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Lanczos Differentiator
__NOTOC__ Cornelius (Cornel) Lanczos ( hu, Lánczos Kornél, ; born as Kornél Lőwy, until 1906: ''Löwy (Lőwy) Kornél''; February 2, 1893 – June 25, 1974) was a Hungarian-American and later Hungarian-Irish mathematician and physicist. According to György Marx he was one of The Martians. Biography He was born in Fehérvár (Alba Regia), Fejér County, Kingdom of Hungary to Károly Lőwy and Adél Hahn. Lanczos' Ph.D. thesis (1921) was on relativity theory. He sent his thesis copy to Albert Einstein, and Einstein wrote back, saying: "I studied your paper as far as my present overload allowed. I believe I may say this much: this does involve competent and original brainwork, on the basis of which a doctorate should be obtainable ... I gladly accept the honorable dedication."Barbara Gellai (2010) ''The Intrinsic Nature of Things: the life and science of Cornelius Lanczos'', American Mathematical Society In 1924 he discovered an exact solution of the Einstein field equatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Székesfehérvár
Székesfehérvár (; german: Stuhlweißenburg ), known colloquially as Fehérvár ("white castle"), is a city in central Hungary, and the country's ninth-largest city. It is the regional capital of Central Transdanubia, and the centre of Fejér County and Székesfehérvár District. The area is an important rail and road junction between Lake Balaton and Lake Velence. Székesfehérvár, a royal residence (''székhely''), as capital of the Kingdom of Hungary, held a central role in the Middle Ages. As required by the Doctrine of the Holy Crown, the first kings of Hungary were crowned and buried here. Significant trade routes led to the Balkans and Italy, and to Buda and Vienna. Historically the city has come under Ottoman and Habsburg control, and was known in many languages by translations of " white castle" – hr, Stolni Biograd, german: Stuhlweißenburg, la, Alba Regia, ota, İstolni Belgrad, sr, Stoni Beograd, sk, Stoličný Belehrad. History Pre-Hungarian The place ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lanczos Algorithm
The Lanczos algorithm is an iterative method devised by Cornelius Lanczos that is an adaptation of power iteration, power methods to find the m "most useful" (tending towards extreme highest/lowest) eigenvalues and eigenvectors of an n \times n Hermitian matrix, where m is often but not necessarily much smaller than n . Although computationally efficient in principle, the method as initially formulated was not useful, due to its Numerical stability, numerical instability. In 1970, Ojalvo and Newman showed how to make the method numerically stable and applied it to the solution of very large engineering structures subjected to dynamic loading. This was achieved using a method for purifying the Lanczos vectors (i.e. by repeatedly reorthogonalizing each newly generated vector with all previously generated ones) to any degree of accuracy, which when not performed, produced a series of vectors that were highly contaminated by those associated with the lowest natural frequencies. I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Martians (scientists)
"The Martians" ( hu, "A marslakók") is a term used to refer to a group of prominent Hungarian scientists (mostly, but not exclusively, physicists and mathematicians) of Jewish descent who emigrated from Europe to the United States in the early half of the 20th century.M. Whitman (2012) ''The Martian's Daughter: A Memoir'', University of Michigan Press. Leo Szilard, who jokingly suggested that Hungary was a front for aliens from Mars, used this term. In an answer to the question of why there is no evidence of intelligent life beyond Earth despite the high probability of it existing, Szilárd responded: "They are already here among us they just call themselves Hungarians." This account is featured in György Marx's book ''The Voice of the Martians.'' Men frequently included in the description Paul Erdős, Paul Halmos, Theodore von Kármán, John G. Kemeny, John von Neumann, George Pólya, Leó Szilárd, Edward Teller, and Eugene Wigner are included in ''The Martians'' group. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
György Marx
György Marx (25 May 1927 – 2 December 2002) was a Hungarian physicist, astrophysicist, science historian and professor. He discovered the lepton numbers and established the law of lepton flavor conservation. Life He was the first non-British laureate of the Bragg Medal of the Institute of Physics, in 2001. He received it for his "outstanding contributions to physics education". Death Marx died on the December 2, 2002 in Budapest after a serious illness. On December 18 he was buried at the Farkasréti Cemetery with Reformed ceremony in the presence of his family, friends, disciples, colleagues and fellow scientists. Szilveszter E. Vizi Szilveszter E. Vizi (31 December 1936) is a Hungarian physician, neuroscientist, pharmacologist and university professor who served as President of the Hungarian Academy of Sciences between 2002 and 2008. He issues some of his papers under the ..., neuroscientist and president of the Hungarian Academy of Sciences said the prayer for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physicist
A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate causes of phenomena, and usually frame their understanding in mathematical terms. Physicists work across a wide range of research fields, spanning all length scales: from sub-atomic and particle physics, through biological physics, to cosmological length scales encompassing the universe as a whole. The field generally includes two types of physicists: experimental physicists who specialize in the observation of natural phenomena and the development and analysis of experiments, and theoretical physicists who specialize in mathematical modeling of physical systems to rationalize, explain and predict natural phenomena. Physicists can apply their knowledge towards solving practical problems or to developing new technologies (also known as applie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mathematician
A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change. History One of the earliest known mathematicians were Thales of Miletus (c. 624–c.546 BC); he has been hailed as the first true mathematician and the first known individual to whom a mathematical discovery has been attributed. He is credited with the first use of deductive reasoning applied to geometry, by deriving four corollaries to Thales' Theorem. The number of known mathematicians grew when Pythagoras of Samos (c. 582–c. 507 BC) established the Pythagorean School, whose doctrine it was that mathematics ruled the universe and whose motto was "All is number". It was the Pythagoreans who coined the term "mathematics", and with whom the study of mathematics for its own sake begins. The first woman mathematician recorded by history was Hypati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hungarian Americans
