crème de la crème

Jai Ganesh · 2025-11-09 16:39:42

2389) Robert S. Mulliken

Gist:

Work

The world around us consists of molecules that are composed of atoms. In Niels Bohr’s atomic model, which is based on principles of quantum physics, electrons circle the atomic nucleus in different shells that contain a fixed number of electrons. The assumption was that attractive forces between the atoms in a molecule are the result of atoms sharing electrons to fill the electron shells. Beginning in the mid-1920s, Robert Mulliken applied quantum mechanics to the development of sophisticated models for the movement of electrons within a molecule, so-called molecular orbitals.

Summary

Robert Sanderson Mulliken (born June 7, 1896, Newburyport, Mass., U.S.—died Oct. 31, 1986, Arlington, Va.) was an American chemist and physicist who received the 1966 Nobel Prize for Chemistry for “fundamental work concerning chemical bonds and the electronic structure of molecules.”

A graduate of the Massachusetts Institute of Technology, Mulliken worked, during World War I and for a few years afterward, in government chemical research. He then studied under the physicist Robert A. Millikan at the University of Chicago, receiving his Ph.D. in 1921. He taught at New York University (1926–28) and then joined the faculty of the University of Chicago (1928–85).

Mulliken began working on his theory of molecular structure in the 1920s. He theoretically systematized the electron states of molecules in terms of molecular orbitals. Departing from the idea that electron orbitals for atoms are static and that atoms combine like building blocks to form molecules, he proposed that, when molecules are formed, the atoms’ original electron configurations are changed into an overall molecular configuration. Further extending his theory, he developed (1952) a quantum-mechanical theory of the behaviour of electron orbitals as different atoms merge to form molecules.

During World War II Mulliken worked on the Plutonium Project, part of the development of the atomic bomb, at the University of Chicago. In 1955 he served as scientific attaché at the U.S. embassy in London.

Details

Robert Sanderson Mulliken ForMemRS[1] (June 7, 1896 – October 31, 1986) was an American physical chemist, primarily responsible for the early development of molecular orbital theory, i.e. the elaboration of the molecular orbital method of computing the structure of molecules. Mulliken received the Nobel Prize in Chemistry in 1966 and the Priestley Medal in 1983.[2]

Early years

Robert Mulliken was born in Newburyport, Massachusetts on June 7 1896. His father, Samuel Parsons Mulliken, was a professor of organic chemistry at the Massachusetts Institute of Technology. As a child, Robert Mulliken learned the name and botanical classification of plants and, in general, had an excellent, but selective, memory. For example, he learned German well enough to skip the course in scientific German in college, but could not remember the name of his high school German teacher. He also made the acquaintance, while still a child, of the physical chemist Arthur Amos Noyes.

Mulliken helped with some of the editorial work when his father wrote his four-volume text on organic compound identification, and thus became an expert on organic chemical nomenclature.

Education

In high school in Newburyport, Mulliken followed a scientific curriculum. He graduated in 1913 and succeeded in getting a scholarship to MIT which had earlier been won by his father. Like his father, he majored in chemistry. Already as an undergraduate, he conducted his first publishable research: on the synthesis of organic chlorides. Because he was unsure of his future direction, he included some chemical engineering courses in his curriculum and spent a summer touring chemical plants in Massachusetts and Maine. He received his B. S. degree in chemistry from MIT in 1917.

Early career

At this time, the United States had just entered World War I, and Mulliken took a position at American University in Washington, D.C., making poison gas under James B. Conant. After nine months, he was drafted into the Army's Chemical Warfare Service, but continued on the same task. His laboratory techniques left much to be desired, and he was out of service for months with burns. Later, he contracted a bad case of influenza, and was still hospitalized at war's end.

After the war, he took a job investigating the effects of zinc oxide and carbon black on rubber, but quickly decided that this was not the kind of chemistry he wanted to pursue. Hence, in 1919 he entered the Ph.D. program at the University of Chicago.

Graduate and early postdoctoral education

Mulliken got his doctorate in 1921 based on research into the separation of isotopes of mercury by evaporation, and continued in his isotope separation by this method. While at Chicago, he took a course under the Nobel Prize-winning physicist Robert A. Millikan, which exposed him to the old quantum theory. He also became interested in strange molecules after exposure to work by Hermann I. Schlesinger on diborane.

