(The study of mechanics is presented as the fundamental ba...)
The study of mechanics is presented as the fundamental basis of the electromagnetic theory, quantum mechanics, and all theoretical physics. Mathematical difficulty and order of historical development have determined the order of presenting the material.
John Clarke Slater was a noted American physicist, educator and author who made major contributions to the theory of the electronic structure of atoms, molecules and solids.
Background
John Clarke Slater was born on December 22, 1900, in Oak Park, Illinois, United States. He was the son of John Rothwell and Katharine Southland (Chapin) Slater. His father was head of the English department at the University of Rochester.
In his boyhood, Slater was very much interested in mathematics and in examining such devices as electrical motors and lamps. His father, whose home library included physics classics like A. A. Michelson’s Light Waves and Their Uses strongly encouraged his son’s scientific bent and in later years would habitually enclose clippings from Scientific American in his letters. Slater’s high school interests also included watercolour painting, architecture, and printing in his attic print shop.
Education
Slater enrolled in the University of Rochester in 1917 as an undergraduate student in physics, chemistry, and mathematics.
In 1921 Slater moved to Harvard, where he attended Bridgman’s course in fundamental physics. He was more interested, though, in a course in quantum physics. Within three years, Slater had completed work on his Ph.D. thesis, an experimental study devoted to an examination of the compressibility of the alkali halides. A Harvard Sheldon fellowship enabled him to continue his studies abroad. Slater first visited Cambridge University, where he studied at Cavendish Laboratory. He then also studied at Niels Bohr’s Center for Physical Research in Copenhagen.
As a researcher, Slater received an honorary degree from the University of Rochester in 1964.
In 1924, Slater was invited to join the staff of Harvard’s physics department on his return to the United States. In 1925 he published two important papers. The first was on the correlation of the width of a spectral line with the reciprocal lifetime of a stationary state. The second dealt with the interpretation of the spectra of hydrogen and ionized helium. Despite being geographically isolated from the hotbed of the new quantum mechanics in Europe, Slater kept abreast of developments.
In 1927 Slater produced his first paper on quantum mechanics proper, entitled “Radiation and Absorption on Schrodinger’s Theory.” Here, Slater employed the Austrian physicist Erwin Schroedinger’s idea of atoms as standing waves.
In 1930 on his return from a brief visit to Europe on a Guggenheim fellowship, Slater was appointed a chairman of the Massachusetts Institute of Technology’s physics department. His ambition as a teacher and administrator was to bring American physics education up to par with that in Europe, so that young American physicists would no longer have to make the pilgrimage abroad to finish their education. He directed a member of his department, N. H. Frank, to rework the undergraduate curriculum, and personally rewrote the senior course in theoretical physics. Slater did not neglect graduate training. He reorganized the available programs and the examination system to allow students more time for research.
The upshot of all of this activity was that Slater became, at the age of thirty-one, one of the National Academy’s youngest members. He justified that honour with an interminable output of papers and books. Of the latter, he published fourteen during his lifetime, on subjects ranging from microwaves and chemical physics to quantum theory. His papers examined an assortment of phenomena, including directed valence and the quantum theory of the equation of state (1931); energy bands in metals (1934); ferromagnetism in nickel (1936); the structure of alloys and the superconductive state (1937); and the structure of insulating crystals (1938).
When World War II broke out, Slater joined the staff of the Radiation Laboratory, which had been set up at MIT to develop microwave radar. His resultant book, Microwave Transmission, quickly became the authority in the field. Later in the war, he worked at the Bell Telephone Laboratories in Manhattan. There he undertook theoretical and experimental work on magnetrons, that is, diode vacuum tubes in which the flow of electrons is controlled by an external magnetic field to generate power at microwave frequencies.
After the war, Slater redirected his attention to reshaping MIT’s physics department, particularly, reorienting wartime pursuits to peaceful ends. He was determined to maintain the department’s unique diversity despite the trend toward specialization. He converted the Radiation Laboratory into a research laboratory of electronics, established a laboratory of nuclear science and engineering, and established an acoustics laboratory. Peacetime also enabled him to re-devote himself to his own interests, especially in solid-state and molecular physics. In 1950 he set up a research group called the Solid-State and Molecular Theory Group (SSMTG), a precursor to the Interdepartmental Center for Materials Science and Engineering, which was established ten years later.
The following year, acting on his desire to free himself of his administrative burdens. Slater accepted an invitation to become an institute professor at Brookhaven National Laboratory on Long Island. There, with some members of the SSMTG, he continued his research into the quantum theory of atoms, molecules, and solids using primitive computers. Sixty people were involved with the group during its fifteen-year history. Slater had a hand in almost all of its work. He also produced five books related to the group’s work.
In 1964 Slater had the special pleasure of standing head to head with his father when both were awarded honorary degrees by the University of Rochester. The following year, having reached the retirement age at MIT, Slater accepted the position of research professor at the University of Florida, where the retirement age was seventy. There, he joined the Quantum Theory Project, which had been set up by one of his colleagues from the SSMTG, Per-Olov Lowdin. Until his death on July 25, 1976, Slater led an active professional and personal life.
Quotations:
"This fact, that all charges are integral multiples of a fundamental unit, is still one of the unexplained puzzles of fundamental physics. It does not in any way contradict electromagnetic theory, but it is not predicted by it, and until we have a more fundamental theory that explains it, we shall not feel that we really understand electromagnetic phenomena thoroughly. Presumably its explanation will not come until we understand quantum theory more thoroughly than we do at present."
Membership
Slater was a member of the American Physical Society, American Academy Arts and Sciences, National Academy Sciences, American Philosophical Society, Phi Beta Kappa and Delta Upsilon.
Connections
Slater married Helen Frankenfeld in 1926. Their three children, Louise Chapin, John Frederick, and Clarke Rothwell, all followed academic careers.
Slater was then divorced and in 1954 he married Dr Rose Mooney, a physicist and crystallographer.