- died May 10, 1829, LondonEnglish physicist.Trained as a physician, he practiced medicine at St. George's Hospital (from 1811 until his death) but spent much of his time on scientific research. He was the first to describe and measure astigmatism (1800–01) and the first to explain colour sensation in terms of retinal structures corresponding to red, green, and violet (1801). He established the principle of interference of light, thus resurrecting the century-old wave theory of light (1801). He explained capillarity independently of Pierre-Simon Laplace. Investigating elasticity, he proposed Young's modulus, a numerical constant that describes the elastic properties of a solid undergoing tension or compression. His other work included measuring the size of molecules and surface tension in liquids. With J.-F. Champollion, he helped decipher the inscriptions on the Rosetta Stone (1813–14).
* * *▪ British physician and physicistborn June 13, 1773, Milverton, Somerset, Englanddied May 10, 1829, LondonEnglish physician and physicist who established the principle of interference of light and thus resurrected the century-old wave theory of light. He was also an Egyptologist who helped decipher the Rosetta Stone (see photograph—>).In 1799 Young set up a medical practice in London. His primary interest was in sense perception, and, while still a medical student, he had discovered the way in which the lens of the eye changes shape to focus on objects at differing distances. He discovered the cause of astigmatism in 1801, the same year he turned to the study of light.By allowing light to pass through two closely set pinholes onto a screen, Young found that the light beams spread apart and overlapped, and, in the area of overlap, bands of bright light alternated with bands of darkness. With this demonstration of the interference of light, Young definitely established the wave nature of light. He used his new wave theory of light to explain the colours (colour) of thin films (such as soap bubbles), and, relating colour to wavelength, he calculated the approximate wavelengths of the seven colours recognized by Newton. In 1817 he proposed that light waves were transverse (vibrating at right angles to the direction of travel), rather than longitudinal (vibrating in the direction of travel) as had long been assumed, and thus explained polarization, the alignment of light waves to vibrate in the same plane.Young's work was disparaged by most English scientists: any opposition to a theory of Newton's was unthinkable. It was only with the work of the French physicists Augustin J. Fresnel and François Arago that Young's wave theory finally achieved acceptance in Europe.Young also studied the problem of colour perception and proposed that there is no need for a separate mechanism in the eye for every colour, it being sufficient to have three—one each for blue, green, and red. Developed later by the German physicist Hermann L.F. von Helmholtz, this theory is known as the Young–Helmholtz three-colour theory.Having become interested in Egyptology, Young began studying the texts of the Rosetta Stone in 1814. After obtaining additional hieroglyphic writings from other sources, he succeeded in providing a nearly accurate translation within a few years and thus contributed heavily to deciphering the ancient Egyptian language.Young also did work on measuring the size of molecules, surface tension in liquids, and on elasticity. He was the first to give the word energy its scientific significance, and Young's modulus, a constant in the mathematical equation describing elasticity, was named in his honour.
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Young,Thomas — Young, Thomas. 1773 1829. British physician, physicist, and Egyptologist who revived the wave theory of light and postulated the three color theory of color vision. He also helped decipher the hieroglyphics on the Rosetta Stone. * * * … Universalium
Young , Thomas — (1773–1829) British physicist, physician, and Egyptologist Young, who was born at Milverton in southwest England, was a child prodigy. He could read with considerable fluency at the age of 2 and by 13 he had a good knowledge of Latin, Greek,… … Scientists
Young, Thomas — (1773–1829) British scholar. He was born at Milverton, Somerset, England, on 13 June 1773. He studied medicine at the University of London and the University of Edinburgh and undertook further studies at the University of Gottingen and… … Ancient Egypt
Young, Thomas — ► (1773 1829) Médico, físico y arqueólogo británico. Realizó investigaciones sobre la visión y descubrió la aptitud del cristalino para adaptarse cambiando la curvatura. * * * (13 jun. 1773, Milverton, Somerset, Inglaterra–10 may. 1829, Londres) … Enciclopedia Universal
YOUNG, THOMAS — physicist, born in Somersetshire, of Quaker parents; studied medicine at home and abroad; renounced Quakerism, and began practice in London in 1800; was next year appointed professor of Natural Philosophy in the Royal Institution, 1802; made… … The Nuttall Encyclopaedia
Юнг Томас / Young, Thomas — (1773 1829). Благодаря своему интересу к зрению, физик Томас Юнг стал видной фигурой в психологии. Он описал и измерил астигматизм глаза. Посредством измерений фокусного расстояния глаза, Юнг показал, что аккомодацию можно объяснить изменяющейся… … Психологическая энциклопедия
Thomas Young (Politiker) — Thomas Young Thomas Lowry Young (* 14. Dezember 1832 in Killyleagh, Irland; † 20. Juli 1888 in Cincinnati, Ohio) war ein US amerikanischer Politiker und von 1877 bis 1878 der 33. Gouverneur von Ohio … Deutsch Wikipedia
Thomas Young — Nacimiento 13 de junio de 1773 Milverton, Somerset, Inglaterra … Wikipedia Español
Thomas Young (Physiker) — Thomas Young Thomas Young (* 13. Juni 1773 in Milverton, Somersetshire; † 10. Mai 1829 in London) war ein englischer Augenarzt und Physiker … Deutsch Wikipedia
Thomas Marsalis — Thomas Lafayette Marsalis (October 4, 1852 ?) was, with John S. Armstrong, the founder of Oak Cliff, and one of the key developers of what is now known as the Dallas area.He was born in Mississippi near New Orleans, Louisiana. The Marsalis family … Wikipedia