At Chicago, he had received a grant from the National Research Council (NRC) which had paid for much of his work on isotope separation. The NRC grant was extended in 1923 for two years so he could study isotope effects on band spectra of such diatomic molecules as boron nitride (BN) (comparing molecules with B10 and B11). He went to Harvard University to learn spectrographic technique from Frederick A. Saunders and quantum theory from E. C. Kemble. At the time, he was able to associate with J. Robert Oppenheimer and many future Nobel laureates, including John H. Van Vleck and Harold C. Urey. He also met John C. Slater, who had worked with Niels Bohr.

In 1925 and 1927, Mulliken traveled to Europe, working with outstanding spectroscopists and quantum theorists such as Erwin Schrödinger, Paul A. M. Dirac, Werner Heisenberg, Louis de Broglie, Max Born, and Walther Bothe (all of whom eventually received Nobel Prizes) and Friedrich Hund, who was at the time Born's assistant. They all, as well as Wolfgang Pauli, were developing the new quantum mechanics that would eventually supersede the old quantum theory. Mulliken was particularly influenced by Hund, who had been working on quantum interpretation of band spectra of diatomic molecules, the same spectra which Mulliken had investigated at Harvard. In 1927 Mulliken worked with Hund and as a result developed his molecular orbital theory, in which electrons are assigned to states that extend over an entire molecule. In consequence, molecular orbital theory was also referred to as the Hund-Mulliken theory.

Early scientific career

From 1926 to 1928, he taught in the physics department at New York University (NYU). This was his first recognition as a physicist. Though his work had been considered important by chemists, it clearly was on the borderline between the two sciences and both would claim him from this point on. Then he returned to the University of Chicago as an associate professor of physics, being promoted to full professor in 1931. He ultimately held a position jointly in both the physics and chemistry departments. At both NYU and Chicago, he continued to refine his molecular-orbital theory.

Up to this point, the primary way to calculate the electronic structure of molecules was based on a calculation by Walter Heitler and Fritz London on the hydrogen molecule (H2) in 1927. With the conception of hybridized atomic orbitals by John C. Slater and Linus Pauling, which rationalized observed molecular geometries, the method was based on the premise that the bonds in any molecule could be described in a manner similar to the bond in H2, namely, as overlapping atomic orbitals centered on the atoms involved. Since it corresponded to chemists' ideas of localized bonds between pairs of atoms, this method (called the Valence-Bond (VB) or Heitler-London-Slater-Pauling (HLSP) method), was very popular. In attempting to calculate the properties of excited states (molecules that have been excited by an energy source), the VB method does not always work well. With its description of the electron wave functions in molecules as delocalized molecular orbitals that possess the same symmetry as the molecule, Hund and Mulliken's molecular-orbital method, including contributions by John Lennard-Jones, proved to be more flexible and applicable to a vast variety of types of molecules and molecular fragments, and has eclipsed the valence-bond method. As a result of this development, he received the Nobel Prize in Chemistry in 1966.

Mulliken became a member of the National Academy of Sciences in 1936, the youngest member in the organization's history at the time. He was elected to the American Philosophical Society in 1940 and the American Academy of Arts and Sciences in 1965. He was elected a Foreign Member of the Royal Society (ForMemRs) in 1967.

Mulliken population analysis is named after him, a method of assigning charges to atoms in a molecule.

Personal life

On December 24, 1929, he married Mary Helen von Noé, daughter of Adolf Carl Noé, a geology professor at the University of Chicago. They had two daughters.

Later years

In 1934, he derived a new scale for measuring the electronegativity of elements, which he defined as the average of an atom's ionization enthalpy and electron affinity. This does not entirely correlate with the scale of Linus Pauling, but is generally in close correspondence.

In World War II, from 1942 to 1945, he directed the Information Office for the University of Chicago's Plutonium project. Afterward, he developed mathematical formulas to enable the progress of the molecular-orbital theory.

In 1952. he began to apply quantum mechanics to the analysis of the reaction between Lewis acid and base molecules. In 1961, he became Distinguished Professor of Physics and Chemistry at Florida State University, and continued in his studies of molecular structure and spectra, ranging from diatomic molecules to large complex aggregates. In 1981, Mulliken became a founding member of the World Cultural Council. In 1983, Mulliken received the Golden Plate Award of the American Academy of Achievement. He retired in 1985. His wife died in 1975.

At the age of 90, Mulliken died of congestive heart failure at his daughter's home in Arlington County, Virginia on October 31, 1986. His body was returned to Chicago for burial.

Jai Ganesh · 2025-11-10 17:03:13

2390) Francis Peyton Rous

Gist:

Work

In cancer, cells grow and multiply beyond normal limits. In 1910 Peyton Rous extracted material from a cancer tumor in a hen and injected it into a healthy chicken. The chicken developed cancer, and he concluded that cells from the hen’s tumor contained an infectious substance, a virus, that transmits cancer. However, the study could not be replicated in mammals and was long overlooked. When research showed that viruses can operate by affecting the genetic material of normal germ cells, interest in Rous’ discovery was reignited.

