Carl David Anderson (September 3, 1905 – January 11, 1991) was an American particle physicist who shared the 1936

Nobel Prize in Physics The Nobel Prize in Physics () is an annual award given by the Royal Swedish Academy of Sciences for those who have made the most outstanding contributions to mankind in the field of physics. It is one of the five Nobel Prizes established by the ...

with Victor Francis Hess for his discovery of the

positron The positron or antielectron is the particle with an electric charge of +1''elementary charge, e'', a Spin (physics), spin of 1/2 (the same as the electron), and the same Electron rest mass, mass as an electron. It is the antiparticle (antimatt ...

Biography

Anderson was born in

New York City New York, often called New York City (NYC), is the most populous city in the United States, located at the southern tip of New York State on one of the world's largest natural harbors. The city comprises five boroughs, each coextensive w ...

, the son of Swedish immigrants. He studied

physics Physics is the scientific study of matter, its Elementary particle, fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge whi ...

and

engineering Engineering is the practice of using natural science, mathematics, and the engineering design process to Problem solving#Engineering, solve problems within technology, increase efficiency and productivity, and improve Systems engineering, s ...

Caltech The California Institute of Technology (branded as Caltech) is a private university, private research university in Pasadena, California, United States. The university is responsible for many modern scientific advancements and is among a small g ...

( B.S., 1927; Ph.D., 1930). Under the supervision of Robert A. Millikan, he began investigations into cosmic rays during the course of which he encountered unexpected

particle In the physical sciences, a particle (or corpuscle in older texts) is a small localized object which can be described by several physical or chemical properties, such as volume, density, or mass. They vary greatly in size or quantity, from s ...

tracks in his (modern versions now commonly referred to as an Anderson) cloud chamber photographs that he correctly interpreted as having been created by a particle with the same mass as the

electron The electron (, or in nuclear reactions) is a subatomic particle with a negative one elementary charge, elementary electric charge. It is a fundamental particle that comprises the ordinary matter that makes up the universe, along with up qua ...

, but with opposite

electrical charge Electricity is the set of physical phenomena associated with the presence and motion of matter possessing an electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by Maxwel ...

. This discovery, announced in 1932 and later confirmed by others, validated

Paul Dirac Paul Adrien Maurice Dirac ( ; 8 August 1902 – 20 October 1984) was an English mathematician and Theoretical physics, theoretical physicist who is considered to be one of the founders of quantum mechanics. Dirac laid the foundations for bot ...

's theoretical prediction of the existence of the

. Anderson first detected the particles in cosmic rays. He then produced more conclusive proof by shooting

gamma ray A gamma ray, also known as gamma radiation (symbol ), is a penetrating form of electromagnetic radiation arising from high energy interactions like the radioactive decay of atomic nuclei or astronomical events like solar flares. It consists o ...

s produced by the natural radioactive nuclide ThC'' ( ²⁰⁸Tl) into other materials, resulting in the creation of positron-electron pairs. For this work, Anderson shared the 1936

with Victor Hess. Fifty years later, Anderson acknowledged that his discovery was inspired by the work of his Caltech classmate Chung-Yao Chao, whose research formed the foundation from which much of Anderson's work developed but was not credited at the time. Also in 1936, Anderson and his first graduate student, Seth Neddermeyer, discovered a

muon A muon ( ; from the Greek letter mu (μ) used to represent it) is an elementary particle similar to the electron, with an electric charge of −1 '' e'' and a spin of ''ħ'', but with a much greater mass. It is classified as a ...

(or 'mu-meson', as it was known for many years), a

subatomic particle In physics, a subatomic particle is a particle smaller than an atom. According to the Standard Model of particle physics, a subatomic particle can be either a composite particle, which is composed of other particles (for example, a baryon, lik ...

207 times more massive than the

, but with the same negative electric charge and spin 1/2 as the electron, again in cosmic rays. Anderson and Neddermeyer at first believed that they had seen a

pion In particle physics, a pion (, ) or pi meson, denoted with the Greek alphabet, Greek letter pi (letter), pi (), is any of three subatomic particles: , , and . Each pion consists of a quark and an antiquark and is therefore a meson. Pions are the ...

