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Eduard Helly
Eduard Helly (June 1, 1884 in Vienna – 28 November 1943 in Chicago) was a mathematician after whom Helly's theorem, Helly families, Helly's selection theorem, Helly metric, and the Helly–Bray theorem were named. Life Helly earned his doctorate from the University of Vienna in 1907, with two advisors, Wilhelm Wirtinger and Franz Mertens. He then continued his studies for another year at the University of Göttingen. Richard Courant, also studying there at the same time, tells a story of Helly disrupting one of Courant's talks, which fortunately did not prevent David Hilbert from eventually hiring Courant as an assistant. After returning to Vienna, Helly worked as a tutor, Gymnasium teacher, and textbook editor until World War I, when he enlisted in the Austrian army. He was shot in 1915, and spent the rest of the war as a prisoner of the Russians. In one prison camp in Berezovka, Siberia, he organized a mathematical seminar in which Tibor Radó, then an engineer, began his int ...
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Vienna
en, Viennese , iso_code = AT-9 , registration_plate = W , postal_code_type = Postal code , postal_code = , timezone = CET , utc_offset = +1 , timezone_DST = CEST , utc_offset_DST = +2 , blank_name = Vehicle registration , blank_info = W , blank1_name = GDP , blank1_info = € 96.5 billion (2020) , blank2_name = GDP per capita , blank2_info = € 50,400 (2020) , blank_name_sec1 = HDI (2019) , blank_info_sec1 = 0.947 · 1st of 9 , blank3_name = Seats in the Federal Council , blank3_info = , blank_name_sec2 = GeoTLD , blank_info_sec2 = .wien , website = , footnotes = , image_blank_emblem = Wien logo.svg , blank_emblem_size = Vienna ( ; german: Wien ; ba ...
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World War I
World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fighting occurring throughout Europe, the Middle East, Africa, the Pacific, and parts of Asia. An estimated 9 million soldiers were killed in combat, plus another 23 million wounded, while 5 million civilians died as a result of military action, hunger, and disease. Millions more died in genocides within the Ottoman Empire and in the 1918 influenza pandemic, which was exacerbated by the movement of combatants during the war. Prior to 1914, the European great powers were divided between the Triple Entente (comprising France, Russia, and Britain) and the Triple Alliance (containing Germany, Austria-Hungary, and Italy). Tensions in the Balkans came to a head on 28 June 1914, following the assassination of Archduke Franz Ferdin ...
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Stefan Banach
Stefan Banach ( ; 30 March 1892 – 31 August 1945) was a Polish mathematician who is generally considered one of the 20th century's most important and influential mathematicians. He was the founder of modern functional analysis, and an original member of the Lwów School of Mathematics. His major work was the 1932 book, ''Théorie des opérations linéaires'' (Theory of Linear Operations), the first monograph on the general theory of functional analysis. Born in Kraków to a family of Goral descent, Banach showed a keen interest in mathematics and engaged in solving mathematical problems during school recess. After completing his secondary education, he befriended Hugo Steinhaus, with whom he established the Polish Mathematical Society in 1919 and later published the scientific journal '' Studia Mathematica''. In 1920, he received an assistantship at the Lwów Polytechnic, subsequently becoming a professor in 1922 and a member of the Polish Academy of Learning in 1924. Banach ...
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Hans Hahn (mathematician)
Hans Hahn (; 27 September 1879 – 24 July 1934) was an Austrian mathematician and philosopher who made contributions to functional analysis, topology, set theory, the calculus of variations, real analysis, and order theory. In philosophy he was among the main logical positivists of the Vienna Circle. Biography Born in Vienna as the son of a higher government official of the k.k. Telegraphen-Korrespondenz Bureau (since 1946 named "Austria Presse Agentur"), in 1898 Hahn became a student at the Universität Wien starting with a study of law. In 1899 he switched over to mathematics and spent some time at the universities of Strasbourg, Munich and Göttingen. In 1902 he took his Ph.D. in Vienna, on the subject "Zur Theorie der zweiten Variation einfacher Integrale". He was a student of Gustav von Escherich. He was appointed to the teaching staff (Habilitation) in Vienna in 1905. After 1905/1906 as a stand-in for Otto Stolz at Innsbruck and some further years as a Privatdozent in Vi ...
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Hahn–Banach Theorem
The Hahn–Banach theorem is a central tool in functional analysis. It allows the extension of bounded linear functionals defined on a subspace of some vector space to the whole space, and it also shows that there are "enough" continuous linear functionals defined on every normed vector space to make the study of the dual space "interesting". Another version of the Hahn–Banach theorem is known as the Hahn–Banach separation theorem or the hyperplane separation theorem, and has numerous uses in convex geometry. History The theorem is named for the mathematicians Hans Hahn and Stefan Banach, who proved it independently in the late 1920s. The special case of the theorem for the space C[a, b] of continuous functions on an interval was proved earlier (in 1912) by Eduard Helly, and a more general extension theorem, the M. Riesz extension theorem, from which the Hahn–Banach theorem can be derived, was proved in 1923 by Marcel Riesz. The first Hahn–Banach theorem was proved by ...