Summary:

Peyton Rous (born October 5, 1879, Baltimore, Maryland, U.S.—died February 16, 1970, New York, New York) was an American pathologist whose discovery of cancer-inducing viruses earned him a share of the Nobel Prize for Physiology or Medicine in 1966.

Rous was educated at Johns Hopkins University, Baltimore, and at the University of Michigan. He joined the Rockefeller Institute for Medical Research (now Rockefeller University) in New York City in 1909 and remained there throughout his career. In 1911 Rous found that sarcomas in hens could be transmitted to fowl of the same inbred stock not only by grafting tumour cells but also by injecting a submicroscopic agent extractable from them; this discovery gave rise to the virus theory of cancer causation. Although his research was derided at the time, subsequent experiments vindicated his thesis, and he received belated recognition in 1966 when he was awarded (with Charles B. Huggins) the Nobel Prize.

Aside from cancer research, Rous did investigations of liver and gallbladder physiology, and he worked on the development of blood-preserving techniques that made the first blood banks possible.

Details

Francis Peyton Rous (October 5, 1879 – February 16, 1970) was an American pathologist at the Rockefeller University known for his works in oncoviruses, blood transfusion and physiology of digestion. A medical graduate from the Johns Hopkins University, he was discouraged from becoming a practicing physician due to severe tuberculosis. After three years of working as an instructor of pathology at the University of Michigan, he became dedicated researcher at the Rockefeller Institute for Medical Research for the rest of his career.

His discovery in 1911 that a chicken tumor was caused by a virus (later named Rous sarcoma virus) led to more discoveries and understanding of the role of viruses in the development of certain types of cancer. He was awarded a Nobel Prize in Physiology or Medicine for his work in 1966, 55 years after his initial discovery and he remains the oldest recipient of the Nobel Prize in Medicine or Physiology.

He and Joseph R. Turner studied methods to make use of blood types for blood transfusion. During World War I, they developed a technique for preserving blood sample by using an acid, citrate. This enabled the first practical storage of blood samples for transfusion and was introduced by Oswald H. Robertson at the front line in Belgium in 1917 as the world's first blood bank.

Awards and honors

Rous was elected a member of the United States National Academy of Sciences in 1927 and a member of the American Philosophical Society in 1939. He was elected a Foreign Member of the Royal Society (ForMemRS) in 1940. He received the Albert Lasker Award for Basic Medical Research in 1958 and the National Medal of Science in 1965. He was also member of the Royal Society of Medicine, the Royal Danish Academy of Sciences and Letters, and the Norwegian Academy of Science and Letters. He was appointed honorary fellow of the Weizmann Institute of Science and foreign correspondent of the Académie Nationale de Médecine in Paris. He also received the Kovalenko Medal of the National Academy of Sciences, the Distinguished Service Award of the American Cancer Society, the United Nations Prize for Cancer Research, and the Paul Ehrlich and Ludwig Darmstaedter Prize from the Federal Republic of Germany.

Rous shared the Nobel Prize in Physiology or Medicine in 1966 with Charles Brenton Huggins "for his discovery of tumour-inducing viruses." As early as 1926, Karl Landsteiner had nominated him and subsequently received other 16 nominations up to 1951, but was selected 55 years after his initial discovery at the age of 87, and he is recorded as the oldest recipient of the Nobel Prize in Medicine or Physiology. His remains "the longest 'incubation period' in the 110 years history of the Nobel Prizes in Physiology or Medicine."

Personal life

Rous married Marion Eckford de Kay in 1915 who survived him by fifteen years and died in 1985. He had three daughters, Marion (Marni), Ellen and Phoebe. Marni (1917–2015) was a children's book editor, and the wife of another Nobel Prize winner, Alan Lloyd Hodgkin. Phoebe married Thomas J. Wilson, director of the Harvard University Press.

In his later life he wrote biographies of Simon Flexner and Karl Landsteiner.

Death

Rous died in 1970 of abdominal cancer at the Memorial Sloan Kettering Cancer Center in New York. His wife died in 1985.

Jai Ganesh · 2025-11-11 17:26:55

2391) Charles Brenton Huggins

Gist:

Work

In cancer, cells grow and multiply beyond normal limits. Prostate cancer, which attacks a gland that is part of the male gender organ, is one of the more common forms of cancer. Around 1940 Charles Huggins showed that the course of the disease can be affected by hormones. If the production of male gender hormone is prevented through castration or if female gender hormone is added, the cancer could be counteracted. Hormone treatment for prostate cancer quickly gained traction. Huggins also developed hormone treatment for breast cancer.

