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Alexander Friedmann
Alexander Alexandrovich Friedmann (also spelled Friedman or Fridman; ; ; – September 16, 1925) was a Russian and Soviet physicist and mathematician. He originated the pioneering theory that the universe is expanding, governed by a set of equations he developed known as the Friedmann equations. Early life Alexander Friedmann was born to the composer and ballet dancer Alexander Friedmann (who was a son of a baptized Jewish cantonist) and the pianist Ludmila Ignatievna Voyachek (who was a daughter of the Czech composer Hynek Vojáček). Friedmann was baptized into the Russian Orthodox Church as an infant, and lived much of his life in Saint Petersburg. Friedmann obtained his degree from St. Petersburg State University in 1910, and became a lecturer at Saint Petersburg Mining Institute. From his school days, Friedmann found a lifelong companion in Jacob Tamarkin, who was also a distinguished mathematician. World War I Friedmann fought in World War I on behalf of Imperial R ...
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Saint Petersburg
Saint Petersburg, formerly known as Petrograd and later Leningrad, is the List of cities and towns in Russia by population, second-largest city in Russia after Moscow. It is situated on the Neva, River Neva, at the head of the Gulf of Finland on the Baltic Sea. The city had a population of 5,601,911 residents as of 2021, with more than 6.4 million people living in the Saint Petersburg metropolitan area, metropolitan area. Saint Petersburg is the List of European cities by population within city limits, fourth-most populous city in Europe, the List of cities and towns around the Baltic Sea, most populous city on the Baltic Sea, and the world's List of northernmost items#Cities and settlements, northernmost city of more than 1 million residents. As the former capital of the Russian Empire, and a Ports of the Baltic Sea, historically strategic port, it is governed as a Federal cities of Russia, federal city. The city was founded by Tsar Peter the Great on 27 May 1703 on the s ...
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Cantonist
Cantonists (; more properly: , "military cantonists") were underage sons of conscripts in the Russian Empire. From 1721 on they were educated in special "cantonist schools" () for future military service (the schools were called garrison schools in the 18th century). The cantonist schools and the cantonist system were eventually abolished in 1857, following public and international criticism and the Russian defeat in the Crimean War. Cantonist schools during the 18th and early 19th centuries Cantonist schools were established by the 1721 Tsar Peter the Great's decree, which stipulated that every regiment was required to maintain a school for 50 boys. Their enrollment was increased in 1732, and the term was set from 7 to 15. The curriculum included grammar and arithmetic, and those with a corresponding aptitude were taught artillery, fortification, music and singing, scrivenery, equine veterinary science, or mechanics. Those lacking such talents were taught carpentry, black ...
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Arthur Geoffrey Walker
Arthur Geoffrey Walker FRS FRSE (17 July 1909 in Watford, Hertfordshire, England – 31 March 2001) was a British mathematician and professor of the University of Sheffield who made important contributions to physical cosmology. Although he was an accomplished geometer, he is best remembered today for two important contributions to general relativity, namely, the Robertson-Walker metric and the Fermi–Walker transport. Early life He was born in Watford on 17 July 1909 the son of Arthur John Walker (b.1879), a coach builder, and his wife, Eleanor Joanna Gosling. Walker attended Watford Grammar School for Boys and won a scholarship to Balliol College, Oxford, where he graduated with first class honours in Mathematics. He then studied at Merton College, Oxford. He then went as a postgraduate to University of Edinburgh, studying for his doctorate (PhD) under Professor Edmund Taylor Whittaker. Professor Arthur Stanley Eddington was his external examiner. His exposure to di ...
