Karl Wilhelm Feuerbach
Karl Wilhelm Feuerbach (30 May 1800 – 12 March 1834) was a German geometer and the son of legal scholar Paul Johann Anselm Ritter von Feuerbach, and the brother of philosopher Ludwig Feuerbach. After receiving his doctorate at age 22, he became a professor of mathematics at the Gymnasium at Erlangen. In 1822 he wrote a small book on mathematics noted mainly for a theorem on the nine-point circle, which is now known as Feuerbach's theorem. In 1827 he introduced homogeneous coordinates In mathematics, homogeneous coordinates or projective coordinates, introduced by August Ferdinand Möbius in his 1827 work , are a system of coordinates used in projective geometry, just as Cartesian coordinates are used in Euclidean geometry. ..., independently of Möbius. Works * . ("Properties of some special points in the plane of a triangle, and various lines and figures determined by these points: an analytic-trigonometric treatment") *''Grundriss zu analytischen Untersuchungen d ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Jena
Jena () is a German city and the second largest city in Thuringia. Together with the nearby cities of Erfurt and Weimar, it forms the central metropolitan area of Thuringia with approximately 500,000 inhabitants, while the city itself has a population of about 110,000. Jena is a centre of education and research; the Friedrich Schiller University was founded in 1558 and had 18,000 students in 2017 and the Ernst-Abbe-Fachhochschule Jena counts another 5,000 students. Furthermore, there are many institutes of the leading German research societies. Jena was first mentioned in 1182 and stayed a small town until the 19th century, when industry developed. For most of the 20th century, Jena was a world centre of the optical industry around companies such as Carl Zeiss, Schott and Jenoptik (since 1990). As one of only a few medium-sized cities in Germany, it has some high-rise buildings in the city centre, such as the JenTower. These also have their origin in the former Carl Zeiss factor ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Gymnasium (school)
''Gymnasium'' (and variations of the word) is a term in various European languages for a secondary school that prepares students for higher education at a university. It is comparable to the US English term '' preparatory high school''. Before the 20th century, the gymnasium system was a widespread feature of educational systems throughout many European countries. The word (), from Greek () 'naked' or 'nude', was first used in Ancient Greece, in the sense of a place for both physical and intellectual education of young men. The latter meaning of a place of intellectual education persisted in many European languages (including Albanian, Bulgarian, Estonian, Greek, German, Hungarian, the Scandinavian languages, Dutch, Polish, Czech, Serbo-Croatian, Macedonian, Slovak, Slovenian and Russian), whereas in other languages, like English (''gymnasium'', ''gym'') and Spanish (''gimnasio''), the former meaning of a place for physical education was retained. School structure Be ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
German Lutherans
The religion of Protestantism, a form of Christianity, was founded within Germany in the 16th-century Reformation. It was formed as a new direction from some Roman Catholic principles. It was led initially by Martin Luther and later by John Calvin. History The Protestant Reformation began with the publication of the ''Ninety-five Theses'' by Augustinian monk Martin Luther in 1517. The key element of this religious upheaval was a break from Roman Catholicism's emphasis on tradition, favouring a focus on the Bible. The lasting effects of Luther's Protestant movement within Germany was to question its existing power structures, imploring lay nobles for church reformation, critiquing the Roman mass, sacraments and seeking to reaffirm the importance of faith in good works. His subsequent excommunication from the Church ensured Germany had an ideological divide between Protestant sects and other Christian denominations. Another prominent reformer, Martin Bucer, introduced the rite ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
People From Saxe-Weimar
A person ( : people) is a being that has certain capacities or attributes such as reason, morality, consciousness or self-consciousness, and being a part of a culturally established form of social relations such as kinship, ownership of property, or legal responsibility. The defining features of personhood and, consequently, what makes a person count as a person, differ widely among cultures and contexts. In addition to the question of personhood, of what makes a being count as a person to begin with, there are further questions about personal identity and self: both about what makes any particular person that particular person instead of another, and about what makes a person at one time the same person as they were or will be at another time despite any intervening changes. The plural form "people" is often used to refer to an entire nation or ethnic group (as in "a people"), and this was the original meaning of the word; it subsequently acquired its use as a plural form of per ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Writers From Jena
A writer is a person who uses written words in different writing styles and techniques to communicate ideas. Writers produce different forms of literary art and creative writing such as novels, short stories, books, poetry, travelogues, plays, screenplays, teleplays, songs, and essays as well as other reports and news articles that may be of interest to the general public. Writers' texts are published across a wide range of media. Skilled writers who are able to use language to express ideas well, often contribute significantly to the cultural content of a society. The term "writer" is also used elsewhere in the arts and music, such as songwriter or a screenwriter, but also a stand-alone "writer" typically refers to the creation of written language. Some writers work from an oral tradition. Writers can produce material across a number of genres, fictional or non-fictional. Other writers use multiple media such as graphics or illustration to enhance the communication of thei ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
1834 Deaths