Hungarian Americans ( Hungarian: ''amerikai magyarok'') are Americans of Hungarian descent. The U.S. Census Bureau has estimated that there are approximately 1.396 million Americans of Hungarian descent as of 2018. The total number of people with ethnic Hungarian background is estimated to be around 4 million. The largest concentration is in the Greater Cleveland Metropolitan Area in Northeast Ohio. At one time, the presence of Hungarians within Cleveland proper was so great that the city was known as the "American Debrecen," with one of the highest concentrations of Hungarians in the world. History In 1583, a Hungarian poet Stephanus Parmenius joined Humphrey Gilbert's expedition to North America with the intention of writing a chronicle of the voyage and its discoveries. Parmenius reached Newfoundland, likely becoming the first Hungarian in the New World. Hungarians have long settled in the New World, such as Michael de Kovats, the founder of United States Cavalry, activ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Judaism
Judaism ( he, ''Yahăḏūṯ'') is an Abrahamic, monotheistic, and ethnic religion comprising the collective religious, cultural, and legal tradition and civilization of the Jewish people. It has its roots as an organized religion in the Middle East during the Bronze Age. Modern Judaism evolved from Yahwism, the religion of ancient Israel and Judah, by the late 6th century BCE, and is thus considered to be one of the oldest monotheistic religions. Judaism is considered by religious Jews to be the expression of the covenant that God established with the Israelites, their ancestors. It encompasses a wide body of texts, practices, theological positions, and forms of organization. The Torah, as it is commonly understood by Jews, is part of the larger text known as the ''Tanakh''. The ''Tanakh'' is also known to secular scholars of religion as the Hebrew Bible, and to Christians as the " Old Testament". The Torah's supplemental oral tradition is represented by later texts s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chauvenet Prize
The Chauvenet Prize is the highest award for mathematical expository writing. It consists of a prize of $1,000 and a certificate, and is awarded yearly by the Mathematical Association of America in recognition of an outstanding expository article on a mathematical topic. The prize is named in honor of William Chauvenet and was established through a gift from J. L. Coolidge in 1925. The Chauvenet Prize was the first award established by the Mathematical Association of America. A gift from MAA president Walter B. Ford in 1928 allowed the award to be given every 3 years instead of the originally planned 5 years. Winners *1925 G. A. Bliss *1929 T. H. Hildebrandt *1932 G. H. Hardy *1935 Dunham Jackson *1938 G. T. Whyburn *1941 Saunders Mac Lane *1944 R. H. Cameron *1947 Paul Halmos *1950 Mark Kac *1953 E. J. McShane *1956 Richard H. Bruck *1960 Cornelius Lanczos *1963 Philip J. Davis *1964 Leon Henkin *1965 Jack K. Hale & Joseph P. LaSalle *1967 Guido Weiss *1968 Mark ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Van Stockum Dust
In general relativity, the van Stockum dust is an exact solution of the Einstein field equations in which the gravitational field is generated by dust rotating about an axis of cylindrical symmetry. Since the density of the dust is ''increasing'' with distance from this axis, the solution is rather artificial, but as one of the simplest known solutions in general relativity, it stands as a pedagogically important example. This solution is named after Willem Jacob van Stockum, who rediscovered it in 1937 independently of a much earlier discovery by Cornelius Lanczos in 1924. It is currently recommended that the solution be referred to as the Lanczos–van Stockum dust. Derivation One way of obtaining this solution is to look for a cylindrically symmetric perfect fluid solution in which the fluid exhibits ''rigid rotation''. That is, we demand that the world lines of the fluid particles form a timelike congruence having nonzero vorticity but vanishing expansion and shear. (In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lanczos Differentiator
__NOTOC__ Cornelius (Cornel) Lanczos ( hu, Lánczos Kornél, ; born as Kornél Lőwy, until 1906: ''Löwy (Lőwy) Kornél''; February 2, 1893 – June 25, 1974) was a Hungarian-American and later Hungarian-Irish mathematician and physicist. According to György Marx he was one of The Martians. Biography He was born in Fehérvár (Alba Regia), Fejér County, Kingdom of Hungary to Károly Lőwy and Adél Hahn. Lanczos' Ph.D. thesis (1921) was on relativity theory. He sent his thesis copy to Albert Einstein, and Einstein wrote back, saying: "I studied your paper as far as my present overload allowed. I believe I may say this much: this does involve competent and original brainwork, on the basis of which a doctorate should be obtainable ... I gladly accept the honorable dedication."Barbara Gellai (2010) ''The Intrinsic Nature of Things: the life and science of Cornelius Lanczos'', American Mathematical Society In 1924 he discovered an exact solution of the Einstein field equatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lanczos Sigma Factor
In mathematics, σ-approximation adjusts a Fourier summation to greatly reduce the Gibbs phenomenon, which would otherwise occur at discontinuities. A σ-approximated summation for a series of period ''T'' can be written as follows: s(\theta) = \frac a_0 + \sum_^ \operatorname \frac \cdot \left _ \cos \left( \frac \theta \right) + b_k \sin \left( \frac \theta \right) \right in terms of the normalized sinc function \operatorname x = \frac. The term \operatorname \frac is the Lanczos σ factor, which is responsible for eliminating most of the Gibbs phenomenon. It does not do so entirely, however, but one can square or even cube the expression to serially attenuate Gibbs phenomenon in the most extreme cases. See also * Lanczos resampling filtering and Lanczos resampling are two applications of a mathematical formula. It can be used as a low-pass filter or used to smoothly interpolate the value of a digital signal between its samples. In the latter case it maps each sample ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
