He then entered the University of California, Berkeley,[1] where he earned his Doctor of Philosophy (PhD) degree, writing his thesis on "Studies of nuclear isomerism in tellurium, element 43, and zinc",[2] under the supervision of George Ernest Gibson.

[5] On March 28, 1941, Seaborg, physicist Emilio Segrè, and Kennedy demonstrated not only the presence of plutonium, but that it was also fissile, an important distinction that was crucial to the decisions made in directing Manhattan Project research.

There was rivalry between its discoverers, with Wahl and Kennedy's group at Los Alamos competing with Seaborg's in Chicago to produce the best process for purifying the metal.

[9] Kennedy's chemists were able to reduce uranium hydride to uranium-235 metal with 99.96% efficiency, and the metallurgists worked out how to cast and press it into the required shapes.

While the project was a collaborative effort with Glenn T. Seaborg, Edwin McMillan, and Arthur Wahl, Nolan’s portrayal honors the collective endeavor while also crediting Kennedy as the key discoverer, adeptly balancing team dynamics with individual achievement.

In real life, President Harry S. Truman, portrayed by Gary Oldman, awarded Kennedy the Medal for Merit for his contributions.

The Medal for Merit was the highest civilian decoration of the United States, with only four awardees from the Manhattan Project at Los Alamos: J. Robert Oppenheimer, John von Neumann, Enrico Fermi, and Kennedy.

[14][15][16] In 1945, Kennedy was recruited to be a professor at Washington University in St. Louis, which installed him as chairman of the department of chemistry in 1946, a role he continued in until his death.

[1][12] Kennedy brought with him Wahl, Lindsay Helmholz, David Lipkin, Herbert Potratz, and Samuel Weissman, who all served on the faculty at Washington University.