Chien-Shiung Wu (1912–1997) is often referred to as “the Chinese Marie Curie” even though she conducted most of her research in the US. She is best known for her discovery of the non-conservation of parity for weakly interacting particles – a finding for which she is widely regarded as having been passed over for the 1957 Nobel Prize in Physics. Seven years earlier, though, in a one-page letter to Physical Review, Wu and her graduate student also quietly reported what has come to be understood as the first conclusive evidence of entangled photons. Twenty years later, as quantum foundations research emerged from shadow, Wu revisited her 1949 experiment with a more refined approach. Wu shared the new results with Stuart Freedman, a collaborator of John Clauser. Clauser et al. would rigorously critique Wu’s experiments through at least 1978. In 2022, the Nobel Committee honored Clauser, Alain Aspect, and Anton Zeilinger, each of whom had produced increasingly convincing proof of entanglement beginning in the 1970s. Wu’s foundational work from almost seventy years earlier, however, was not mentioned. This chapter aims to help bring Wu’s entangled photons back into the light.

Ana María Cetto Kramis (born 1946) studied physics at Universidad Nacional Autónoma de México and biophysics at Harvard University. As a faculty member back in Mexico, she spent over half a century delving into the fundamentals of quantum physics, with a singular focus on its stochastic interpretation. In addition to her theoretical work, she founded Latindex and has become a key figure in the open access movement. She has also had a long and influential contribution to international scientific cooperation. Her professional and personal journeys culminate with the dynamization of the International Year of Quantum Science and Technologies 2025, aiming to shed light on her understanding of quantum science and of science as a whole. This chapter is mostly based on an oral history, which is here also revisited as a historiographical methodology from its early use at the origins of the history of quantum physics.

In recent years, Grete Hermann (1901–1984) has been rediscovered as a principal figure in the history and philosophy of quantum physics. In particular, her criticism of Johann von Neumann’s so-called “no hidden variables” proof is a focal point of interest. Did she really find a mistake in this proof? We argue that the whole debate is misleading. It fits too well with the image of a forgotten woman who disproved a result of a mathematical genius, but it is neither historically nor systematically justified. Despite Hermann’s challenging thoughts on quantum physics, her impressive and important achievements were in ethics and politics. We offer a new and broader reading of Hermann’s interpretation of quantum physics and try to build a bridge between her works on quantum physics and ethics. In doing so, we focus on her interpretation of Heisenberg’s cut as a methaphorical device to argue against Leonard Nelson’s theory of free will and for freedom and responsibility as cornerstones of any democratic society.

Forthcoming

Sonja Ashauer (1923–1948) trained as a physicist at the University of São Paulo in Brazil and obtained a PhD in theoretical and mathematical physics from the University of Cambridge, under the guidance of Paul Dirac. Acknowledged as the first Brazilian woman with a physics PhD, her life was brief: She passed away six months after defending her thesis. In her few contributions, she explored the non-physical consequences of classical equations for point electrons, reformulated by Dirac in the late 1930s to address divergence issues in quantum electrodynamics. This chapter traces Ashauer’s journey from São Paulo, where she collaborated with a small and enthusiastic group of young researchers around the Italian–Russian physicist Gleb Wataghin and focused on cosmic ray physics research, to Cambridge, where she found a more secluded research environment.

The chapter illustrates what it meant for Carolyn Beatrice Parker (1917–1966) to be a Black woman physicist in the US during the Jim Crow era. Her father, a physician, and her mother, a teacher, shepherded her into Fisk University, an historically Black college. As a physics major she studied infrared spectroscopy with the Black physicist Elmer Imes, graduating with a BS in 1938. She later attended the University of Michigan, obtaining an MA in physics in 1941. But like many Black women, she spent time before and after graduate school teaching in the K–12 system. In 1943, she became a research physicist at the Aircraft Radio Laboratory in Dayton, Ohio, where she stayed for four years. Although she co-authored a governmental report about her work on signal attenuation in coaxial cables, her name only appeared in the acknowledgments of the ensuing academic publications, thus partly obscuring her contributions. In 1947, Fisk University welcomed Parker on the faculty, but she soon after enrolled in a nuclear physics PhD program at the Massachusetts Institute of Technology. After dropping out, she worked as a laboratory technician until she grew too ill and died a short time later.