Summary:

Charles B. Huggins (born Sept. 22, 1901, Halifax, Nova Scotia, Can.—died Jan. 12, 1997, Chicago, Ill., U.S.) was a Canadian-born American surgeon and urologist whose investigations demonstrated the relationship between hormones and certain types of cancer. For his discoveries, Huggins received (with Peyton Rous) the Nobel Prize for Physiology or Medicine in 1966.

Huggins was educated at Acadia University (Wolfville, N.S.) and at Harvard University, where he received his M.D. in 1924. He went to the University of Michigan for further training in surgery (1924–27) and then joined the faculty of the University of Chicago, where he served as director of the Ben May Laboratory for Cancer Research from 1951 to 1969.

Huggins was a specialist on the male urological and genital tract. In the early 1940s he found he could retard the growth of prostate cancer by blocking the action of the patient’s male hormones with doses of the female hormone estrogen. This research demonstrated that some cancer cells, like normal body cells, are dependent on hormonal signals to survive and grow and that, by depriving cancer cells of the correct signals, the growth of tumours could be slowed down, at least temporarily. In 1951 Huggins showed that breast cancers are also dependent on specific hormones. By removing the ovaries and adrenal glands, which are the source of estrogen, he could achieve significant tumour regression in some of his patients. Owing to his work, drugs that block the body’s production of estrogen became important resources in treating breast cancer.

Details

Charles Brenton Huggins (September 22, 1901 – January 12, 1997) was a Canadian-American surgeon and physiologist known for his work on prostate function, prostate cancer, and breast cancer. Born in Halifax in 1901, Huggins moved to the United States for medical school. He was one of the founding staff members of the University of Chicago Medical School, where he remained for the duration of his professional research career. Huggins's work on how gender hormones influence prostate function ultimately led to his discovery of hormone therapies to treat prostate cancer. For this finding, he was awarded the 1966 Nobel Prize for Physiology or Medicine. In addition to his work on prostate cancer, Huggins explored the relationship between hormones and breast cancer, developed an animal model for breast cancer, and developed chromogenic substrates that are widely used for biochemical analyses. Huggins continued to perform research into his 90s; he died in Chicago in 1997.

Early life and education

Charles Brenton Huggins was born September 22nd, 1901, in Halifax, Nova Scotia, to Charles E. Huggins and Bessie Maria Spencer. At 19, he graduated from Acadia University with a BA degree, supplementing his Acadia coursework with summer courses in physical and organic chemistry at Columbia University. Huggins went on to Harvard Medical School, and received his MD degree in 1924. He served his internship and residency in general surgery with Frederick A. Coller at the University of Michigan. While at Michigan, Huggins met operating room nurse Margaret Wellman; they married in 1927.

Academic career

In 1927, Huggins was recruited to the new University of Chicago Medical School by chairman of surgery Dallas Phemister. As one of the eight original staff members of the school, Huggins was assigned to the urology department, and had to rapidly teach himself the specialty. In 1931, Phemister offered Huggins a paid research sabbatical in Europe; Huggins spent several months at London's Lister Institute working in Robert Robison's lab to deepen his knowledge in biochemistry. He was promoted to associate professor in 1933, and full professor in 1936.

In 1951, businessman and longtime financial supporter of Huggins's research Ben E. May endowed the Ben May Laboratory for Cancer Research at the University of Chicago. Huggins eventually became the May Laboratory's director, serving in the position until 1969. In 1962, he was granted an endowed professorship, the William B. Ogden Distinguished Service Professor.

Notable students of Professor Huggins included Howard Guy Williams-Ashman, Shutsung Liao, Paul Talalay and A. Hari Reddi.

Research

A plaque in Professor's Huggins office carried his motto: "Discovery is our business." This motto signified his ethos to research and medical discovery.

Huggins's early research work focused on bone physiology. However, he eventually felt this bone work was unlikely to lead to medical progress, and set it aside in favor of studying the male urogenital tract. Through the 1930s, Huggins published work characterizing the constituents of semen and which organ (seminal vesicles or prostate) they derive from. In 1939, Huggins described a method for isolating prostate fluid from dogs, which served as the foundation for much of his subsequent work. He showed that the prostate requires androgens (male gender hormones) in order to function, and that androgen treatment could be counteracted by treatment with estrogens. In the course of this work, he discovered that older dogs tended to have enlarged prostates, and that these enlarged prostates could be shrunk by administering estrogen.

