George Paget Thomson

Biography

Sir George Paget Thomson (3 May 1892 – 10 September 1975) was a British experimental physicist best known for showing the wave nature of electrons. He shared the 1937 Nobel Prize in Physics with American physicist Clinton Davisson for this work. Born in Cambridge, Thomson was the son of J. J. Thomson, the famous physicist who won the Nobel Prize in 1906 for discovering the electron. It's one of the biggest ironies in physics that the father proved the electron is a particle while the son showed it behaves as a wave. Both ideas are true in the context of quantum mechanics and together demonstrate wave-particle duality, a fundamental concept in modern physics.

Thomson studied at Trinity College, Cambridge, focusing on mathematics and natural sciences. After graduating, he worked with his father at the Cavendish Laboratory, but his academic career was paused by the First World War. He joined the British Army and later the Royal Flying Corps, gaining experience in aerodynamics that influenced some of his later scientific work. After the war, he returned to Cambridge, finished his early research, and then became a professor at the University of Aberdeen. There he conducted the electron diffraction experiments that gained him international fame.

At Aberdeen in 1927, Thomson directed beams of electrons through thin metal films and saw diffraction patterns on photographic plates. These patterns could only be understood if electrons had wave properties. This result confirmed Louis de Broglie's 1924 idea that matter has a wavelength. Independently, Clinton Davisson and Lester Germer in the US reached similar conclusions through reflection experiments. Thomson moved to Imperial College London in 1930, continued work on nuclear physics and electron diffraction, and later became Master of Corpus Christi College, Cambridge, from 1952 to 1962.

During the Second World War, Thomson led the MAUD Committee, a British scientific group set up in 1940 to explore the possibility of an atomic bomb. The committee's 1941 report found that an atomic bomb was scientifically possible and could be built in time to influence the war. This report was crucial in encouraging the United States to start what became the Manhattan Project. Thomson's role in wartime science policy was strategically important, alongside his well-known achievements in experimental physics.

Throughout his career, Thomson received many honors for his scientific contributions. He was elected a Fellow of the Royal Society, received the Royal Medal in 1949, the Hughes Medal in 1939, the Howard N. Potts Medal in 1932, and the Faraday Medal in 1960, and he gave the Royal Society Bakerian Lecture in 1948. He was knighted. He married Kathleen Buchanan Adam Smith, and they had four children. Thomson died in Cambridge on 10 September 1975, in the same city where he had been born over eighty years earlier.