T. K. Radha: Rediscovering a Global Scientist

Many articles in this blog express frustration over how women in science, like Rosalind Franklin, were sidelined and disregarded. I’ve been told that some of my writing carries too much rage and negativity. But T.K. Radha’s story is a partial exception—one of collaboration in science, regardless of gender.

Born in Kerala at a time when higher education for women was rare, Radha defied societal expectations to pursue physics. While her sisters were expected to marry early, her family—initially hesitant—eventually supported her education. Excelling in mathematics, she outperformed both her father and brother in academic scores, yet her passion lay in physics. With limited opportunities for women in physics, Presidency College, Madras—the same institution where her father had studied—was her only option. Her mother, wary of sending her daughter to a co-educational institution, resisted the decision, fearing for her safety in a male-dominated environment. It was Radha’s father who ultimately convinced the family, allowing her to follow in his footsteps and carve her own path in the world of physics. 

TK Radha at the summer school in Trieste, Italy, with
Julian Schwinger and Abdus Salam ©Homegrown 

In the 1950s, she joined the University of Madras, for Alladi Ramakrishnan’s (the founder of the Institute of Mathematical Sciences in Chennai) theoretical physics program. At the time, particle physics was virtually unexplored in Chennai, but Ramakrishnan recognized its growing importance. With limited access to international journals—often delayed by months due to sea mail—Radha and her peers relied on visiting scholars from the Tata Institute in Bombay to bring preprints, allowing them to stay updated with global research. To bridge this gap, Ramakrishnan organized a fund where students contributed to invite renowned physicists like Robert Marshak (expert in subatomic particles and weak interactions), Leonard Schiff (proposed satellite experiment to test general relativity), and Donald Glaser (Nobel Laureate in Physics for inventing the bubble chamber) for lectures. These interactions were crucial, providing Radha and her colleagues with direct mentorship, valuable discussions, and access to cutting-edge developments, enabling them to make meaningful contributions to the field. Her doctoral thesis, which included fourteen published papers, explored Feynman propagators and particle interactions—an exceptional feat in Indian theoretical physics.

Her research spanned institutions and countries, reflecting the growing international recognition of her expertise. During this period, she was also on leave from the Institute of Mathematical Sciences in Madras, affiliating with the Institute of Theoretical Physics at Stanford University.  While on leave from the Institute of Mathematical Sciences in Madras, she was affiliated with the Institute of Theoretical Physics at Stanford University. During this time, she worked with N.T. Meister on a study of three-nucleon wave functions, which was published in Physical Review Letters (PRL). Their work exemplified the global nature of scientific research, with Radha based at Stanford and Meister on leave from a research institute in France. At a time when Indian scientists contributed less than 2% to global physics publications, and women made up fewer than 10% of authors, her numerous first-author papers in prestigious journals highlighted both her expertise and the importance of her research.

Her research explored complex theoretical models, often addressing emerging questions in quantum mechanics and nuclear physics, including symmetry violations and fundamental interactions. In one study, she investigated whether the laws of physics work the same way forward and backward in time (time-reversal symmetry). She estimated the possible size of an electric dipole moment (separation of charge within a particle) in a nucleon (a proton or neutron) based on the idea that a certain type of particle, called a W boson, might exist. Her work suggested that if scientists could measure this small effect, it could help test fundamental physics theories about how particles interact.

In June 1965, J. Robert Oppenheimer—the American theoretical physicist often called the "father of the atomic bomb"—extended an invitation to Radha, urging her to join the Institute for Advanced Study (IAS) in Princeton. This recognition underscored her rising prominence in the global physics community. As one of the world’s most elite hubs for theoretical research, the IAS rarely hosted women of color—making Radha’s appointment a groundbreaking milestone, particularly for a scientist from the Global South during an era of stark gender and racial disparities in STEM. There, she teamed up with physicists like Freeman Dyson (known for his work in quantum electrodynamics, nuclear engineering, and astrophysics, among other fields) and Sergio Piero Fubini (one of the pioneers of string theory), gaining exposure to groundbreaking discussions that influenced her approach to high-energy physics. During her time there, She worked on mathematical rules that describe how particles interact with light, refining theoretical predictions for nuclear reactions.

However, after moving to Canada, Radha chose to step away from academia to focus on childcare. Though this shift presented challenges in returning to formal academic positions, she remained actively involved in physics and computation. She was initially appointed to teach quantum electrodynamics at the University of Alberta. Due to financial constraints and institutional policies, she transitioned into computational analysis. She taught herself programming and became a computational analyst, co-authoring papers behind the scenes. Later, she found new ways to contribute—teaching coding to children, supporting palliative care, and earning recognition such as the YMCA Women of Distinction Award.

Radha’s journey through theoretical physics was a testament to quiet brilliance and unyielding resolve. With a change in her surname, much of her scientific legacy slipped into obscurity until archivist Caitlin Rizzo unearthed her story in the Spring 2023 edition of The Institute Letter, piecing together the achievements of one of the earliest women of color at the Institute for Advanced Study.  

T.K. Radha thrived in a world where few women were welcomed, forging collaborations across continents and contributing to fundamental research despite the barriers she faced. Her journey was one of relentless curiosity and a desire to build a life on her own terms. Whether it was late nights filled with equations and the exhilaration of discovery or mentoring the next generation, she demonstrated resilience and adaptability. Radha’s legacy is not merely one of discovery but of resilience, adaptation, and a quiet defiance against the forces that sought to limit her.  

Written by Janaky S., edited by Parvathy Ramachandran @ThinkHer

References:

1.https://homegrown.co.in/homegrown-voices/tk-radha-the-lesser-known-legacy-of-one-of-the-first-indian-woman-in-stem

2.https://www.ias.edu/ideas/rediscovering-one-institutes-first-women-color

3.https://www.ias.edu/news/losing-track-and-finding-traces-institutes-lesser-known-histories

4.Meister, N. T., and T. K. Radha. "Electric Dipole Moment of a Nucleon." Physical Review 135.3B (1964): B769.

5.Mukunda, N., and T. K. Radha. "Equal-time commutators and photoproduction sum rules." Il Nuovo Cimento A (1965-1970) 44.3 (1966): 726-732.