Mathematician J. Ernest Wilkins Jr. was a Manhattan Project standout despite racism

The Manhattan Project brought together the finest scientific minds in the United States for one urgent purpose: to build an atomic bomb. That included people who had historically been marginalized, including Black scientists, who achieved greatness in an era of rampant discrimination.

One of those minds was J. Ernest Wilkins Jr., a Black mathematician, nuclear scientist and optics researcher. Barely past his teen years as the Manhattan Project ramped up, he quickly began working with the top physicists of the time on what was perhaps the most consequential physics research project of the century.

Born in Chicago in 1923, Wilkins was a math prodigy. He was one of the youngest students ever admitted to the University of Chicago — at age 13. He earned his Ph.D. at the university by the time he was 19, in 1942. His academic feats were so impressive that newspaper articles proclaimed him a genius.

Soon, Wilkins began working in the university’s Metallurgical Laboratory, where much more was afoot than mundane studies of metals. Researchers there were helping design nuclear reactors to produce the plutonium needed to create an atomic bomb. With physicist Eugene Wigner, Wilkins began laying the theoretical physics groundwork for nuclear reactors.

In a nuclear reactor, energy is released when uranium atoms fission, or split, after being hit by a neutron. Each fission also releases additional neutrons, which bounce around within the reactor at a variety of energies. Wigner and Wilkins’ work on determining the energy distribution of such neutrons is a foundation of nuclear physics, still cited by researchers today. Those neutrons go on to initiate more fissions, producing a chain reaction, so understanding their energies is crucial for designing reactors.

But in 1944, when Wilkins’ colleagues were scheduled to move to a Manhattan Project site in Oak Ridge, Tenn., Wilkins stayed behind. The state’s racist laws enforcing segregation in businesses, schools and workplaces would have meant unbearable indignities for the young man. “It’s not that he couldn’t go. He refused to go,” says Ronald Mickens, a scientist and colleague of Wilkins during his later years at Clark Atlanta University in Georgia. “He would not allow, and certainly his family would not allow him to live in segregated quarters.”

Still, Wilkins’ skills were in high demand during the Manhattan Project. In 1944, physicist Edward Teller, who later became known as the father of the hydrogen bomb, noted that “[M]en of high qualifications are scarce these days,” and recommended Wilkins to Harold Urey of Columbia University, saying that he “has been doing, according to Wigner, excellent work.”

Wilkins, however, stayed at the University of Chicago until 1946. He signed the Szilard Petition, a letter from 70 scientists to President Harry Truman after the defeat of Germany in World War II, which urged that Japan be given an opportunity to surrender before any atomic bombs were used. The petition never reached Truman.

Wilkins remained a prominent figure in the nuclear physics community throughout his career, serving as president of the American Nuclear Society in 1974–75. According to a 1974 profile in Nuclear News, Wilkins was known for “his quick intelligence, … his directness and good nature.” He delved deeply into complex topics related to nuclear reactors, including how gamma rays, a type of radiation produced in reactors, penetrate through materials.