In 1940 and 1941, Huggins – along with students Clarence V. Hodges and William Wallace Scott – published a series of three papers detailing his most famous finding: that counteracting androgen activity by orchiectomy (surgical removal of the testicles) or estrogen treatment shrank tumors in many men with metastatic prostate cancer. These men experienced dramatic pain relief within days of the treatment; four of the original 21 treated went on to survive more than 12 years from the original treatment.

Huggins's work on prostate cancer often necessitated measuring the amount of prostate-derived enzymes in the blood. To this end, Huggins developed colorimetric methods for quantifying the concentration of various phosphatases, glucuronidases, and esterases. These assays relied on chromogenic substrates (substances that change color in response to a given enzyme), a term Huggins coined, and a concept he pioneered.

In the 1950s, Huggins went on to show an analogous relationship between gender hormones and breast cancer – tumor growth was stimulated by estrogens, and slowed by androgens. At the time breast cancer research was hindered by the lack of an animal model. Huggins described the first reliable model: 7,12-dimethylbenz(a)anthracene administered orally to rats, 100% of which rapidly developed breast tumors; the model is now called Huggins's tumor. Around this time, Huggins wound down his surgical practice, turning his attention to full-time scientific research.

Huggins published over 200 peer-reviewed papers describing his research.

Honours

Huggins was elected to the United States National Academy of Sciences and the American Academy of Arts and Sciences in 1949. In 1962, he was elected to the American Philosophical Society, and was awarded the Lasker Award the following year. In 1966, following nominations from noted surgeon J. Hartwell Harrison as well as Nobel laureates Otto H. Warburg, William P. Murphy, and Albert Szent-Györgyi, Huggins was awarded the Nobel Prize in Physiology or Medicine "for his discoveries concerning hormonal treatment of prostatic cancer". From 1972 to 1979, Huggins was named the ceremonial chancellor of his alma mater, Acadia University. His prize, shared with fellow cancer researcher Peyton Rous, was just the second Nobel for cancer treatment or research.

Personal life

Huggins and his wife Margaret had a son and a daughter. His son, Charles E. Huggins, was also a surgeon, and directed the Massachusetts General Hospital blood bank until his death in 1990. Margaret Huggins died in 1983. Huggins devoted much of his time to laboratory work, logging long hours in the lab, and continuing to perform hands-on laboratory work in his 90s. Huggins died on January 12, 1997, in Chicago, Illinois, aged 95.

Jai Ganesh · Yesterday 17:50:02

2392) Shin'ichirō Tomonaga

Gist:

Work

Following the establishment of the theory of relativity and quantum mechanics, an initial relativistic theory was formulated for the interaction between charged particles and electromagnetic fields. The theory had to be reformulated, however, partly due to the observation of the Lamb shift in 1947, in which the supposed single energy level within a hydrogen atom was instead proven to be two similar levels. Sin-Itiro Tomonga solved this problem in 1948 through a “renormalization” and thereby contributed to a new quantum electrodynamics.

Summary

Tomonaga Shin’ichirō (born March 31, 1906, Kyōto, Japan—died July 8, 1979, Tokyo) was a Japanese physicist, joint winner, with Richard P. Feynman and Julian S. Schwinger of the United States, of the Nobel Prize for Physics in 1965 for developing basic principles of quantum electrodynamics.

Tomonaga became professor of physics at Bunrika University (later Tokyo University of Education) in 1941, the year he began his investigations of the problems of quantum electrodynamics. World War II isolated him from Western scientists, but in 1943 he completed and published his research. Tomonaga’s theoretical work made quantum electrodynamics (the theory of the interactions of charged subatomic particles with the electromagnetic field) consistent with the theory of special relativity. It was only after the war, in 1947, that his work came to the attention of the West, at about the same time that Feynman and Schwinger published the results of their research. It was found that all three had achieved essentially the same result from different approaches and had resolved the inconsistencies of the old theory without making any drastic changes.

Tomonaga was president of the Tokyo University of Education from 1956 to 1962, and the following year he was named chairman of the Japan Science Council. Throughout his life Tomonaga actively campaigned against the spread of nuclear weapons and urged that resources be spent on the peaceful use of nuclear energy. Most notable of his works available in English translation are Quantum Mechanics (1962) and his Nobel lecture Development of Quantum Electrodynamics: Personal Recollections (1966).

Details

Shinichiro Tomonaga (Tomonaga Shin'ichirō; March 31, 1906 – July 8, 1979), usually cited as Sin-Itiro Tomonaga in English, was a Japanese physicist, influential in the development of quantum electrodynamics, work for which he was jointly awarded the Nobel Prize in Physics in 1965 along with Richard Feynman and Julian Schwinger.

