Richard Feynman, the namesake of this website, is best known for his involvement in the Manhattan Project, and for inventing Feynman diagrams. Born in New York in 1918, Feynman went on to become one of the most influential theoretical physicists of the 20th century, and received, along with Shin'ichiro Tomonaga and Julian Schwinger, the Nobel Prize in Physics in 1965. Feynman was also part of the Rogers Commission, which was charged with investigating the Challenger Space Shuttle disaster.
Richard Feynman was born in 1918 in Queens, New York, to Jewish parents. His father was a businessman, with a keen interest in science. Feynman had a sister, Joan, nine years younger than him. Joan would become an astrophysicist.
In 1941, Richard Feynman, while studying at Princeton for a master's degree in Physics, was recruited to work on a device intended to be used to enrich uranium, the isotron, by electromagnetically separating the isotopes Uranium-235 and Uranium-238, to achieve a higher concentration of Uranium-235 in the sample. Despite promising signs, the isotron was deemed to not be as efficient as the current device in use, the calutron, and the project was ended.
Feynman was then moved to Los Alamos and worked under Hans Bethe in the Theoretical Division. While Feynman's work was not critical to the project, he was responsible for some important developments, such as inventing, along with Bethe, the Bethe-Feynman formula, used to calculate the yield of a nuclear bomb (total energy released). While most of the formula is available to the public, the coefficient f of the Bethe-Feynman formula is still classified, along with other nuclear secrets, to discourage nuclear proliferation. In addition, Feynman derived equations which were used to calculate how close a mass of radioactive material was to criticality, in order to prevent potentially lethal accidents.
Feynman was then moved to the secret city of Oak Ridge in Tennessee, where he helped develop safety protocols, to prevent death or severe damage to the facilities, setting back progress on the bomb. The primary aim of his safety measures was to prevent criticality incidents, where an uncontrolled nuclear fission reaction begins, leading to severe radiation exposure for all people in the vicinity, and potentially a nuclear explosion. The attempt of trying to avoid criticality incidents was later described by Feynman as 'tickling the dragon's tail". Sadly, on two occasions involving a plutonium core later called the "demon core", physicists were accidentally exposed to high doses of radiation and died, most notably Louis Slotin in 1946. Overall, 24 people died during the Manhattan Project, including a child who fell into the water used to cool the fission rods.
For a short time, Feynman also worked on the hydride bomb, an attempt to make a nuclear weapon using deuterium (an isotope of hydrogen composed of one proton and one neutron). The advantage of the hydride bomb was that it was far cheaper than the conventional nuclear bomb, as both finding and purifying the material was less expensive. However, the hydride bomb proved to be an incredibly complicated problem to solve, and therefore was scrapped, like the isotron.
Arguably Feynman's greatest work was in his development of Quantum Electrodynamics(QED), jointly with Shin'ichiro Tomonaga and Julian Schwinger, for which they received in 1965 the Nobel Prize in Physics. Quantum Electrodynamics concerns all electromagnetic interactions of fundamental particles, such as electrons. While classical theory would describe an interaction between two electrons in terms of the interaction of their electromagnetic fields, and the forces arising from them, QED represents interactions in terms of bosons (such as photons) exchanged between particles, leading to changes in energy and momentum. QED is also valid for representing particle creation and annihilation, unlike previous theories that attempted to describe electromagnetic interactions in a quantum manner, earning Feynman and his compatriots the Nobel Prize.
Feynman diagrams are two-dimensional representations of the interactions between elementary particles, where one axis represents space, and the other represents time. The diagram above shows the emission of a photon by an electron, causing a change in its momentum and therefore direction, and the absorption of the photon by another electron, leading to a similar change in momentum and direction. Interestingly, antimatter particles are shown as moving backwards in time, such that the arrows are placed in the opposite direction as they would be on a regular matter particle.
On January 28th, 1986, the space shuttle Challenger exploded 73 seconds after takeoff. After the explosion, the Rogers Commission was formed, to investigate the accident in order to find the cause of the explosion. Richard Feynman was by this point terminally ill with cancer, and as such did not wish to be part of the committee at first. Feynman was annoyed by what he called NASA's "safety culture", and voiced his concerns in Appendix F of the report, ridiculing the management's "fantastic faith in the machinery", by explaining that according to their assertion that accidents were a 1 in 100,000 likelihood, "one could put a Shuttle up each day for 300 years expecting to only lose one", indicating the sheer inaccuracy of the figures. The Rogers Commission eventually identified the destruction of seals designed to prevent gas from leaking from the motors as the cause of the explosion.
Richard Feynman died in 1988, of liposarcoma, at the age of 69. Due to the aggressive growth of the tumour, his kidneys were irreparably damaged, leading to kidney failure, and death. His work continues to be hugely important to theoretical physics, as the basis of Quantum Electrodynamics. In addition, Richard Feynman popularised physics through media appearances, and through his two semi-autobiographical books, Surely you're joking, Mr Feynman!, and What do you care what other people think? Over 30 years after his death, Richard Feynman still remains one of the most well-known theoretical physicists in popular memory.
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