J. Robert Oppenheimer (born Julius Robert Oppenheimer; /ˈɒpənhaɪmər/ OP-ən-hy-mər; April 22, 1904 – February 18, 1967) was an American theoretical physicist and director of the Manhattan Project's Los Alamos Laboratory during World War II. He is often called the "father of the atomic bomb".

Born in New York City, Oppenheimer earned a bachelor of arts degree in chemistry from Harvard University in 1925 and a doctorate in physics from the University of Göttingen in Germany in 1927, where he studied under Max Born. After research at other institutions, he joined the physics department at the University of California, Berkeley, where he became a full professor in 1936. He made significant contributions to theoretical physics, including achievements in quantum mechanics and nuclear physics such as the Born–Oppenheimer approximation for molecular wave functions, work on the theory of electrons and positrons, the Oppenheimer–Phillips process in nuclear fusion, and early work on quantum tunneling. With his students, he also made contributions to the theory of neutron stars and black holes, quantum field theory, and the interactions of cosmic rays.

In 1942, Oppenheimer was recruited to work on the Manhattan Project, and in 1943 he was appointed director of the project's Los Alamos Laboratory in New Mexico, tasked with developing the first nuclear weapons. His leadership and scientific expertise were instrumental in the project's success. On July 16, 1945, he was present at the first test of the atomic bomb, Trinity. In August 1945, the weapons were used against Japan in the bombings of Hiroshima and Nagasaki, the only use of nuclear weapons in an armed conflict.

In 1947, Oppenheimer became the director of the Institute for Advanced Study in Princeton, New Jersey, and chaired the influential General Advisory Committee of the newly created U.S. Atomic Energy Commission. He lobbied for international control of nuclear power to avert nuclear proliferation and a nuclear arms race with the Soviet Union. He opposed the development of the hydrogen bomb during a 1949–1950 governmental debate on the question and subsequently took positions on defense-related issues that provoked the ire of some U.S. government and military factions. During the second Red Scare, Oppenheimer's stances, together with his past associations with the Communist Party USA, led to the revocation of his security clearance following a 1954 security hearing. This effectively ended his access to the government's atomic secrets and thus his career as a nuclear physicist. Stripped also of his direct political influence, Oppenheimer continued to lecture, write, and work in physics. In 1963, he was awarded the Enrico Fermi Award as a gesture of political rehabilitation. He died four years later of throat cancer. In 2022, the federal government vacated the 1954 revocation of Oppenheimer's security clearance.


Adolf Hitler (German: [ˈa:dɔlf ˈhɪtlɐ] ⓘ; 20 April 1889 – 30 April 1945) was an Austrian-born German politician who was the dictator of Germany from 1933 until his suicide in 1945. He rose to power as the leader of the Nazi Party,[a] becoming the chancellor in 1933 and then taking the title of Führer und Reichskanzler in 1934. During his dictatorship, he initiated World War II in Europe by invading Poland on 1 September 1939. He was closely involved in military operations throughout the war and was central to the perpetration of the Holocaust, the genocide of about six million Jews and millions of other victims.

Hitler was born in Braunau am Inn in Austria-Hungary and was raised near Linz. He lived in Vienna later in the first decade of the 1900s before moving to Germany in 1913. He was decorated during his service in the German Army in World War I. In 1919, he joined the German Workers' Party (DAP), the precursor of the Nazi Party, and in 1921 was appointed leader of the Nazi Party. In 1923, he attempted to seize governmental power in a failed coup in Munich and was sentenced to five years in prison, serving just over a year of his sentence. While there, he dictated the first volume of his autobiography and political manifesto Mein Kampf ("My Struggle"). After his early release in 1924, Hitler gained popular support by attacking the Treaty of Versailles and promoting pan-Germanism, anti-Semitism and anti-communism with charismatic oratory and Nazi propaganda. He frequently denounced international capitalism and communism as part of a Jewish conspiracy.

By November 1932, the Nazi Party held the most seats in the Reichstag but did not have a majority. No political parties were able to form a majority coalition in support of a candidate for chancellor. Former chancellor Franz von Papen and other conservative leaders convinced President Paul von Hindenburg to appoint Hitler as chancellor on 30 January 1933. Shortly thereafter, the Reichstag passed the Enabling Act of 1933 which began the process of transforming the Weimar Republic into Nazi Germany, a one-party dictatorship based on the totalitarian and autocratic ideology of Nazism. Upon Hindenburg’s death on 2 August 1934, Hitler succeeded him, becoming simultaneously the head of state and government with absolute power. Hitler sought to eliminate Jews from Germany and establish a New Order to counter what he saw as the injustice of the post-World War I international order dominated by France and the British Empire. His first six years in power resulted in rapid economic recovery from the Great Depression, the abrogation of restrictions imposed on Germany after World War I, and the annexation of territories inhabited by millions of ethnic Germans, which initially gave him significant popular support.

One of Hitler's key goals was Lebensraum (lit. 'living space') for the German people in Eastern Europe, and his aggressive foreign policy is considered the primary cause of World War II in Europe. He directed large-scale rearmament and, on 1 September 1939, invaded Poland, resulting in Britain and France declaring war on Germany. In June 1941, Hitler ordered an invasion of the Soviet Union. In December 1941, he declared war on the United States. By the end of 1941, German forces and the European Axis powers occupied most of Europe and North Africa. These gains were gradually reversed after 1941, and in 1945 the Allied armies defeated the German army. On 29 April 1945, he married his long-term partner, Eva Braun, in the Führerbunker in Berlin. On the following day, the couple committed suicide to avoid capture by the Soviet Red Army. In accordance with Hitler's wishes, their corpses were burned.

The historian and biographer Ian Kershaw describes Hitler as "the embodiment of modern political evil".[3] Under Hitler's leadership and racist ideology, the Nazi regime was responsible for the genocide of about six million Jews and millions of other victims, whom he and his followers deemed Untermenschen (subhumans) or socially undesirable. Hitler and the Nazi regime were also responsible for the killing of an estimated 19.3 million civilians and prisoners of war. In addition, 28.7 million soldiers and civilians died as a result of military action in the European theatre. The number of civilians killed during World War II was unprecedented in warfare, and the casualties constitute the deadliest conflict in history.

The General Dynamics F-16 Fighting Falcon is an American single-engine supersonic multirole fighter aircraft originally developed by General Dynamics for the United States Air Force (USAF). Designed as an air superiority day fighter, it evolved into a successful all-weather multirole aircraft with over 4,600 built since 1976. Although no longer purchased by the U.S. Air Force, improved versions are being built for export. In 1993, General Dynamics sold its aircraft manufacturing business to the Lockheed Corporation, which became part of Lockheed Martin after a 1995 merger with Martin Marietta.

The Fighting Falcon's key features include a frameless bubble canopy for enhanced cockpit visibility, a side-mounted control stick to ease control while maneuvering, an ejection seat reclined 30 degrees from vertical to reduce the effect of g-forces on the pilot, and the first use of a relaxed static stability/fly-by-wire flight control system that helps to make it an agile aircraft. The F-16 has an internal M61 Vulcan cannon and 11 hardpoints.

In addition to active duty in the U.S. Air Force, Air Force Reserve Command, and Air National Guard units, the aircraft is also used by the U.S. Air Force Thunderbirds aerial demonstration team, the US Air Combat Command F-16 Viper Demonstration Team, and as an adversary/aggressor aircraft by the United States Navy. The F-16 has also been procured by the air forces of 25 other nations. As of 2015, it was the world's most common fixed-wing aircraft in military service.