Biography

Tomonaga was born in Tokyo in 1906. He was the second child and eldest son of a Japanese philosopher, Tomonaga Sanjūrō. He entered the Kyoto Imperial University in 1926. Hideki Yukawa, also a Nobel laureate, was one of his classmates during undergraduate school. During graduate school at the same university, he worked as an assistant in the university for three years. In 1931, after graduate school, he joined Nishina's group in RIKEN. In 1937, while working at Leipzig University (Leipzig), he collaborated with the research group of Werner Heisenberg. Two years later, he returned to Japan due to the outbreak of the Second World War, but finished his doctoral degree (Dissertation PhD from University of Tokyo) on the study of nuclear materials with his thesis on work he had done while in Leipzig.

In Japan, he was appointed to a professorship in the Tokyo University of Education (a forerunner of Tsukuba University). During the war he studied the magnetron, meson theory, and his super-many-time theory. In 1948, he and his students re-examined a 1939 paper by Sidney Dancoff that attempted, but failed, to show that the infinite quantities that arise in quantum electrodynamics (QED) can be canceled with each other. Tomonaga applied his super-many-time theory and a relativistic method based on the non-relativistic method of Wolfgang Pauli and Fierz to greatly speed up and clarify the calculations. Then he and his students found that Dancoff had overlooked one term in the perturbation series. With this term, the theory gave finite results; thus Tomonaga discovered the renormalization method independently of Julian Schwinger and calculated physical quantities such as the Lamb shift at the same time.

In 1949, he was invited by Robert Oppenheimer to work at the Institute for Advanced Study in Princeton. He studied a many-body problem on the collective oscillations of a quantum-mechanical system. In the following year, he returned to Japan and proposed the Tomonaga–Luttinger liquid. In 1955, he took the leadership in establishing the Institute for Nuclear Study, University of Tokyo. In 1965, he was awarded the Nobel Prize in Physics, with Julian Schwinger and Richard P. Feynman, for the study of QED, specifically for the discovery of the renormalization method. He died of throat cancer in Tokyo in 1979.

Tomonaga was married in 1940 to Ryōko Sekiguchi. They had two sons and one daughter. He was awarded the Order of Culture in 1952, and the Grand Cordon of the Order of the Rising Sun in 1976.

In recognition of three Nobel laureates' contributions, the bronze statues of Shin'ichirō Tomonaga, Leo Esaki, and Makoto Kobayashi was set up in the Central Park of Azuma 2 in Tsukuba City in 2015.

Jai Ganesh · Today 17:38:17

2393) Julian Schwinger

Gist:

Work

Following the establishment of the theory of relativity and quantum mechanics, an initial relativistic theory was formulated for the interaction between charged particles and electromagnetic fields. However, partly because the electron’s magnetic moment proved to be somewhat larger than expected, the theory had to be reformulated. Julian Schwinger solved this problem in 1948 through “renormalization” and thereby contributed to a new quantum electrodynamics.

Summary

Julian Seymour Schwinger (born Feb. 12, 1918, New York, N.Y., U.S.—died July 16, 1994, Los Angeles, Calif.) was an American physicist and joint winner, with Richard P. Feynman and Tomonaga Shin’ichirō, of the Nobel Prize for Physics in 1965 for introducing new ideas and methods into quantum electrodynamics.

Schwinger was a child prodigy, publishing his first physics paper at age 16. He earned a bachelor’s degree (1937) and a doctorate (1939) from Columbia University in New York City, before engaging in postdoctoral studies at the University of California at Berkeley with physicist J. Robert Oppenheimer. Schwinger left Berkeley in the summer of 1941 to accept an instructorship at Purdue University, West Lafayette, Ind., and in 1943 he joined the Radiation Laboratory at the Massachusetts Institute of Technology, where many scientists had been assembled to help with wartime research on radar. In the fall of 1945 Schwinger accepted an appointment at Harvard University and in 1947 became one of the youngest full professors in the school’s history. From 1972 until his death, Schwinger was a professor in the physics department at the University of California at Los Angeles.