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Howard Percy Robertson
Howard Percy "Bob" Robertson (January 27, 1903 – August 26, 1961) was an American mathematician and physicist known for contributions related to physical cosmology and the uncertainty principle. He was Professor of Mathematical Physics at the California Institute of Technology and Princeton University. Robertson made important contributions to the mathematics of quantum mechanics, general relativity and differential geometry. Applying relativity to cosmology, he independently developed the concept of an expanding universe. His name is most often associated with the Poynting–Robertson effect, the process by which solar radiation causes a dust mote orbiting a star to lose angular momentum, which he also described in terms of general relativity. During World War II, Robertson served with the National Defense Research Committee (NDRC) and the Office of Scientific Research and Development (OSRD). He served as technical consultant to the Secretary of War, the OSRD Liaison Officer i ...
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Zeitschrift Für Physik
''Zeitschrift für Physik'' (English: ''Journal for Physics'') is a defunct series of German peer-reviewed physics journals established in 1920 by Springer Berlin Heidelberg. The series ended publication in 1997, when it merged with other journals to form the new '' European Physical Journal'' series. It had expanded to four parts over the years. History *''Zeitschrift für Physik'' (1920–1975 ), The first three issues were published as a supplement to '' Verhandlungen der Deutschen Physikalischen Gesellschaft''. The journal split in parts A and B in 1975. :*''Zeitschrift für Physik A'' (1975–1997). The original subtitle was ''Atoms and Nuclei'' (). In 1986, it split into ''Zeitschrift für Physik A: Atomic Nuclei'' () and ''Zeitschrift für Physik D: Atoms, Molecules and Clusters''. ''Zeitschrift für Physik A'' continues as the '' European Physical Journal A''. :*''Zeitschrift für Physik B'' (1975–1997) resulted from the split of ''Zeitschrift für Physik' ...
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Georges Lemaître
Georges Henri Joseph Édouard Lemaître ( ; ; 17 July 1894 – 20 June 1966) was a Belgian Catholic priest, theoretical physicist, and mathematician who made major contributions to cosmology and astrophysics. He was the first to argue that the recession of galaxies is evidence of an expanding universe and to connect the observational Hubble–Lemaître law with the solution to the Einstein field equations in the general theory of relativity for a homogenous and isotropic universe. That work led Lemaître to propose what he called the "hypothesis of the primeval atom", now regarded as the first formulation of the Big Bang theory of the origin of the universe. Lemaître studied engineering, mathematics, physics, and philosophy at the Catholic University of Louvain and was ordained as a priest of the Archdiocese of Mechelen in 1923. His ecclesiastical superior and mentor, Cardinal Désiré-Joseph Mercier, encouraged and supported his scientific work, allowing Lemaître to trave ...
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Belgians
Belgians ( ; ; ) are people identified with the Kingdom of Belgium, a federal state in Western Europe. As Belgium is a multinational state, this connection may be residential, legal, historical, or cultural rather than ethnic. The majority of Belgians, however, belong to two distinct linguistic groups or ''communities'' (; ) native to the country, i.e. its historical regions: Flemings in Flanders, who speak Dutch, West Flemish and Limburgish; and Walloons in Wallonia, who speak French or Walloon. There is also a substantial Belgian diaspora, which has settled primarily in the United States, Canada, France, and the Netherlands. Etymology The 1830 revolution led to the establishment of an independent country under a provisional government and a national congress. The name "Belgium" was adopted for the country, the word being derived from '' Gallia Belgica'', a Roman province in the northernmost part of Gaul that, before Roman invasion in 100 BC, was inhabi ...
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Carl Wilhelm Wirtz
Carl Wilhelm Wirtz (24 August 1876 in Krefeld – 18 February 1939 in Hamburg) was an astronomer who studied astronomy at Bonn University (1895-1898) obtaining his doctorate there after which he spent his time between the Kiel Observatory in Germany and the Observatory of Strasbourg, France. He is known for statistically showing the existence of a redshift-distance correlation for spiral galaxies. Scientific career As already Vesto Slipher in 1912, Wirtz in 1918 observed a systematic redshift of spiral nebulae, which was difficult to interpret in terms of a cosmological model in which the Universe is filled more or less uniformly with stars and nebulae. Wirtz additionally used the equivalent in German of '' K correction''. The term continues to be used in present-day observational cosmology, but Wirtz's observational evidence that the Universe is expanding is not often mentioned. He wrote: In 1922, he wrote a paper where he argued that the observational results sugges ...
