Val Logsdon Fitch

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Val Logsdon Fitch
Val Fitch.jpg
Born(1923-03-10)March 10, 1923
DiedFebruary 5, 2015(2015-02-05) (aged 91)
Alma mater Columbia
McGill University
Known forDiscovery of CP-violation
Awards E. O. Lawrence Award (1968)
John Price Wetherill Medal (1976)
Nobel Prize in Physics (1980)
National Medal of Science (1993)
Scientific career
Fields Particle physics
Thesis Studies of X-rays from Mu-Mesonic Atoms (1954)
Doctoral advisor James Rainwater

Val Logsdon Fitch (March 10, 1923 – February 5, 2015) was an American nuclear physicist who, with co-researcher James Cronin, was awarded the 1980 Nobel Prize in Physics for a 1964 experiment using the Alternating Gradient Synchrotron at Brookhaven National Laboratory that proved that certain subatomic reactions do not adhere to fundamental symmetry principles. Specifically, they proved, by examining the decay of K-mesons, that a reaction run in reverse does not retrace the path of the original reaction, which showed that the reactions of subatomic particles are not indifferent to time. Thus the phenomenon of CP violation was discovered. This demolished the faith that physicists had that natural laws were governed by symmetry.

Nuclear physics field of physics that deals with the structure and behavior of atomic nuclei

Nuclear physics is the field of physics that studies atomic nuclei and their constituents and interactions. Other forms of nuclear matter are also studied. Nuclear physics should not be confused with atomic physics, which studies the atom as a whole, including its electrons.

Nobel Prize in Physics One of the five Nobel Prizes established in 1895 by Alfred Nobel

The Nobel Prize in Physics is a yearly award given by the Royal Swedish Academy of Sciences for those who have made the most outstanding contributions for humankind in the field of physics. It is one of the five Nobel Prizes established by the will of Alfred Nobel in 1895 and awarded since 1901; the others being the Nobel Prize in Chemistry, Nobel Prize in Literature, Nobel Peace Prize, and Nobel Prize in Physiology or Medicine.

Alternating Gradient Synchrotron

The Alternating Gradient Synchrotron (AGS) is a particle accelerator located at the Brookhaven National Laboratory in Long Island, New York, United States.


Born on a cattle ranch near Merriman, Nebraska, Fitch was drafted into the U.S. Army during World War II, and worked on the Manhattan Project at the Los Alamos Laboratory in New Mexico. He later graduated from McGill University, and completed his Ph.D. in physics in 1954 at Columbia University. He was a member of the faculty at Princeton University from 1954 until his retirement in 2005.

Merriman, Nebraska Village in Nebraska, United States

Merriman is a village in Cherry County, Nebraska, United States. The population was 128 at the 2010 census.

Manhattan Project research and development project that produced the first atomic bombs

The Manhattan Project was a research and development undertaking during World War II that produced the first nuclear weapons. It was led by the United States with the support of the United Kingdom and Canada. From 1942 to 1946, the project was under the direction of Major General Leslie Groves of the U.S. Army Corps of Engineers. Nuclear physicist Robert Oppenheimer was the director of the Los Alamos Laboratory that designed the actual bombs. The Army component of the project was designated the Manhattan District; Manhattan gradually superseded the official codename, Development of Substitute Materials, for the entire project. Along the way, the project absorbed its earlier British counterpart, Tube Alloys. The Manhattan Project began modestly in 1939, but grew to employ more than 130,000 people and cost nearly US$2 billion. Over 90% of the cost was for building factories and to produce fissile material, with less than 10% for development and production of the weapons. Research and production took place at more than 30 sites across the United States, the United Kingdom, and Canada.

New Mexico State of the United States of America

New Mexico is a state in the Southwestern region of the United States of America; its capital and cultural center is Santa Fe, which was founded in 1610 as capital of Nuevo México, while its largest city is Albuquerque with its accompanying metropolitan area. It is one of the Mountain States and shares the Four Corners region with Utah, Colorado, and Arizona; its other neighboring states are Oklahoma to the northeast, Texas to the east-southeast, and the Mexican states of Chihuahua to the south and Sonora to the southwest. With a population around two million, New Mexico is the 36th state by population. With a total area of 121,592 sq mi (314,920 km2), it is the fifth-largest and sixth-least densely populated of the 50 states. Due to their geographic locations, northern and eastern New Mexico exhibit a colder, alpine climate, while western and southern New Mexico exhibit a warmer, arid climate.

