Julius Robert Oppenheimer (1904-67)

4/22/1904, born, New York City to wealthy Jewish parents, oldest of two sons.
Father, Julius, at 17 immigrated from Hanau GR. in 1898 and worked his way to ownership of a very successful textile-importing firm.
Family, people of dignity, good taste and grooming, non-practicing Jews. Raised children in a very protected, sheltered and cultural environment.


1910-1921, Ethical Culture School, studied math, science, Greek, Latin, French, German.  Became a linguist and showed an interest and aptitude for science at a very early age with many outside pursuits in crystallography and chemistry.  He was an excellent student in all subjects and graduated as valedictorian

1922-25, Harvard U., “He intellectually looted the place”. Majored in chemistry but became exposed to literature, languages and philosophy. Graduated summa cum laude in 3 yrs. Although intellectually advanced he still was an insecure and clumsy adolescent with almost no social skills.
1925-26, Cambridge, U., Cavendish Labs. Found out he had no aptitude for experimental work but did learn of his strengths and interest in theory.
1926-27, U. Gottingen (Born), Ph.D. with distinction, Thesis “On the quantum theory of continuous spectra”.  Published 2 papers.
1927-29, U. Leiden (Ehrenfest), ETH (Pauli), Published 16 papers 1926-29 and developed an international reputation as a theoretical physicist.


1929-43, Accepted joint professorship with U.C. Berkeley and Cal Tech.  At Berkeley, built the greatest school of theoretical physics the U.S. has known.  Became an excellent teacher and learned the value of experimentation so he could successfully direct it.  Although incredibly brilliant, he was caustic, snobbish, arrogant and browbeating and had few professional friends.


10/1941, Became involved in Manhattan Project.
1942 Summer, Assembled group of theorists to throw light on atom bomb design. (Bethe, Teller).
9/1942, Recommends central lab be established.
10/1942, First met Gen. Groves who is impressed.
11/1942, Los Alamos picked as lab site, U.C. picked as prime contractor and operator.
1943-10/45, Directed lab with competence and composure.  His great mobility of mind allowed him to know and understand all activities so as to draw the right conclusions.  He dramatically changed his relationship with people.  Even though intellectually superior, he cared about what everyone was doing and sought ideas and help.
1946, Planned to return to Berkeley but became a public figure in establishing nuclear policy.
1947-66, Director, Institute for Advanced Studies.
1947-52, Chairman, GAC, Atomic Energy Comm.
Opposed the development of the H-Bomb.
4/12-5/6/1954, AEC’s hearings from which his security clearance was denied.  This act ended his public career and influence on national science policy.



1967, Died, throat cancer (63)
Oppenheimer’s name became synonymous with the atomic bomb and also with the dilemma facing scientists when the interest of the nation and their own conscience collide.  He was always an intense person, tall, thin contemplative, probing and in many ways, an enigma.  Even though one of the most brilliant minds of his time, he allowed himself to become associated with “left wing” causes in the 1930s which eventually led to his public downfall.  Many colleagues felt his incredible span of interests detracted from his theoretical work.  Others felt that had he lived longer his massive scientific work at Berkeley would have led to a Nobel Prize.  Those who worked with him felt no one could have been as successful as him in the effort to develop the atomic bomb in such a short time span.

Emilio Gino Segre* (1905-89)

2/1/1905, Born in Tivoli, Rome to wealthy upper middle class family.
Father, Guisseppe, was a prosperous owner of a paper mill.



1911-1922, Early schooling took place in Tivoli and Rome where he demonstrated and interest and aptitude for science math and mechanics.



1922, U. Rome, enrolled as engineering student.  After several years as an excellent student, Fermi and Rassetti personally recruited him into the physics program by taking him to a major European meeting in Como where he met all the major physicists of Europe.

1928, PhD, (Fermi).
1928-29, Italian Army to fulfill military duty.
1929-1936, U. Rome, Assistant–Prof. Corbino.  The first of a small group assembled by Fermi to investigate the nucleus.
1930-31, U. Hamburg (Stern)
1931-32, U. Amsterdam (Zeeman).  Was sent by Fermi to gain experimental experience with two of the greatest experimental physicists.
1932-36, Asst. Prof., participated with Fermi in investigation of radioactive elements and discovering the method of slow neutron bombardment of the nucleus.
1936-38, U. Palermo, Director, Physics Laboratory.
1938, Discovery of Technetium with Perrier.
Spent the summer 1938 in Berkeley working on Technetium, but Mussolini’s anti-Semitic campaign caused him to stay in the U.S.
1938-43, U.C. Berkeley, Research Associate, Radiation Laboratory and later Lecturer in Physics.
Attracted to Berkeley by the Cyclotron.
1939, Discovery of Astatine with Corson & Mackenzie.
3/1941, with Seaborg, Kennedy and Wahl, discovered Element 239 (later named Plutonium) and its fissionability.

1943-46, Berkeley/Los Alamos, Section Leader.  Determined the spontaneous fission rates of U235, which reduced the size of the “Little Boy” bomb so as to make it feasible.
10/1946, Returned to Berkeley, Professor of Physics.



1955, with Chamberlain, Weigand and Ypsilantis, discovered the anti-proton.



1959, Nobel Prize shared with Chamberlain, “Discovery of the Anti-Proton”.


Being trained in Fermi’s multi-disciplinary lab, Segre became not only an accomplished theorists but an outstanding experimentalist, which he pursued throughout his career. He focused on atomic and nuclear physics.  His early work in atomic spectroscopy, studied the Zeeman effect.  With Fermi, his focus was on the nucleus, particularly neutron bombardment.  At U.C. Berkeley his work centered on the cyclotron and the production of trans-uranium elements.  He made a major contribution to the atomic bomb effort by accurately identifying the spontaneous fission of U235.  It is interesting to note how much more productive experimentalists are throughout their career. Segre’s Nobel work occurred at age 50.  While theorists work by themselves, experimentalists seem to work in teams.



1989, Died (84)