In 1903, Marie Curie became the first woman to win a Nobel Prize (in experimental Physics). It took another sixty years for the second woman to become a Physics Nobel Laureate. That was Maria Goeppert Mayer, the first (and only) woman to win the award for theoretical physics. (It would take another 60+ years for Donna Strickland to become the third woman physics laureate in 2018),
“Science offends the modesty of all real women. It makes them feel as though it were an attempt to peek under their skins—or, worse yet, under their dress and ornamentation!”
– Fredrich Nietzshe, 1886
Like her female colleagues, Dr. Mayer had a tough time getting a paying teaching job. Indeed, after working for free at various universities, including the University of Chicago and Columbia, and barricaded by the same nepotism rule favoring her scientist husband that impeded Dr. Gerti Cory, Dr. Mayer’s first paid full-time position at the University of California, came in 1960 - thirty years after she got her doctorate and three years before she 
won the Nobel Prize, sharing it with a colleague for proposing the nuclear shell structure of atoms.
Women, Too, Stand on the Shoulders of Giants
Born in Germany in 1906, Maria grew up in Göttingen and was known as the prettiest girl in town: slim, blonde, and stylish, with her teachers telling her that girls don’t need to learn math or physics. But being an only child, Maria’s professor father exhorted her to set her sights beyond being a mere housewife.
That she did, first attending a special high school designed to prepare young women for higher education (also attended by Dr. Lise Meitner, the Shoulda-Been Nobel Laureate who co-discovered nuclear fission). [1] After graduating, Maria enrolled in the University of Gottingen to study mathematics, likely meeting up with the school’s sole woman professor, Dr. Emmy Noether, widely regarded as the greatest woman mathematician. But it was physicist Max Born (who would win the Nobel in 1954 for his work on quantum mechanics), a family friend, who became her first mentor as she switched fields from math to physics in 1927.
“Mathematics began to seem too much like puzzle solving. Physics is puzzle solving, too, but of puzzles created by nature, not by the mind of men.” – Maria Goeppert.
That year, she would also meet the man who would become her husband, physical chemist Joseph Mayer, an American who boarded with the Goeppert family while studying quantum mechanics at Gottingen University. In 1930, a year after receiving her doctorate (under Max Born’s tutelage) and marrying Joe, she followed him to the US, where he had secured a teaching post at Johns Hopkins. Thus began her vying for position and recognition, relegated to small offices and non-paid assistantships, a situation lasting for decades even as she co-wrote important papers and books, including with Max Born.
The Atomic Bomb
When Joe migrated from Hopkins to Columbia in 1937 (after being fired because of his dean’s hatred of women, ostensibly provoked by Maria’s presence), Maria followed. The time at Hopkins wasn’t lost, however. There, she met Edward Teller, soon to become her second mentor. Again, at Columbia, no formal position was forthcoming and in 1941, she took a part-time position teaching general science at Sarah Lawrence, which paid a small but tangible salary. Yet, even as the old guard were put off by women in the profession, Maria made a strong impression on the leaders of the new physics, including Teller and future Nobel Laureate Harold Urey.
Taking time off to bear her two children, she co-wrote the classic physics text Statistical Mechanics with Urey. Sadly, without a formal university affiliation, her status as co-author was sorely diminished. With great difficulty, Urey got Maria an unpaid lectureship before recruiting her for her next position in the newly formed Substitute Alloy Materials Group (SAM), which was conducting research for the Manhattan Project, charged with building the atomic bomb. At SAM, Maria was assigned to separating U-235 (the Uranium isotope capable of nuclear fission) from the more plentiful but virtually un-fissionable U-238 (for eventual use in atomic bombs).
While exultant that her work as a scientist was finally taken seriously, Maria was uncomfortable working on a weapon with such monstrous implications. She worried about friends and family in Germany, a country she still loved. And then Joe was sent to inspect weapons at Aberdeen Proving Grounds in Maryland, separating the couple for the next four years. Not being able to discuss her top-secret activities with anyone, even her husband or new friend Laura Fermi (Enrico’s wife), added to the pressure. This, along with her all-consuming interest in her work, resulted in continuing rifts with her children.
But her diligence and dedication to her work resulted in her promotion to Head of the Opacity Project, where she investigated the thermodynamic properties of matter and radiation at high temperatures, under Teller’s direction.
Eventually, the bomb was finished, and Maria and colleagues were out of a job. Urey, Teller, Joe, and Maria were offered jobs at the University of Chicago. Yet again, Maria’s position was unpaid, but she gladly accepted the assistant professorship.
But the pressures were catching up. Maria was now drinking and smoking heavily, and Joe’s eye was said to be roving.
Magic Numbers
Perhaps as a refuge, she threw herself into working with Teller at Argonne National Laboratory, focusing on the origin of elements. Here, she began the work that would lead to her Nobel Prize. Noting that some elements, like tin and lead, were more plentiful than others, she figured this was because they had more stable nuclei, but the puzzle became what made them so stable. (Unstable elements undergo radioactive decay, losing or gaining electrons to form new combinations.)
She soon reasoned that the components of atomic nuclei were structured in layers, similar to electrons forming shells around the nucleus of an atom. These “nucleic” layers, made up of either positively charged protons or neutrons, particles without a charge, fit together tightly. The more tightly packed each layer is, the more stable the element because no new particle could disrupt the layer by insinuating itself. There simply wouldn’t be any room, which translated into a higher nuclear binding energy. [2]
She soon concluded (via mathematical analysis) that the stability of an element depends on the precise number of nucleic particles (nucleons) in each layer, which she calculated for eight shells. The layers follow a precise pattern: two particles in the first layer, six in the second, twelve in the third, and eight in the fourth, etc., [3] whether they are protons or neutrons. Maria called these “magic numbers.”
When both the proton and neutron layers are composed of magic numbers of either nucleon, the element becomes a “doubly magic quantum nucleus,” the most stable of all elements.
Stability in the Nucleus – But Not at Home
In 1959, ten years after publishing her work with Hans Jensen (who independently arrived at the same conclusions), Maria and Joe were offered positions at the University of California. For the first time, she would hold a full professorship in physics along with a corresponding salary. They left Chicago in 1960. The move was tumultuous, and shortly before arriving, Maria would suffer a stroke. But for the first time, she would hold a full professorship in physics along with a corresponding salary. Four years later she would receive the Nobel prize.
She died in 1972, at age 65, estranged from her children but honored by her colleagues, having fulfilled her father’s first admonition:
“Be More Than Just a Woman” – Professor Friedrich Göppert
[1] In High School, Maria played hooky to attend a lecture by physicist and neighbor David Hilbert (who mentored Emmy Noether), which also made an impression.
[2] Due to the direction of both their spin and their orbit, intermingling like the rotating teacup ride at the fair)
[3] The magic numbers are 2, 8, 20, 28, 50, 126, and 184
