Victor Frederick " Viki" Weisskopf (September 19, 1908 - April 22, 2002) was an Austrian-born American theoretical physicist. He did postdoctoral work with Werner Heisenberg, Erwin Schrödinger, Wolfgang Pauli and Niels Bohr. During  World War II he was Group Leader of the Theoretical Division of the Manhattan Project at Los Alamos, and later campaigned against the  proliferation of nuclear weapons. 
Weisskopf was born in
Vienna to Jewish parents and earned his doctorate in physics at the University of Göttingen in Germany in 1931. His brilliance in physics led to work with the great physicists exploring the atom, especially Niels Bohr, who mentored Weisskopf at his institute in Copenhagen. By the late 1930s, he realized that, as a Jew, he needed to get out of Europe. Bohr helped him find a position in the United States. 
In the 1930s and 1940s, 'Viki', as everyone called him, made major contributions to the development of quantum theory, especially in the area of
quantum electrodynamics. One of his few regrets was that his insecurity about his mathematical abilities may have cost him a Nobel prize when he did not publish results (which turned out to be correct) about what is now known as the  Lamb shift. 
From 1937 to 1943 he was a Professor of Physics at the University of Rochester.
After World War II, Weisskopf joined the physics faculty at
MIT, ultimately becoming head of the department. At MIT, he encouraged students to ask questions, and, even in undergraduate physics courses, taught his students to think like physicists, not just to learn physics. He was a memorable teacher.
Weisskopf was a co-founder and board member of the
Union of Concerned Scientists. He served as director-general of CERN from 1961 to 1966.     
Weisskopf was awarded the
Max Planck Medal in 1956 and the Prix mondial Cino Del Duca in 1972, the National Medal of Science (1980), the Wolf Prize (1981) and the Public Welfare Medal from the National Academy of Sciences (1991). 
Weisskopf was a member of the National Academy of Sciences. He was president of the
American Physical Society (1960-61) and the  American Academy of Arts and Sciences (1976-1979). 
He was appointed by
Pope Paul VI to the 70-member Pontifical Academy of Sciences in 1975, and in 1981 he led a team of four scientists sent by Pope John Paul II to talk to President Ronald Reagan about the need to prohibit the use of nuclear weapons.
In joint statement
Preserving and Cherishing the Earth with other noted scientists including Carl Sagan it concluded that: The historical record makes clear that religious teaching, example, and leadership are powerfully able to influence personal conduct and commitment...Thus, there is a vital role for religion and science. 
His first wife, Ellen Tvede, died in 1989. He was survived by his second wife Duscha.
Decorations and awards
Human existence is based upon two pillars: Compassion and knowledge. Compassion without knowledge is ineffective; knowledge without compassion is inhuman.
In class one day, speaking to junior physics majors (Spring, 1957): "There is no such thing as a stupid question."
Weisskopf, Victor; Blatt, J. M. (1952). . New York: John Wiley. Theoretical Nuclear Physics
Weisskopf, Victor (1963). Knowledge and Wonder: The Natural World as Man Knows It. New York: Anchor Books/Doubleday & Co. ( Science Study Series S31).
Weisskopf, Victor (1970). Modern Physics from an Elementary Point of View. Geneva: CERN. 
Weisskopf, Victor (1972). . Cambridge, Massachusetts: MIT Press. Physics in the Twentieth Century: Selected Essays
Weisskopf, Victor; Kurt Gottfried (1984). Concepts of Particle Physics, vol. 1. New York: Oxford University Press.
Weisskopf, Victor; Kurt Gottfried (1986). Concepts of Particle Physics, vol. 2. New York: Oxford University Press.
Weisskopf, Victor (1989). The Privilege of Being a Physicist. Essays. New York: W. H. Freeman. Weisskopf, Victor (1991). . New York: Basic Books. The Joy of Insight: Passions of a Physicist
"Weisskopf dies at 93; was protégée of physicist Niels Bohr". MIT News. 24 April 2002 . Retrieved 2015.
