He chose to go to the University of Cambridge's Cavendish Laboratory in England, where he studied the scattering and absorption of gamma rays.

He used X-rays to investigate ferromagnetism, concluding that it was a result of the alignment of electron spins, and studied cosmic rays, discovering that they were made principally of positively charged particles.

During World War II, Compton was a key figure in the Manhattan Project that developed the first nuclear weapons.

During his tenure, the university formally desegregated its undergraduate divisions, named its first female full professor, and enrolled a record number of students after wartime veterans returned to the United States.

Arthur's eldest brother, Karl, who also attended Wooster, earned a Doctor of Philosophy (PhD) degree in physics from Princeton University in 1912, and was president of the Massachusetts Institute of Technology from 1930 to 1948.

[6] Around 1913, he described an experiment where an examination of the motion of water in a circular tube demonstrated the rotation of the earth, a device now known as the Compton generator.

[8] Compton then studied for his PhD in physics under the supervision of Hereward L. Cooke, writing his dissertation on The Intensity of X-Ray Reflection, and the Distribution of the Electrons in Atoms.

[4] Their sister Mary married a missionary, C. Herbert Rice, who became the principal of Forman Christian College in Lahore.

[10] In 1919, Compton was awarded one of the first two National Research Council Fellowships that allowed students to study abroad.

[12][13] Compton was greatly impressed by the Cavendish scientists, especially Ernest Rutherford, Charles Galton Darwin and Arthur Eddington, and he ultimately named his second son after J. J.

[17][18] In 1923, Compton published a paper in the Physical Review that explained the X-ray shift by attributing particle-like momentum to photons, something Einstein had invoked for his 1905 Nobel Prize–winning explanation of the photo-electric effect.

[20] He found that some X-rays experienced no wavelength shift despite being scattered through large angles; in each of these cases the photon failed to eject an electron.

[18] "When I presented my results at a meeting of the American Physical Society in 1923", Compton later recalled, "it initiated the most hotly contested scientific controversy that I have ever known.

Compton and Alfred W. Simon developed the method for observing at the same instant individual scattered X-ray photons and the recoil electrons.

[17] In 1925, he demonstrated that the scattering of 130,000-volt X-rays from the first sixteen elements in the periodic table (hydrogen through sulfur) were polarized, a result predicted by J. J. Thomson.

Their presence could be detected using a spherical "bomb" containing compressed air or argon gas and measuring its electrical conductivity.

Trips to Europe, India, Mexico, Peru and Australia gave Compton the opportunity to measure cosmic rays at different altitudes and latitudes.

His report, submitted in November, stated that a bomb was feasible, although he was more conservative about its destructive power than Mark Oliphant and his British colleagues.

[30] In June 1942, the United States Army Corps of Engineers assumed control of the nuclear weapons program and Compton's Metallurgical Laboratory became part of the Manhattan Project.

[33] When labor disputes delayed construction of the Metallurgical Laboratory's new home in the Argonne Forest preserve, Compton decided to build Chicago Pile-1, the first nuclear reactor, under the stands at Stagg Field.

[35] Compton arranged for Mallinckrodt to undertake the purification of uranium ore,[36] and with DuPont to build the plutonium semi-works at Oak Ridge, Tennessee.

Oppenheimer's Los Alamos Laboratory met the challenge by designing and building an implosion-type nuclear weapon.

The first batch of uranium slugs was fed into Reactor B at Hanford in November 1944, and shipments of plutonium to Los Alamos began in February 1945.

In 1945, he served, along with Lawrence, Oppenheimer, and Fermi, on the Scientific Panel that recommended military use of the atomic bomb against Japan.

[40] During Compton's time as chancellor, the university formally desegregated its undergraduate divisions in 1952, named its first female full professor, and enrolled record numbers of students as wartime veterans returned to the United States.

Despite Compton's accomplishments, he was criticized then, and subsequently by historians, for moving too slowly toward full racial integration, making Washington University the last major institution of higher learning in St. Louis to open its doors to African Americans.

In his somewhat bizarre mechanism, he imagined sticks of dynamite attached to his amplifier, anticipating the Schrödinger's cat paradox, which was published in 1935.

When one exercises freedom, by his act of choice he is himself adding a factor not supplied by the physical conditions and is thus himself determining what will occur.

[54] Compton invented a more gentle, elongated, and ramped version of the speed bump called the "Holly hump", many of which are on the roads of the Washington University campus.