Schwinger was one of the participants at the meeting held in June 1947 on Shelter Island, Long Island, N.Y., at which reliable experimental data were presented that contradicted the predictions of the English theoretical physicist P.A.M. Dirac’s relativistic quantum theory of the electron. In particular, experimental data contradicted Dirac’s prediction that certain hydrogen electron stationary states were degenerate (i.e., had the same energy as certain other states) as well as Dirac’s prediction for the value of the magnetic moment of the electron. Schwinger made a quantum electrodynamical calculation that made use of the notions of mass and charge renormalization, which brought agreement between theory and experimental data. This was a crucial breakthrough that initiated a new era in quantum field theory. Richard Feynman and Tomonaga Shin’ichirō independently had carried out similar calculations, and in 1965 the three of them shared the Nobel Prize. Their work created a new and very successful quantum mechanical description of the interaction between electrically charged entities and the electromagnetic field that conformed with the principles of Albert Einstein’s special theory of relativity.

Schwinger’s work extended to almost every frontier of modern theoretical physics. He had a profound influence on physics both directly and through being the academic adviser for more than 70 doctoral students and more than 20 postdoctoral fellows, many of whom became the outstanding theorists of their generation.

Details

Julian Seymour Schwinger (February 12, 1918 – July 16, 1994) was a Nobel Prize-winning American theoretical physicist. He is best known for his work on quantum electrodynamics (QED), in particular for developing a relativistically invariant perturbation theory, and for renormalizing QED to one loop order. Schwinger was a physics professor at several universities.

Schwinger is recognized as an important physicist, responsible for much of modern quantum field theory, including a variational approach, and the equations of motion for quantum fields. He developed the first electroweak model, and the first example of confinement in 1+1 dimensions. He is responsible for the theory of multiple neutrinos, Schwinger terms, and the theory of the spin-3/2 field.

Biography:

Early life and career

Julian Seymour Schwinger was born in New York City, to Ashkenazi Jewish parents, Belle (née Rosenfeld) and Benjamin Schwinger, a garment manufacturer, who had emigrated from Poland to the United States. Both his father and his mother's parents were prosperous clothing manufacturers, although the family business declined after the Wall Street Crash of 1929. The family followed the Orthodox Jewish tradition. Julian's older brother Harold Schwinger was born in 1911, seven years before Julian who was born in 1918.

Schwinger was a precocious student. He attended the Townsend Harris High School from 1932 to 1934, a highly regarded high school for gifted students at the time. During high school, Julian had already started reading Physical Review papers by authors such as Paul Dirac in the library of the City College of New York, in whose campus Townsend Harris was then located.

In the fall of 1934, Schwinger entered the City College of New York as an undergraduate. CCNY automatically accepted all Townsend Harris graduates at the time, and both institutions offered free tuition. Due to his intense interest in physics and mathematics, Julian performed very well in those subjects despite often skipping classes and learning directly from books. On the other hand, his lack of interest for other topics such as English led to academic conflicts with teachers of those subjects.

After Julian had joined CCNY, his brother Harold, who had previously graduated from CCNY, asked his ex-classmate Lloyd Motz to "get to know [Julian]". Lloyd was a CCNY physics instructor and Ph.D. candidate at Columbia University at the time. Lloyd made the acquaintance, and soon recognized Julian's talent. Noticing Schwinger's academic problems, Lloyd decided to ask Isidor Isaac Rabi who he knew at Columbia for help. Rabi also immediately recognized Schwinger's capabilities on their first meeting, and then made arrangements to award Schwinger with a scholarship to study at Columbia. At first Julian's bad grades in some subjects at CCNY prevented the scholarship award. But Rabi persisted and showed an unpublished paper on quantum electrodynamics written by Schwinger to Hans Bethe, who happened to be passing by New York. Bethe's approval of the paper and his reputation in that domain were then enough to secure the scholarship for Julian, who then transferred to Columbia. His academic situation at Columbia was much better than at CCNY. He was accepted into the Phi Beta Kappa society and received his B.A. in 1936.

During Schwinger's graduate studies, Rabi felt that it would be good for Julian to visit other institutions around the country, and Julian was awarded a travelling fellowship for the year 37/38 which he spent at working with Gregory Breit and Eugene Wigner. During this time, Schwinger, who previously had already had the habit of working until late at night, went further and made the day/night switch more complete, working at night and sleeping during the day, a habit he would carry throughout his career. Schwinger later commented that this switch was in part a way to retain greater intellectual independence and avoid being "dominated" by Breit and Wigner by simply reducing the duration of contact with them by working different hours.

Schwinger obtained his PhD overseen by Rabi in 1939 at the age of 21.

During the fall of 1939 Schwinger started working at the University of California, Berkeley under J. Robert Oppenheimer, where he stayed for two years as an NRC fellow.

Career

After having worked with Oppenheimer, Schwinger's first regular academic appointment was at Purdue University in 1941. While on leave from Purdue, he worked at the MIT Radiation Laboratory instead of at the Los Alamos National Laboratory during World War II. He provided theoretical support for the development of radar. After the war, Schwinger left Purdue for Harvard University, where he taught from 1945 to 1974. In 1966 he became the Eugene Higgins professor of physics at Harvard.