, a particle which Hideki Yukawa had postulated in his theory of the

strong interaction In nuclear physics and particle physics, the strong interaction, also called the strong force or strong nuclear force, is one of the four known fundamental interaction, fundamental interactions. It confines Quark, quarks into proton, protons, n ...

. When it became clear that what Anderson had seen was ''not'' the pion, the physicist I. I. Rabi, puzzled as to how the unexpected discovery could fit into any logical scheme of

particle physics Particle physics or high-energy physics is the study of Elementary particle, fundamental particles and fundamental interaction, forces that constitute matter and radiation. The field also studies combinations of elementary particles up to the s ...

, quizzically asked "Who ordered ''that''?" (sometimes the story goes that he was dining with colleagues at a Chinese restaurant at the time). The

was the first of a long list of

subatomic particles In physics, a subatomic particle is a particle smaller than an atom. According to the Standard Model of particle physics, a subatomic particle can be either a composite particle, which is composed of other particles (for example, a baryon, like ...

whose discovery initially baffled theoreticians who could not make the confusing "zoo" fit into some tidy conceptual scheme.

Willis Lamb Willis Eugene Lamb Jr. (; July 12, 1913 – May 15, 2008) was an American physicist who shared the 1955 Nobel Prize in Physics with Polykarp Kusch "for his discoveries concerning the fine structure of the hydrogen spectrum". Lamb was able to p ...

, in his 1955 Nobel Prize Lecture, joked that he had heard it said that "the finder of a new elementary particle used to be rewarded by a Nobel Prize, but such a discovery now ought to be punished by a 10,000 dollar fine." Anderson spent all of his academic and research career at

. During

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

, he conducted research in

rocket A rocket (from , and so named for its shape) is a vehicle that uses jet propulsion to accelerate without using any surrounding air. A rocket engine produces thrust by reaction to exhaust expelled at high speed. Rocket engines work entirely ...

ry there. He was elected to the United States

National Academy of Sciences The National Academy of Sciences (NAS) is a United States nonprofit, NGO, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the ...

and the

American Philosophical Society The American Philosophical Society (APS) is an American scholarly organization and learned society founded in 1743 in Philadelphia that promotes knowledge in the humanities and natural sciences through research, professional meetings, publicat ...

in 1938. He was elected a Fellow of the

American Academy of Arts and Sciences The American Academy of Arts and Sciences (The Academy) is one of the oldest learned societies in the United States. It was founded in 1780 during the American Revolution by John Adams, John Hancock, James Bowdoin, Andrew Oliver, and other ...

in 1950. He received the Elliott Cresson Medal of the Franklin Institute in 1937 and the Golden Plate Award of the American Academy of Achievement in 1975. He died on January 11, 1991, in San Marino, California. His remains were interred in the Forest Lawn, Hollywood Hills Cemetery in

Los Angeles, California Los Angeles, often referred to by its initials L.A., is the List of municipalities in California, most populous city in the U.S. state of California, and the commercial, Financial District, Los Angeles, financial, and Culture of Los Angeles, ...

. In 1946, he married Lorraine Bergman, with whom he had two sons.

Select publications

* * *

References

External links

1983 Audio Interview with Carl Anderson by Martin Sherwin
Voices of the Manhattan Project * American National Biography, vol. 1, pp. 445–446.
Annotated bibliography for Carl David Anderson from the Alsos Digital Library for Nuclear Issues

*
National Academy of Sciences Biographical Memoir

Oral History interview transcript with Carl D. Anderson on 30 June 1966, American Institute of Physics, Niels Bohr Library and Archives
* {{DEFAULTSORT:Anderson, Carl David 1905 births 1991 deaths 20th-century American physicists American Nobel laureates American people of Swedish descent Burials at Forest Lawn Memorial Park (Hollywood Hills) California Institute of Technology alumni California Institute of Technology faculty American experimental physicists Fellows of the American Academy of Arts and Sciences Fellows of the American Physical Society John H. Francis Polytechnic High School alumni Nobel laureates in Physics American particle physicists Scientists from California Scientists from New York City Members of the United States National Academy of Sciences Members of the American Philosophical Society

Biography

Select publications

References

Further reading

External links