American physicist Freda Friedman Salzman (1927–1981) became an active feminist after her faculty position at the University of Massachusetts Boston was not renewed, under the university’s misogynistic anti-nepotism policy. Whereas her long-lasting struggle and eventual reappointment has already been expounded to some extent, her contributions to physics have not been given proper historical consideration. It is easier to learn about Friedman Salzman’s “weight of being a woman” – as she put it – than about her academic work. This chapter remedies that omission by shedding light on one of her key accomplishments. In 1956, Geoffrey Chew and Francis Low established the well-known Chew–Low model to put the understanding of nuclear interactions on a sounder theoretical basis. The model, however, leads to a daunting nonlinear integral equation. Friedman Salzman and her husband managed to solve the integral equation numerically. Stanley Mandelstam soon recognized the achievement of “Salzman and Salzman” (as he wrote) by naming their approach the “Chew–Low–Salzman method.”

Jane Dewey (1900−1976) was the only woman in a group that John Slater described as the lucky generation of US physicists: those born near the beginning of the twentieth century and who spent time in Europe, learning with the leading quantum physicists of the era. After completing a PhD at the Massachusetts Institute of Technology in 1925, Dewey went to Niels Bohr’s Institute for Theoretical Physics in Copenhagen. She worked on the Stark effect in helium, a key test of the recently formulated quantum mechanics. Bohr praised her skills in a fellowship application, and Karl Compton later supported her (unsuccessful) efforts to land a permanent job. Although Dewey did pioneering work in the field of quantum optics, the conditions she encountered made it difficult for her to continue on this research path. Her promising abilities did not translate into a successful academic career as they did for many of the men of the lucky generation. Perhaps she was not lucky enough. Or was luck conditional on being a man? This chapter argues that subtle – yet, structural – gender discriminatory practices contributed to her gradual exclusion from physics research, and ultimately from academia.

Hertha Sponer’s (1894-1968) early years in physics were spent at the center of the quantum revolution. Training as an experimentalist under Debye, then heading the spectroscopy labs in Göttingen uniquely situated her to contribute to the development of quantum theory and the emergence of quantum chemistry, by novel interpretations of hitherto unexplained spectrographic data using quantum mechanics, and suggesting new applications of the theory to atoms and diatomic molecules. Sponer’s name has nevertheless been largely written out of scientific accounts of these years. When mentioned in the context of quantum theory, it is usually as Franck’s “assistant” (incorrect) and second wife – descriptions that obscure her status as a world-renowned scientist who’d contributed importantly to physics and chemistry over a long and illustrious career. Extant accounts of Sponer’s life and work almost exclusively concern her postwar years as a professor at Duke. But by then quantum theory was well established, and her research had pivoted in other directions. This chapter aims to introduce Sponer into the history of early quantum theory, with appropriate attention to her achievements.

John Wheeler (1911−2008), besides being a key figure in twentieth-century physics in his own right, was also an exceptional mentor and a key witness to historical events. Little known is that his first PhD student was a woman, Katharine Way (1902−1995), who notably played an important role in the postwar organization and dissemination of nuclear data. In the 1990s, Wheeler further made the surprising claim that Way’s work while she was his student came very close to anticipating the discovery of nuclear fission. In addition to gathering the few pieces of information about Way’s early work, this chapter provides a contextualization and evaluation of Wheeler’s words by analyzing his peculiar communicative style, which often subtly mixed history, personal experience, and theoretical insights or guiding ideas. To illustrate this, Wheeler’s pages about personalities such as Marie Curie, Lise Meitner, Maria Goeppert Mayer, and Way herself are considered. It emerges how Wheeler’s original viewpoint has to be properly discussed when evaluating his claim about his former student’s work.

Laura M. Chalk (later, Laura Rowles, 1904−1996) was the first woman to complete a PhD in physics at McGill University in Montreal, Canada. Her doctoral research on the quantum phenomenon called the Stark effect, under the supervision of J. Stuart Foster, produced the earliest experimental test of Erwin Schrödinger’s wave mechanics. After a brief stint as a postdoctoral fellow at King’s College London, she chose to return home and dedicate herself to teaching and marriage. This paper aims to fully recover Chalk’s work and explore why the Foster−Chalk experiment was overlooked in physics historiography. It considers the Stark effect’s significance in quantum physics and the impact of gender on her personal trajectory. Shaped by personal choice, systemic discrimination, and acceptance of societal norms, Chalk Rowles’ story highlights the paradoxes faced by women in a culturally disembodied yet male-dominated field, and reflects broader themes of gender and identity in the history of women in physics.