"Victor Weisskopf, Group Leader - Los Alamos Theoretical Division". The Manhattan Project Heritage Preservation Association, Inc. 2005 . Retrieved 2015.
"War and Peace in the Nuclear Age; Weapon of Choice, The; Interview with Victor Weisskopf, 1986". openvault.wgbh.org . Retrieved .
Office of the Home Secretary; National Academy of Sciences (1 January 2004). . Vol. 84. National Academies Press. p. 375. Biographical Memoirs ISBN . 978-0-309-08957-9
Gottfried, Kurt; Jackson, J. David (February 2003). "Mozart and Quantum Mechanics: An Appreciation of Victor Weisskopf" (PDF). Physics Today. 56 (2): 43-47. Bibcode: 2003PhT....56b..43G. doi: 10.1063/1.1564348.
Gottfried, Kurt; Jackson, J. David. "Victor Frederick Weisskopf, 1908-2002, A Biographical Memoir" (PDF). p. 16. I might even have shared the Nobel Prize with Lamb
"Who's who in Cern: Victor F. Weisskopf". CERN Courier. 1 (15): 2. Winter 1960.
Hine, Mervyn (January 2003). "Working with Viki at CERN". CERN Courier.
Kummer, Wolfgang (June 2002). "Victor Weisskopf: looking back on a distinguished career". CERN Courier. 42 (5): 28-32.
"Farewell to Professor Weisskopf". CERN Courier. 6 (1): 3-5. January 1966.
"People and things". CERN Courier. 23 (10): 432. December 1983.
"Public Welfare Medal Recipients". National Academy of Sciences. 2015. Archived from the original on 9 August 2013 . Retrieved 2015.
"Past and Present Presidents". American Physical Society. 2015 . Retrieved 2015.
"Academy Presidents". American Academy of Arts & Sciences. 2015 . Retrieved 2015.
Carl Sagan; Hans A. Bethe; S. Chandrasekhar; et al. (January 1990). "Preserving and Cherishing the Earth". Yale Forum on Religion and Ecology . Retrieved 2015.
Chang, Kenneth (2002-04-25). "Victor Weisskopf, a Manhattan Project Physicist, Dies at 93". New York Times . Retrieved .
"Weisskopf wins Oppenheimer Prize". Physics Today. 36 (7): 77. July 1983. doi: 10.1063/1.2915767.
"Reply to a parliamentary question" (PDF). Österreichisches Parlament (in German). Wien. 23 April 2012. p. 1372 . Retrieved 2013.
^ V. Stefan (Editor).
PHYSICS and SOCIETY. Essays in Honor of Victor Frederick Weisskopf by the International Community of Physicists., Forward p. v. ISBN 1-56396-386-8
Medawar, Jean; Pyke, David (2012). Hitler's Gift: The True Story of the Scientists Expelled by the Nazi Regime (Paperback). New York: Arcade Publishing. ISBN . 978-1-61145-709-4 V. Stefan, ed. (1998). PHYSICS and SOCIETY. Essays in Honor of Victor Frederick Weisskopf by the International Community of Physicists. AIP Press. ISBN . 1-56396-386-8
"Weisskopf, Victor Frederick". Encyclopedia.com.
Jackson, J. David; Gottfried, Kurt. "Victor Frederick Weisskopf 1908-2002" (PDF). National Academy of Sciences . Retrieved .
Annotated bibliography for Victor Weisskopf from the Alsos Digital Library for Nuclear Issues
"A Scientist's Odyssey": A Conversation with Victor Weisskopf, April 7, 1988, transcript and RealMedia webcast
Chang, Kenneth (April 25, 2002). "Victor Weisskopf, a Manhattan Project Physicist, Dies at 93". The New York Times . Retrieved 2018.
Oral history interview transcript with Victor Fredrick Weisskopf 10 July 1965, American Institute of Physics, Niels Bohr Library & Archives Victor Weisskopf on INSPIRE-HEP