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Heart Attack
A myocardial infarction (MI), commonly known as a heart attack, occurs when blood flow decreases or stops to the coronary artery of the heart, causing damage to the heart muscle. The most common symptom is chest pain or discomfort which may travel into the shoulder, arm, back, neck or jaw. Often it occurs in the center or left side of the chest and lasts for more than a few minutes. The discomfort may occasionally feel like heartburn. Other symptoms may include shortness of breath, nausea, feeling faint, a cold sweat or feeling tired. About 30% of people have atypical symptoms. Women more often present without chest pain and instead have neck pain, arm pain or feel tired. Among those over 75 years old, about 5% have had an MI with little or no history of symptoms. An MI may cause heart failure, an irregular heartbeat, cardiogenic shock or cardiac arrest. Most MIs occur due to coronary artery disease. Risk factors include high blood pressure, smoking, diabetes, lack of e ...
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Signal Corps (United States Army)
) , colors = Orange and white , colors_label = Corps colors , march = , mascot = , equipment = , equipment_label = , battles = , anniversaries = 21 June 1860 , decorations = , battle_honours = , notable_commanders = BG Albert J. Myer BG Adolphus Greely , identification_symbol = , identification_symbol_label = Branch insignia , identification_symbol_2 = , identification_symbol_2_label = Regimental insignia , current_commander = , current_commander_label = , ceremonial_chief = Colonel Paul D. Howard , ceremonial_chief_label = Chief of Signal , command_sergeant_major = CSM Darien D. Lawshea , command_sergeant_major_label = Sergeant Major of the Regiment The United States Army Signal Corps (U ...
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Albert Einstein
Albert Einstein ( ; ; 14 March 1879 – 18 April 1955) was a German-born theoretical physicist, widely acknowledged to be one of the greatest and most influential physicists of all time. Einstein is best known for developing the theory of relativity, but he also made important contributions to the development of the theory of quantum mechanics. Relativity and quantum mechanics are the two pillars of modern physics. His mass–energy equivalence formula , which arises from relativity theory, has been dubbed "the world's most famous equation". His work is also known for its influence on the philosophy of science. He received the 1921 Nobel Prize in Physics "for his services to theoretical physics, and especially for his discovery of the law of the photoelectric effect", a pivotal step in the development of quantum theory. His intellectual achievements and originality resulted in "Einstein" becoming synonymous with "genius". In 1905, a year sometimes described as his ' ...
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Habilitation
Habilitation is the highest university degree, or the procedure by which it is achieved, in many European countries. The candidate fulfills a university's set criteria of excellence in research, teaching and further education, usually including a dissertation. The degree, abbreviated "Dr. habil." (Doctor habilitatus) or "PD" (for "Privatdozent"), is a qualification for professorship in those countries. The conferral is usually accompanied by a lecture to a colloquium as well as a public inaugural lecture. History and etymology The term ''habilitation'' is derived from the Medieval Latin , meaning "to make suitable, to fit", from Classical Latin "fit, proper, skillful". The degree developed in Germany in the seventeenth century (). Initially, habilitation was synonymous with "doctoral qualification". The term became synonymous with "post-doctoral qualification" in Germany in the 19th century "when holding a doctorate seemed no longer sufficient to guarantee a proficient transfer o ...
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Die Zeit
''Die Zeit'' (, "The Time") is a German national weekly newspaper published in Hamburg in Germany. The newspaper is generally considered to be among the German newspapers of record and is known for its long and extensive articles. History The first edition of ''Die Zeit'' was first published in Hamburg on 21 February 1946. The founding publishers were Gerd Bucerius, Lovis H. Lorenz, Richard Tüngel and Ewald Schmidt di Simoni. Another important founder was Marion Gräfin Dönhoff, who joined as an editor in 1946. She became publisher of ''Die Zeit'' from 1972 until her death in 2002, together from 1983 onwards with former German chancellor Helmut Schmidt, later joined by Josef Joffe and former German federal secretary of culture Michael Naumann. The paper's publishing house, Zeitverlag Gerd Bucerius in Hamburg, is owned by the Georg von Holtzbrinck Publishing Group and Dieter von Holtzbrinck Media. The paper is published weekly on Thursdays. As of 2018, ''Die Zeit'' has ...
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Functional Analysis
Functional analysis is a branch of mathematical analysis, the core of which is formed by the study of vector spaces endowed with some kind of limit-related structure (e.g. Inner product space#Definition, inner product, Norm (mathematics)#Definition, norm, Topological space#Definition, topology, etc.) and the linear transformation, linear functions defined on these spaces and respecting these structures in a suitable sense. The historical roots of functional analysis lie in the study of function space, spaces of functions and the formulation of properties of transformations of functions such as the Fourier transform as transformations defining continuous function, continuous, unitary operator, unitary etc. operators between function spaces. This point of view turned out to be particularly useful for the study of differential equations, differential and integral equations. The usage of the word ''functional (mathematics), functional'' as a noun goes back to the calculus of variati ...
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Ussuriysk
Ussuriysk (russian: Уссури́йск) is a types of inhabited localities in Russia, city in Primorsky Krai, Russia, located in the fertile valley of the Razdolnaya River, north of Vladivostok, the administrative center of the krai, and about from both the China–Russia border and the Pacific Ocean. Population: It was previously known as ''Nikolskoye'' (until 1898), ''Nikolsk-Ussuriysky'' (until 1935), ''Voroshilov'' (until 1957). History Medieval history The area of what now is Ussuriysk was settled by Yulou Mohe people, Mohe tribes. From the mid-9th century, it became Solbin-bu of the Balhae Kingdom. It is then populated by the Dōnghǎi Jurchen people, Jurchens, under control of Liao dynasty. The city then become capital of Jīn Dynasty's Sùpín circuit (速頻路). Then it went under control of Yuan, Ming and Qing dynasties respectively and known as (). Modern era In 1866, the settlement of Nikolskoye () was founded on the area of today's Ussuriysk, named after ...
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