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| Fig. 1: Ernest Lawrence and his associate with 27-inch cyclotron at the University of California, Berkeley. (Source: Wikimedia Commons) |
In the early decades of the 20th century, the global physics community was enjoying a period of scientific vibrancy. Marie Curie had won two Nobel prizes (Physics 1903, Chemistry 1911) for her work on radioactive elements, including the discovery of radium and polonium. Ernest Rutherford further investigated the mechanisms of radioactive decay, winning the Nobel Prize (Chemistry 1908) and later used his famous gold foil experiment to demonstrate the existence of the atomic nucleus. Erwin Schrodinger, Werner Heisenberg, Niels Bohr and many other physicists contributed to the establishment of quantum mechanics as the mathematical description of subatomic particles (Nobel Prizes in Physics, 1933, 1932, 1922 respectively). [1] With many of the fundamental underpinnings of atomic physics being developed, the stage was set for further experimental investigations of the nucleus.
In 1928, Ernest Lawrence, a recent Yale PhD graduate in physics, was hired by UC Berkeley as a physics professor to boost their physics department to the heights that their chemistry department was enjoying. The next year, he conceived the idea of a cyclotron, a machine that can accelerate charged particles using an alternating voltage in a spiraled chamber to induce high-speed nuclear collisions. This allowed the collision products to be analyzed to get a more precise understanding of the atomic nucleus. He built a series of cyclotrons on the UC Berkeley campus (see Fig. 1), establishing the famous Radiation Laboratory, or Rad Lab, in 1931 which grew into the now named Lawrence Berkeley National Lab. The Rad Lab, with an extremely powerful cyclotron, became the global center for nuclear physics where technetium, the first artificial element, was first made. Lawrence won the Nobel Prize in Physics in 1939 for his immense contributions to the development of nuclear physics through the invention of the cyclotron. His legacy can be seen through both the eponymous Berkeley, and Lawrence Livermore National Labs. Throughout its history, 14 of 26 discovered transuranium elements were discovered at Berkeley Lab. [2]
A plethora of scientific breakthroughs at Berkeley stemmed directly from the advancements made by Lawrence:
Glenn T. Seaborg, a professor of chemistry at UC Berkeley, used the on-campus cyclotrons established by Lawrence to discover 10 trans-uranium elements including plutonium in 1940 which was later used extensively by the Manhattan Project to build nuclear weapons. Seaborg won the Nobel Prize in Chemistry in 1951 and a continued on to be an advocate against the deleterious effects of nuclear weapons throughout his career. [3]
Melvin Calvin, another professor of chemistry at UC Berkeley, used plentiful Carbon-14, which was discovered at the Rad Lab, to discover the mechanistic pathway of photosynthesis in cells for which he won the Nobel Prize in Chemistry in 1961. [4]
John Lawrence, Ernest Lawrence's younger brother, pioneered the use of radioactive materials in medicine and founded the Donner Laboratory on the Berkeley campus which is now known as the birthplace of nuclear medicine. [5]
UC Berkeley also contributed heavily to the development of nuclear weapons through the Manhattan project. J. Robert Oppenheimer, the director of Los Alamos Laboratory (run by the University of California until 2006), is one of the key figures in the first nuclear weapons that were used on Hiroshima and Nagasaki. His famous quoting of the Bhagavad Gita "I am become death" and his outspoken opposition to nuclear weapons in his later career paints his legacy as fraught with ethical ambiguity. [6]
Edward Teller, another Berkeley physics professor, spearheaded the invention of thermonuclear bombs and worked extensively to promote nuclear weapons as a form of national security. His role in advocating for a U.S. nuclear weapons arsenal has been criticized heavily by the scientific community. [7]
During the Cold War, in 1986, the city of Berkeley was declared a Nuclear Free Zone due to fears of concerns over the dangers of nuclear weapons and energy (although this does not affect research on campus). Currently, a Berkeley city council member is moving to overrule this law to allow the city to efficiently invest in currently disallowed government treasuries. [8]
Berkeley has been at the heart of the understanding of nuclear physics and the application of nuclear phenomena to diverse scientific ventures. These contributions can be quickly summed up in the names of the elements Lawrencium, Livermorium, Seaborgium, Californium and, of course, Berkelium.
© David Koshy. The author warrants that the work is the author's own and that Stanford University provided no input other than typesetting and referencing guidelines. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
[1] D. A. Kleppner, "A Short History of Atomic Physics in the Twentieth Century," Rev. Mod. Phys. 71, S78 (1999).
[2] S. C. Curran, "Prof. E. O. Lawrence," Nature 182, 1058 (1958).
[3] J. L. Heilbron and R. W. Seidel, Lawrence and His Laboratory (University of California Press, 1989).
[4] W. Saxon, "Melvin Calvin Dies at 85; Biochemist Won Nobel Prize," New York Times, 10 Jan 97.
[5] J. E. Williams, "Donner Laboratory: The Birthplace of Nuclear Medicine, " J. Nucl. Med. 40, 16N (1999).
[6] T. Beck, "J. Robert Oppenheimer: Life and Work," Physics 241, Stanford University, Winter 2017.
[7] J. N. Shurkin, "Edward Teller, Father of the Hydrogen Bomb, is Dead at 95," Stanford Report, 24 Sep 03.
[8] A. Emmanuel, "Sometimes Fiscal Urgency Tops Desire to be Nuclear Free, Cities Find," New York Times, 10 Jul 2012