Early life

Val Logsdon Fitch was born on a cattle ranch near Merriman, Nebraska, on March 10, 1923, the youngest of three children of Fred Fitch, a cattle rancher, and his wife Frances née Logsdon, a school teacher. [1] He had an older brother and sister. [2] The family farm was about 4 square miles (10 km2) in size, and was about 40 miles (64 km) from the site of the Wounded Knee Massacre. [1] The ranch was a small one; his father specialized in raising breeding stock. [3] Soon after his birth, his father was badly injured in a horse riding accident and could no longer work on his ranch, so the family moved to the nearby town of Gordon, Nebraska, where his father entered the insurance business. [1] It was here that he attended school, [1] graduating from Gordon High School in 1940 as valedictorian. [4] [5]

Wounded Knee Massacre massacre

The Wounded Knee Massacre occurred on December 29, 1890, near Wounded Knee Creek on the Lakota Pine Ridge Indian Reservation in the U.S. state of South Dakota.

Gordon, Nebraska City in Nebraska, United States

Gordon is a city in Sheridan County in the state of Nebraska, in the Great Plains region of the United States. Its population was 1,612 at the 2010 census.

Valedictorian is an academic title of success used in the United States, Canada, Central America, Singapore, and the Philippines for the student who delivers the closing or farewell statement at a graduation ceremony. The chosen valedictorian is often the student with the highest ranking among their graduating class. The term is an Anglicised derivation of the Latin vale dicere, historically rooted in the valedictorian's traditional role as the final speaker at the graduation ceremony before the students receive their diplomas. The valedictory address generally is considered a final farewell to classmates, before they disperse to pursue their individual paths after graduating.

Manhattan Project

Fitch attended Chadron State College for three years, then transferred to Northwestern University; but this was during World War II, and his studies were interrupted by being drafted into the U.S. Army in 1943. After he had completed basic training, the Army sent him to Carnegie Institute of Technology for training under the Army Specialized Training Program. [2] Under this program, some 200,000 soldiers attended colleges for intensive courses. Fitch was in the program for less than a year before the manpower requirements of the war became too great, and the Army terminated the program. Most of the soldiers in the ASTP were posted to combat units, but Fitch was one of a hundred or so ASTP soldiers who joined the Special Engineer Detachment (SED), which provided much-needed technicians to the Manhattan Project. [2] [6] [7]

Chadron State College

Chadron State College is a four-year public college located in Chadron, Nebraska, in the northern part of the Nebraska Panhandle. It is one of three public colleges in the Nebraska State College System.

Northwestern University Private research university in Illinois, United States

Northwestern University (NU) is a private research university based in Evanston, Illinois, United States, with other campuses located in Chicago and Doha, Qatar, and academic programs and facilities in Miami, Florida; Washington, D.C.; and San Francisco, California. Along with its undergraduate programs, Northwestern is known for its Kellogg School of Management, Pritzker School of Law, Feinberg School of Medicine, Bienen School of Music, Medill School of Journalism, and McCormick School of Engineering and Applied Science.

Army Specialized Training Program

The Army Specialized Training Program (ASTP) was a military training program instituted by the United States Army during World War II to meet wartime demands both for junior officers and soldiers with technical skills. Conducted at 227 American universities, it offered training in such fields as engineering, foreign languages, and medicine.

The Army sent Fitch to the Manhattan Project's Los Alamos Laboratory in New Mexico. By mid-1944, about a third of the technicians at Los Alamos were from the SED. While there, he met many of the greats of physics including Niels Bohr, James Chadwick, Enrico Fermi, Isidor Isaac Rabi, Bruno Rossi, Emilio Segrè, Edward Teller and Richard C. Tolman, in some cases attending courses on physics taught by them. He worked in the group headed by Ernest Titterton, a member of the British Mission, and became well-acquainted with the techniques of experimental physics. He participated in the drop testing of mock atomic bombs that was conducted at Wendover Army Air Field and the Salton Sea Naval Auxiliary Air Station, and worked at the Trinity site, where he witnessed the Trinity nuclear test on July 16, 1945. He was discharged from the Army in 1946, but continued to work at Los Alamos as a civilian for another year in order to earn some money. He would briefly return to Los Alamos in summer 1948. [1] [2] [7]

Niels Bohr Danish physicist

Niels Henrik David Bohr was a Danish physicist who made foundational contributions to understanding atomic structure and quantum theory, for which he received the Nobel Prize in Physics in 1922. Bohr was also a philosopher and a promoter of scientific research.

James Chadwick English physicist

Sir James Chadwick, was a British physicist who was awarded the 1935 Nobel Prize in Physics for his discovery of the neutron in 1932. In 1941, he wrote the final draft of the MAUD Report, which inspired the U.S. government to begin serious atomic bomb research efforts. He was the head of the British team that worked on the Manhattan Project during the Second World War. He was knighted in Britain in 1945 for his achievements in physics.