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Hubble's Law
Hubble's law, also known as the Hubble–Lemaître law, is the observation in physical cosmology that galaxies are moving away from Earth at speeds proportional to their distance. In other words, the farther a galaxy is from the Earth, the faster it moves away. A galaxy's recessional velocity is typically determined by measuring its redshift, a shift in the frequency of light emitted by the galaxy. The discovery of Hubble's law is attributed to work published by Edwin Hubble in 1929, but the notion of the universe expanding at a calculable rate was first derived from general relativity equations in 1922 by Alexander Friedmann. The Friedmann equations showed the universe might be expanding, and presented the expansion speed if that were the case. Before Hubble, astronomer Carl Wilhelm Wirtz had, in 1922 and 1924, deduced with his own data that galaxies that appeared smaller and dimmer had larger redshifts and thus that more distant galaxies recede faster from the observer. In ...
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Imperial Russia
Imperial is that which relates to an empire, emperor/empress, or imperialism. Imperial or The Imperial may also refer to: Places United States * Imperial, California * Imperial, Missouri * Imperial, Nebraska * Imperial, Pennsylvania * Imperial, Texas * Imperial, West Virginia * Imperial, Virginia * Imperial County, California * Imperial Valley, California * Imperial Beach, California Elsewhere * Imperial (Madrid), an administrative neighborhood in Spain * Imperial, Saskatchewan, a town in Canada Buildings * Imperial Apartments, a building in Brooklyn, New York * Imperial City, Huế, a palace in Huế, Vietnam * Imperial Palace (other) * Imperial Towers, a group of lighthouses on Lake Huron, Canada * The Imperial (Mumbai), a skyscraper apartment complex in India * Imperial War Museum, a British military museum and organisation based in London, UK * * Imperial War Museum Duxford, an aviation museum in Cambridgeshire, UK * * Imperial War Museum Nort ...
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World War I
World War I or the First World War (28 July 1914 – 11 November 1918), also known as the Great War, was a World war, global conflict between two coalitions: the Allies of World War I, Allies (or Entente) and the Central Powers. Fighting took place mainly in European theatre of World War I, Europe and the Middle Eastern theatre of World War I, Middle East, as well as in parts of African theatre of World War I, Africa and the Asian and Pacific theatre of World War I, Asia-Pacific, and in Europe was characterised by trench warfare; the widespread use of Artillery of World War I, artillery, machine guns, and Chemical weapons in World War I, chemical weapons (gas); and the introductions of Tanks in World War I, tanks and Aviation in World War I, aircraft. World War I was one of the List of wars by death toll, deadliest conflicts in history, resulting in an estimated World War I casualties, 10 million military dead and more than 20 million wounded, plus some 10 million civilian de ...
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Jacob Tamarkin
Jacob David Tamarkin (, ; 11 July 1888 – 18 November 1945) was a Russian-American mathematician, best known for his work in mathematical analysis. Biography Tamarkin was born in Chernigov, Russian Empire (now Chernihiv, Ukraine), to a wealthy Jewish family. His father, David Tamarkin, was a physician and his mother, Sophie Krassilschikov, was from a family of a landowner. He shares a common ancestor with the Van Leer family, sometimes spelled Von Löhr or Valar. He moved to St. Petersburg as a child and grew up there. In high school, he befriended Alexander Friedmann, a future cosmologist, with whom he wrote his first mathematics paper in 1906, and remained friends and colleagues until Friedmann's sudden death in 1925. Vladimir Smirnov was his other friend from the same gymnasium. Many years later, they coauthored a popular textbook titled "A course in higher mathematics". Tamarkin studied in St. Petersburg University where he defended his dissertation in 1917. His advi ...
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