The second woman to win the physics Nobel

This week, Donna Strickland became just the third woman to be awarded a Nobel Prize in Physics . The first was Marie Curie , who won in 1903. Curie has become a scientific legend and a household name. But the second female physics Nobelist, Maria Goeppert Mayer, is not nearly as well known. That’s a pity, because her work on nuclear structures was a major breakthrough in atomic physics—an achievement all the more remarkable because she did that work without a permanent scientific job.

Maria Goeppert was born in 1906 in Kattowitz, Prussia. Her father, a professor of pediatrics, encouraged his talented daughter’s interest in mathematics and physics, and in 1930 Goeppert earned a PhD from the University of Göttingen in Germany. Legendary physicist Max Born supervised her doctoral dissertation on photon absorption in atoms.

That same year, Goeppert married Joseph Mayer, an American chemist who was at Göttingen on a Rockefeller Foundation fellowship. She moved with her new husband to Baltimore, Maryland, where he had accepted a job as a professor at Johns Hopkins University. Goeppert Mayer was not offered a permanent appointment at Hopkins—the university had strict anti-nepotism rules. She was, however, permitted to teach graduate students in the physics department and to continue her theoretical work on quantum mechanics in a physics department office, her former student Robert Sachs wrote in a 1982 article for Physics Today .

Joseph Mayer lost his position at Hopkins in 1939 following clashes with administrators. According to biographer Joan Dash, Goeppert Mayer suspected that her presence in the physics department had been partly to blame for her husband’s difficulties; some of those Hopkins administrators had openly expressed disapproval of women scientists. Goeppert Mayer followed her husband to new positions at Columbia University and the University of Chicago. She also contributed to the Manhattan Project groups at Columbia and Los Alamos in the mid 1940s. After the war, she cobbled together a string of temporary appointments, often going entire academic years without a paying post. Her title at the University of Chicago was “voluntary associate professor"—in other words, she was not paid.

Fortunately, as a theoretical physicist, Goeppert Mayer’s lack of laboratory space did not prevent her from continuing her work. Just after World War II ended, she began studying nuclear structures. As physicist Karen Johnson explained in a 1986 Physics Today feature , Goeppert Mayer analyzed data about the abundances of various isotopes and found that a pattern emerged: “It appeared that nuclei with 2, 8, 20, 28, 50, 82, or 126 neutrons or protons were unusually stable.” She posited that the nucleus might contain shells of protons and neutrons that could only hold specific numbers of nucleons, a structure analogous to the electron shells that Niels Bohr had outlined in 1913.

However, as Johnson details, physicists were unsure of the reason why those numbers in particular were most stable. A conversation between Goeppert Mayer and her Chicago colleague Enrico Fermi led her to a crucial insight: Spin–orbit coupling was responsible. In back-to-back papers for Physical Review, published in April 1950, she outlined the consequences of spin–orbit coupling for nuclear modeling. Those papers were published while she was in a temporary post at Argonne National Laboratory—one her former student Sachs, who had become Argonne’s director, had helped her obtain.

In 1960, Goeppert Mayer and her husband were recruited to the University of California, San Diego, where they were both appointed full professors—her first permanent, paid scientific post since earning her doctorate 30 years earlier.

Three years later, Goeppert Mayer shared the 1963 Nobel Prize in Physics with Hans Jensen and Eugene Wigner for work on nuclear shell structures. In his 1972 obituary for Goeppert Mayer, who died of complications from a heart attack at the age of 65, Wigner wrote that his late colleague had contributed to physics “not only by means of original ideas but also by the lucidity of her exposition and the clarity of the articles (and books) she authored.”