Enrico Fermi Nuclear physicist

Enrico Fermi was an Italian and naturalized-American physicist and the creator of the world's first nuclear reactor, the Chicago Pile-1. He has been called the "architect of the nuclear age" and the "architect of the atomic bomb". He was one of very few physicists to excel in both theoretical physics and experimental physics. Fermi held several patents related to the use of nuclear power, and was awarded the 1938 Nobel Prize in Physics for his work on induced radioactivity by neutron bombardment and for the discovery of transuranium elements. He made significant contributions to the development of statistical mechanics, quantum theory, and nuclear and particle physics.

Academic career

His wartime experiences led Fitch to decide to become a physicist. Robert Bacher, the head of the physics division at Los Alamos, offered him a graduate assistantship at Cornell University, but first he needed to complete his undergraduate degree. Rather than return to Northwestern or Carnegie Mellon, he elected to enter McGill University, which Titterton had recommended. Fitch graduated from McGill with a bachelor's degree in electrical engineering in 1948. On the advice of Jerry Kellogg, who had been a student of Rabi's at Columbia University, and was a division head at the Los Alamos, Fitch decided to pursue his doctoral studies at Columbia. Kellogg wrote him a letter of introduction to Rabi. James Rainwater became his academic supervisor. Rainwater gave him a paper by John Wheeler concerning mu-mesic atoms, atoms in which an electron is replaced by a muon. These had never been observed; they were completely theoretical and there was no evidence that they existed, but it made a good thesis topic. [1] [2]

Robert Bacher American nuclear physicist

Robert Fox Bacher was an American nuclear physicist and one of the leaders of the Manhattan Project. Born in Loudonville, Ohio, Bacher obtained his undergraduate degree and doctorate from the University of Michigan, writing his 1930 doctoral thesis under the supervision of Samuel Goudsmit on the Zeeman effect of the hyperfine structure of atomic levels. After graduate work at the California Institute of Technology (Caltech) and the Massachusetts Institute of Technology (MIT), he accepted a job at Columbia University. In 1935 he accepted an offer from Hans Bethe to work with him at Cornell University in Ithaca, New York, It was there that Bacher collaborated with Bethe on his book Nuclear Physics. A: Stationary States of Nuclei (1936), the first of three books that would become known as the "Bethe Bible".

Cornell University private university in Ithaca (New York, US)

Cornell University is a private and statutory Ivy League research university in Ithaca, New York. Founded in 1865 by Ezra Cornell and Andrew Dickson White, the university was intended to teach and make contributions in all fields of knowledge—from the classics to the sciences, and from the theoretical to the applied. These ideals, unconventional for the time, are captured in Cornell's founding principle, a popular 1868 Ezra Cornell quotation: "I would found an institution where any person can find instruction in any study."

McGill University English-language university in Montreal, Quebec

McGill University is a public research university in Montreal, Quebec, Canada. It was established in 1821 by royal charter, granted by King George IV. The university bears the name of James McGill, a Montreal merchant originally from Scotland whose bequest in 1813 formed the university's precursor, McGill College.

Fitch designed and built an experiment to measure the gamma rays emitted from mu-mesic atoms. As it turned out, this was a good time to search for them. Columbia had recently commissioned a cyclotron at the Nevis Laboratories that could produce muons; Robert Hofstadter had developed the thallium-activated sodium iodide gamma ray detector; and wartime advances in electronics yielded advances in components such as new phototubes needed to bring it all together. Initially nothing was found, but Rainwater suggested expanding the search beyond the energy range predicted by Wheeler on the basis of the then-accepted size of the radius of the atomic nucleus as around 1.4 × 10−15 m. When this was done, they found what they had been looking for, discovering in the process that the nucleus was closer to 1.2 × 10−15 m. [1] [2] He completed his Ph.D. in 1954, writing his thesis on "Studies of X-rays from mu-mesonic atoms". [8] The thesis was published in the Physical Review in November 1953. [9]

In 1949, Fitch married Elise Cunningham, a secretary who worked in the laboratory at Columbia. They had two sons. Elise died in 1972, and in 1976 he married Daisy Harper Sharp, thereby acquiring two stepdaughters and a stepson. [4] [10] After obtaining his doctorate, Fitch's interest shifted to strange particles and K mesons. He took a position at Princeton University, where he spent the rest of his career. He became a professor in 1960, Fogg Brackett Professor in 1976, and McDonnell Distinguished University Professor of Physics in 1987, retaining this position until his retirement in 2005. He was chair of the Physics Department from 1976 to 1981. [5]

