13 Surprising Facts About The Inventor Of The Atomic Bomb

Few scientific breakthroughs in the past century were more pivotal than the discovery of nuclear weapons. What would humanity with the power to level cities in an instant? 

American scientist J. Robert Oppenheimer - brought to the big screen by Christopher Nolan and Cillian Murphy in 2023's self-titled biographical film - helped create the atomic bomb with a group of scientists and was later dubbed the "father of the atomic bomb." The son of a German-born, Jewish immigrant and a Baltimore artist, Oppenheimer's was considered to be a true genius. However, much of his life falls far beyond scientific achievement. Facts about J. Robert Oppenheimer's life show he was not only a brilliant scientist, but a political activist, an educator, and a father.

  • He Supported The Communist Party Before World War II

    During the Great Depression of the 1930s, Oppenheimer became involved in left-wing politics. Specifically, he became very interested in Communism. At the time, the political party was thought to be a reasonable solution for the fascist movements threatening peace in Nazi Germany and throughout Europe.

    Though he never officially joined the Communist Party, the women he courted were staunch supporters and members. His girlfriend and medical school student, Jean Tatlock, introduced Oppenheimer to communist ideals in 1936, placing him in the company of Communist party leaders like Thomas Addis. 

    When his relationship with Tatlock publicly ended in 1939, he fell in love with and married Katherine Puening. His new bride was a former member whose second husband had died in the Spanish Civil War fighting for Spain's left-leaning government. Oppenheimer regularly invited others interested in communism to his home, where they discussed the concept on a philosophical level and exchanged political ideals. While filling out a Manhattan Project security questionnaire, the scientist even joked: 

    [I have] probably belonged to every Communist-front organization on the West Coast.

    As it became increasingly evident that WWII would result in nuclear warfare, the Oppenheimers began distancing themselves from their communist affiliations. While he openly swayed away from the far-left ideals, he continued to secretly keep communist sympathizer Tatlock as a mistress until her passing in 1944. 

    Though he attempted to sever all ties with the party, the association would follow him for the rest of his life.

  • He Knew Several Foreign Languages
    Photo: Unknown author / Wikimedia Commons / Public domain

    He Knew Several Foreign Languages

    Oppenheimer was a natural scholar and enjoyed reading books in their original translation. Over the course of his studies, he learned to speak six different languages outside of his native English: German, Latin, Greek, French, Sanskrit, and Dutch. He used this linguistic advantage to read all three volumes of Karl Marx's Das Kapital in its original German form while taking a three-day train ride to New York, and once revealed that Marcel Proust's A La Recherche du Temps Perdu had pulled him from the depths of a depressive state. 

    The physicist also found solace in the pages of Hindu scripture, the Bhagavad Gita, which he shared in response to witnessing the first atomic testing and the mushroom cloud that filled the sky:

    We knew the world would not be the same. A few people laughed, a few people cried, most people were silent. I remembered the line from the Hindu scripture, the Bhagavad Gita. Vishnu is trying to persuade the Prince that he should do his duty and, to impress him, takes on his multi-armed form and says, ‘Now, I am become Death, the destroyer of worlds.’ I suppose we all thought that one way or another.

  • He Was A Brilliant Teacher And His Students Were Obsessed With Him
    Photo: Lawrence Berkeley National Laboratory / Wikimedia Commons / Public domain

    He Was A Brilliant Teacher And His Students Were Obsessed With Him

    When he wasn't studying physics, Oppenheimer was teaching it. After earning his Ph.D. in quantum physics in Germany, Oppenheimer moved back to the US and split his time teaching between Caltech and the University of California, Berkeley.  

    Oppenheimer developed a following of hundreds of young physicists obsessed with him at these two schools, who became known as the “nim nim boys” after Oppenheimer's habitual humming. The nim nim boys were so enamored with their professor that some of them even copied his wardrobe choices and mannerisms.

    The late physicist Hans Bethe once remarked on Oppenheimer's pedagogical skills

    His lectures were a great experience, for experimental as well as theoretical physicists… In addition to a superb literary style, he brought to them a degree of sophistication in physics previously unknown in the United States. 

    Here was a man who obviously understood all the deep secrets of quantum mechanics, and yet made it clear that the most important questions were unanswered. His earnestness and deep involvement gave his research students the same sense of challenge. He never gave his students the easy and superficial answers but trained them to appreciate and work on the deep problems.

  • Oppenheimer Was Hand-Picked To Lead The Manhattan Project

    In 1938, the US learned German scientists split the atom, thus providing the potential to build weapons that could turn the tide of the war. In retaliation, the US government began recruiting scientists from around the country to build their own weapons in an attempt to beat the Germans. They called the massive undertaking "The Manhattan Project."   

    The construction of the pieces of the atomic weapon was initially dispersed across several universities. However, General Leslie R. Groves was so impressed by Oppenheimer he chose him to oversee the task of assembling those different pieces into one working bomb.  Groves made this choice despite Oppenheimer being a well-known Communist sympathizer, which was typically an instant red flag for security clearance.  Groves more than once ignored security concerns as he thought Oppenheimer was essential to the task and eventually convinced the other project leaders to hire him. This role earned him the title "Father of the Atomic Bomb" and turned him into a national icon almost overnight.

    The Manhattan Project's chief of security, John Lansdale, once noted: 

    I became convinced that not only was he loyal, but that he would let nothing interfere with the successful accomplishment of his task and thus his place in scientific history.

  • He Named The First Testing Of The Atomic Bomb After His Deceased Mistress

    Jean Tatlock and Robert Oppenheimer met in California in 1936 and had an affair that would continue even after Oppenheimer married Katherine Puening in 1940. When they met, she was an active Communist and introduced Oppenheimer to many people associated with the party. 

    In 1943 Oppenheimer, who was already under intense observation by US officials, went on an overnight visit to Tatlock's, causing a major security incident. He was interrogated, and many years later, the visit would cause Oppenheimer to have his security clearance revoked.

    In 1944, Tatlock suffered from a drug overdose and passed away in her apartment. She left behind an unsigned note explaining her choice to end her life, but many, including Tatlock's brother, believe she was targeted by US intelligence agencies. 

    Oppenheimer later used the code name "Trinity" for the first nuclear weapon test in 1945. Most believe that it was named in tribute to Tatlock, who loved the poet John Donne, author of the poem "Trinity."

  • Oppenheimer Is Considered A Founding Father Of American Theoretical Physics
    Photo: US Govt. Defense Threat Reduction Agency / Wikimedia Commons / Public domain

    Oppenheimer Is Considered A Founding Father Of American Theoretical Physics

    As the "Father of the Atomic Bomb," Oppenheimer was so influential in the science community he helped father American theoretical physics. While studying for his Ph.D. in Germany, Oppenheimer and his professor Max Born developed the Born-Oppenheimer Approximation, which outlined "separating nuclear motion from electronic motion in the mathematical treatment of molecules."

    When Oppenheimer returned to America, he was already known in the science community for his work in theoretical physics, and he would go on to make contributions in astrophysics, nuclear physics, spectroscopy, quantum field theory, cosmic ray showers, and work that led to a description of quantum tunneling.