Schwinger developed an affinity for Green's functions from his radar work, and he used these methods to formulate quantum field theory in terms of local Green's functions in a relativistically invariant way. This allowed him to calculate unambiguously the first corrections to the electron magnetic moment in quantum electrodynamics. Earlier non-covariant work had arrived at infinite answers, but the extra symmetry in his methods allowed Schwinger to isolate the correct finite corrections.

Schwinger developed renormalization, formulating quantum electrodynamics unambiguously to one-loop order.

In the same era, he introduced non-perturbative methods into quantum field theory, by calculating the rate at which electron–positron pairs are created by tunneling in an electric field, a process now known as the "Schwinger effect." This effect could not be seen in any finite order in perturbation theory.

Schwinger's foundational work on quantum field theory constructed the modern framework of field correlation functions and their equations of motion. His approach started with a quantum action and allowed bosons and fermions to be treated equally for the first time, using a differential form of Grassman integration. He gave elegant proofs for the spin-statistics theorem and the CPT theorem, and noted that the field algebra led to anomalous Schwinger terms in various classical identities, because of short distance singularities. These were foundational results in field theory, instrumental for the proper understanding of anomalies.

In other notable early work, Rarita and Schwinger formulated the abstract Pauli and Fierz theory of the spin-3/2 field in a concrete form, as a vector of Dirac spinors, Rarita–Schwinger equation. In order for the spin-3/2 field to interact consistently, some form of supersymmetry is required, and Schwinger later regretted that he had not followed up on this work far enough to discover supersymmetry.

Schwinger discovered that neutrinos come in multiple varieties, one for the electron and one for the muon. Nowadays there are known to be three light neutrinos; the third is the partner of the tau lepton.

In the 1960s, Schwinger formulated and analyzed what is now known as the Schwinger model, quantum electrodynamics in one space and one time dimension, the first example of a confining theory.

Having supervised 73 doctoral dissertations, Schwinger is known as one of the most prolific graduate advisors in physics. Four of his students won Nobel prizes: Roy Glauber, Benjamin Roy Mottelson, Sheldon Glashow and Walter Kohn (in chemistry).

Schwinger had a mixed relationship with his colleagues, because he always pursued independent research, different from mainstream fashion. In particular, Schwinger developed the source theory, a phenomenological theory for the physics of elementary particles, which is a predecessor of the modern effective field theory. It treats quantum fields as long-distance phenomena and uses auxiliary 'sources' that resemble currents in classical field theories. The source theory is a mathematically consistent field theory with clearly derived phenomenological results. The criticisms by his Harvard colleagues led Schwinger to leave the faculty in 1972 for UCLA. It is a story widely told that Steven Weinberg, who inherited Schwinger's paneled office in Lyman Laboratory, there found a pair of old shoes, with the implied message, "think you can fill these?". Based on Schwinger's source theory, Weinberg set the underpinnings of the effective field theory, that is more appreciated among physicists. In spite of the shoes incident, Weinberg gave the credit to Schwinger for the inspiration.

At UCLA, and for the rest of his career, Schwinger continued to develop the source theory and its various applications. After 1989 Schwinger took a keen interest in the non-mainstream research of cold fusion. He wrote eight theory papers about it. He resigned from the American Physical Society after their refusal to publish his papers. He felt that cold fusion research was being suppressed and academic freedom violated. He wrote, "The pressure for conformity is enormous. I have experienced it in editors' rejection of submitted papers, based on venomous criticism of anonymous referees. The replacement of impartial reviewing by censorship will be the death of science."

In his last publications, Schwinger proposed a theory of sonoluminescence as a long-distance quantum radiative phenomenon associated not with atoms, but with fast-moving surfaces in the collapsing bubble, where there are discontinuities in the dielectric constant. The mechanism of sonoluminescence now supported by experiments focuses on superheated gas inside the bubble as the source of the light.

Schwinger was jointly awarded the Nobel Prize in Physics in 1965 for his work on quantum electrodynamics (QED), along with Richard Feynman and Shin'ichirō Tomonaga. Schwinger's awards and honors were numerous even before his Nobel win. They include the first Albert Einstein Award (1951), the U.S. National Medal of Science (1964), honorary D.Sc. degrees from Purdue University (1961) and Harvard University (1962), and the Nature of Light Award of the U.S. National Academy of Sciences (1949). In 1987, Schwinger received the Golden Plate Award of the American Academy of Achievement.

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