Fitch conducted much of his research at the Brookhaven National Laboratory, where he became acquainted with James Cronin. The two of them played bridge at nights while they waited for the Cosmotron to become available. Cronin had built a new kind of detector, a spark chamber spectrometer, and Fitch realized that it would be perfect for experiments with K mesons (now known as kaons), which Yale University physicist Robert Adair had suggested had interesting properties worth investigating. They could decay into either matter or antimatter. Along with two colleagues, James Christenson and René Turlay, they set up their experiment on the Alternating Gradient Synchrotron at Brookhaven. They discovered an unexpected result. The decay of neutral K mesons did not respect CP symmetry. K mesons that decayed into positrons did so faster than those that decayed into electrons. [10] [11] [12] The importance of this result was not immediately appreciated; but as evidence of the Big Bang accumulated, Andrei Sakharov realized in 1967 that it explained why the universe is largely made of matter and not antimatter. [10] Put simply, they had found "the answer to the physicist's 'Why do we exist?'" [13] For this discovery, Fitch and Cronin received the 1980 Nobel Prize in Physics. [1]

In addition to the Nobel Prize, Fitch received the Ernest Orlando Lawrence Award in 1968, the John Price Wetherill Medal in 1976 and the National Medal of Science in 1993. [4] He was a member of the Board of Sponsors of the Bulletin of the Atomic Scientists and the JASON defense advisory group. [14] He was elected to the National Academy of Sciences in 1966. [15] In 1981, Fitch became a founding member of the World Cultural Council. [16] He was president of the American Physical Society from 1988 to 1989, and he served on a number of governmental science and science policy committees, including the President's Science Advisory Committee from 1970 to 1973. [5] He died at his home in Princeton, New Jersey, at the age of 91 on February 5, 2015. [5] [10]


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  1. 1 2 3 4 5 6 7 8 "Val Fitch – Biographical". Nobel Foundation. Retrieved February 13, 2015.
  2. 1 2 3 4 5 6 "Interview with Val Fitch by Finn Aserud on December 18, 1986". Niels Bohr Library and Archives, American Institute of Physics. Retrieved May 15, 2015.
  3. "Interview with Val Fitch". Nobel Foundation. Retrieved May 15, 2015.
  4. 1 2 3 "Val Fitch". Soylent Communications. Retrieved May 15, 2015.
  5. 1 2 3 4 Zandonella, Catherine (February 6, 2015). "Nobel laureate and Princeton physicist Val Fitch dies at age 91". Princeton University.
  6. Keefer, Louis E. "The Army Specialized Training Program In World War II" . Retrieved May 15, 2015.
  7. 1 2 "All in Our Time: The View from the Bottom". Bulletin of the Atomic Scientists. 31 (2): 43–46. February 1975. Retrieved May 15, 2015.
  8. "Studies of X-rays from Mu-Mesonic atoms". Columbia University. 1954. Retrieved May 15, 2015.
  9. Fitch, Val L.; Rainwater, James (November 1953). "Studies of X-Rays from Mu-Mesonic Atoms". Physical Review . American Physical Society. 92 (3): 789–800. Bibcode:1953PhRv...92..789F. doi:10.1103/PhysRev.92.789.
  10. 1 2 3 4 Dennis Overbye (February 10, 2015). "Val Fitch, Who Discovered Universe to Be Out of Balance, Is Dead at 91". The New York Times . Retrieved February 11, 2015. Val Fitch, who shared the 1980 Nobel Prize in Physics for work that revealed a surprising imbalance in the laws of nature and helped explain why the collision of matter and antimatter has not destroyed everything in the universe, died on Thursday at his home in Princeton, N.J. He was 91. ...
  11. Christenson, J. H.; Cronin, J. W.; Fitch, V. L.; Turlay, R. (July 1964). "Evidence for the 2π Decay of the K20 Meson". Physical Review Letters. American Physical Society. 13 (4): 138–140. Bibcode:1964PhRvL..13..138C. doi:10.1103/PhysRevLett.13.138.
  12. Cronin, James W. (December 8, 1980). "CP Symmetry Violation – The Search for Its Origin (Nobel lecture)" (PDF). Retrieved May 15, 2015.
  13. "Matter, Antimatter, and Why are We Here: CP violation may be the reason" (PDF). FermiNews. April 17, 1998. Retrieved May 15, 2015.
  14. Horgan, John (April 16, 2006). "Rent-a-Genius". The New York Times.
  15., National Academy of Sciences -. "Val Fitch". Retrieved April 3, 2018.
  16. "About Us". World Cultural Council . Retrieved November 8, 2016.