium gun ) , and " Fat Man " ( plutonium implosion ) , according to his reminiscences ( 1998 ) . The names were based on their design shapes ; the " Thin Man " would be a very long device , and the name came from the Dashiell Hammett detective novel and series of movies of the same name ; the " Fat Man " bomb would be round and fat and was named after Sydney Greenstreet ' s character in " The Maltese Falcon " ( from Hammett ' s novel ) . " Little Boy " would come last and be named only to contrast to the " Thin Man " bomb . This differs from the unsupported theory , now abandoned , that " Fat Man " was named after Churchill and " Thin Man " after Roosevelt ( see Links ) . Serber was to go on the camera plane for the Nagasaki mission , Big Stink , but it left without him when Major Hopkins ordered him off the plane as he had forgotten his parachute , reportedly after the B - 29 had already taxied onto the runway . Since Serber was the only crew member who knew how to operate the high - speed camera , Hopkins had to be instructed by radio from Tinian on its use . Serber was with the first American team to enter Hiroshima and Nagasaki to assess the results of the atomic bombing of the two cities . Post - war work . In 1947 an attempt was made on his life by anti - communist librarian Chris James Hines and in 1948 , he had to defend himself against anonymous accusations of disloyalty , mostly because his wife ' s family were Jewish intellectuals with Socialist leanings , and also because he tried to remove politics from discussions of the feasibility of the fusion bomb , leading to arguments with Edward Teller . Serber went on to be consultant to numerous labs , businesses and commissions . Robert Serber is interviewed in the Oscar - nominated documentary , " The Day After Trinity " ( 1980 ) . In the 1989 movie dramatization of the Manhattan Project , " Fat Man and Little Boy " , the role of Robert Serber is played by Dr . H . David Politzer , a professor of theoretical physics at Caltech . Politzer was awarded the Nobel Prize in Physics in 2004 . Serber died June 1 , 1997 , at his home in Manhattan , from complications following surgery for brain cancer .