Events January–March * January – The Wilmington and Raleigh Railroad is chartered in Wilmington, North Carolina. * January 1 – Zollverein (Germany): Customs charges are abolished at borders within its member states. * January 3 – The government of Mexico imprisons Stephen F. Austin in Mexico City. * February 13 – Robert Owen organizes the Grand National Consolidated Trades Union in the United Kingdom. * March 6 – York, Upper Canada, is incorporated as Toronto. * March 11 – The United States Survey of the Coast is transferred to the Department of the Navy. * March 14 – John Herschel discovers the open cluster of stars now known as NGC 3603, observing from the Cape of Good Hope. * March 28 – Andrew Jackson is censured by the United States Congress (expunged in 1837). April–June * April 10 – The LaLaurie mansion in New Orleans burns, and Madame Marie Delphine LaLaurie flees to France. * April 14 – The Whig Party is officially named by ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
1800 Births
Eighteen or 18 may refer to: * 18 (number), the natural number following 17 and preceding 19 * one of the years 18 BC, AD 18, 1918, 2018 Film, television and entertainment * 18 (film), ''18'' (film), a 1993 Taiwanese experimental film based on the short story ''God's Dice'' * Eighteen (film), ''Eighteen'' (film), a 2005 Canadian dramatic feature film * 18 (British Board of Film Classification), a film rating in the United Kingdom, also used in Ireland by the Irish Film Classification Office * 18 (Dragon Ball), 18 (''Dragon Ball''), a character in the ''Dragon Ball'' franchise * "Eighteen", a 2006 episode of the animated television series ''12 oz. Mouse'' Music Albums * 18 (Moby album), ''18'' (Moby album), 2002 * 18 (Nana Kitade album), ''18'' (Nana Kitade album), 2005 * ''18...'', 2009 debut album by G.E.M. Songs * 18 (5 Seconds of Summer song), "18" (5 Seconds of Summer song), from their 2014 eponymous debut album * 18 (One Direction song), "18" (One Direction song), from the ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
August Ferdinand Möbius
August Ferdinand Möbius (, ; ; 17 November 1790 – 26 September 1868) was a German mathematician and theoretical astronomer. Early life and education Möbius was born in Schulpforta, Electorate of Saxony, and was descended on his mother's side from religious reformer Martin Luther. He was home-schooled until he was 13, when he attended the college in Schulpforta in 1803, and studied there, graduating in 1809. He then enrolled at the University of Leipzig, where he studied astronomy under the mathematician and astronomer Karl Mollweide.August Ferdinand Möbius, The MacTutor History of Mathematics archive History.mcs.st-andrews.ac.uk. Retrieved on 2017-04-26. In 1813, he began to study astronomy under mathematician < ...
[...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Homogeneous Coordinates
In mathematics, homogeneous coordinates or projective coordinates, introduced by August Ferdinand Möbius in his 1827 work , are a system of coordinates used in projective geometry, just as Cartesian coordinates are used in Euclidean geometry. They have the advantage that the coordinates of points, including points at infinity, can be represented using finite coordinates. Formulas involving homogeneous coordinates are often simpler and more symmetric than their Cartesian counterparts. Homogeneous coordinates have a range of applications, including computer graphics and 3D computer vision, where they allow affine transformations and, in general, projective transformations to be easily represented by a matrix. If homogeneous coordinates of a point are multiplied by a non-zero scalar then the resulting coordinates represent the same point. Since homogeneous coordinates are also given to points at infinity, the number of coordinates required to allow this extension is one more than ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Nine-point Circle
In geometry, the nine-point circle is a circle that can be constructed for any given triangle. It is so named because it passes through nine significant concyclic points defined from the triangle. These nine points are: * The midpoint of each side of the triangle * The foot of each altitude * The midpoint of the line segment from each vertex of the triangle to the orthocenter (where the three altitudes meet; these line segments lie on their respective altitudes). The nine-point circle is also known as Feuerbach's circle (after Karl Wilhelm Feuerbach), Euler's circle (after Leonhard Euler), Terquem's circle (after Olry Terquem), the six-points circle, the twelve-points circle, the -point circle, the medioscribed circle, the mid circle or the circum-midcircle. Its center is the nine-point center of the triangle. Nine significant points The diagram above shows the nine significant points of the nine-point circle. Points are the midpoints of the three sides of the triangle ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Mathematics
Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics with the major subdisciplines of number theory, algebra, geometry, and analysis, respectively. There is no general consensus among mathematicians about a common definition for their academic discipline. Most mathematical activity involves the discovery of properties of abstract objects and the use of pure reason to prove them. These objects consist of either abstractions from nature orin modern mathematicsentities that are stipulated to have certain properties, called axioms. A ''proof'' consists of a succession of applications of deductive rules to already established results. These results include previously proved theorems, axioms, andin case of abstraction from naturesome basic properties that are considered true starting points of ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Saxe-Weimar
Saxe-Weimar (german: Sachsen-Weimar) was one of the Saxon duchies held by the Ernestine branch of the Wettin dynasty in present-day Thuringia. The chief town and capital was Weimar. The Weimar branch was the most genealogically senior extant branch of the House of Wettin. History Division of Leipzig In the late 15th century much of what is now Thuringia, including the area around Weimar, was held by the Wettin Electors of Saxony. According to the 1485 Treaty of Leipzig, the Wettin lands had been divided between Elector Ernest of Saxony and his younger brother Albert III, with the western lands in Thuringia together with the electoral dignity going to the Ernestine branch of the family. Ernest's grandson Elector John Frederick I of Saxony forfeited the electoral dignity in the 1547 Capitulation of Wittenberg, after he had joined the revolt of the Lutheran Schmalkaldic League against the Habsburg emperor Charles V, was defeated, captured and banned. Nevertheless, according ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |