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Many Paris Street signs are named for Mathematicians *The n-Category Cafe |
It is my task to convince you not to turn away because you don't understand it. You see my physics students don't understand it... That is because I don't understand it. Nobody does.
~Richard Feynman
The 72nd day of the year; 72 is a pronic, heteromecic, or oblong number (and sometimes pronic is spelled promic). They are numbers that are the product of two consecutive integers
Oblong numbers have the property that if they are used in infinite nested radicals, they produce an integer, √(72+√(72+√(72+...)))=9
72 is the smallest number whose fifth power is the sum of five smaller fifth powers: 195+435+465+475+675=725.
The rule of 72 was once a commonly used approximation in banking and finance for the time it took an investment to double at r%. For a 5% investment, the approximate period would be 72/5 = 14.4 years. The rule applies to compound interest. The rule is based on an approximation of ln(2) = .693..
72 is the smallest number that can be expressed as the difference of the squares of consecutive primes in two distinct ways: {192 - 172} and {112 - 72}
More math facts for every year date here.
EVENTS
1639 Harvard University named after its London born clergyman founder John Harvard. Harvard was founded in 1636 by vote of the Great and General Court of the Massachusetts Bay Colony, making it the oldest institution of higher learning in the United States. Initially called "New College" or "the college at New Towne", the institution was renamed Harvard College on March 13, 1639. It was named after John Harvard, a young English clergyman from Southwark, London, an alumnus of the University of Cambridge (after which Cambridge, Massachusetts is named), who bequeathed the College his library of four hundred books and £779 pounds sterling, which was half of his estate. *Wik
1641 Vincenzo Renieri wrote to Galileo describing certain experiments on falling bodies, including dropping weights from the Tower in Pisa. In his trial a lead weight and a wooden one, of equal sizes, were dropped but in his trial they arrived three cubits apart. He asked Galileo if he had an explanation. At this time Galileo was already old and blind, and his assistant was Viviani. “Thus Vincenzo Viviani’s account of the results of Galileo’s experiments that involved dropping different weights from the top of the bell tower of Pisa seems to be completely unfounded.”
1781 Sir William Herschel discovered Uranus at 10:30 PM.(The first planet discovered by a telescope) During his search for double stars Herschel noticed an object appearing as a nonstellar disk. Herschel originally thought it was a comet or a star. He made many more observations of it, and afterwards Russian Academician Anders Lexell computed the orbit and found it to be probably planetary. Herschel determined in agreement that it must be a planet beyond the orbit of Saturn. He called the new planet the 'Georgian star' (Georgium sidus) after King George III, which also brought him favor; the name didn't stick, however. In France, where reference to the British king was to be avoided if possible, the planet was known as 'Herschel' until the name 'Uranus' was universally adopted.
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*Wik |
Senator William M. Evarts purchased one from a street fakir in order to get rid of him. He took the puzzle home and worked it for hours. The following morning he brought it with him into senate chambers where Senator George Graham Vest stopped by Evarts' desk, borrowed the puzzle and took it to a cloak room. Soon thereafter he was joined by Senators James L. Pugh, James B. Eustis, Edward C. Walthall and John E. Kenna. A page was sent out to buy five of the puzzles and upon his return, the group engaged in a "pig driving contest". About 30 minutes later, Senator Vest announced his accomplishment of driving the last pig in the pen. A few days later a political cartoon in the March 17, 1889 issue of the New York World lampooned President Benjamin Harrison's advisors and cabinet members showing the group sitting around playing the game. The caption read "Will Mr. Harrison be able to get all these hungry pigs in the official pen?"*Antique Toy Collectors of America *Wik
1925 The Butler Act, a law in Tennessee prohibiting the teaching of Darwin’s theory of evolution passed the state senate on March 13, and was signed into law by Governor Austin Peay (for whom the university in Clarksville, Tennessee is named) on March 21. The Butler Act was a 1925 Tennessee law:
That it shall be unlawful for any teacher in any of the Universities, Normals and all other public schools of the State which are supported in whole or in part by the public school funds of the State, to teach any theory that denies the Story of the Divine Creation of man as taught in the Bible, and to teach instead that man has descended from a lower order of animals.It would remain the law in Tennessee until repealed on September 1, 1967. *Wik
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John T Scopes |
1926 Erwin Schrodinger's "Quantisierung als Eigenwertproblem ," the first of six remarkable papers laying out his wave formulation of quantum mechanics, was published in Annalen der Physik *Robert McNess@mcnees
The name Pluto was proposed by Venetia Burney (1918–2009), an eleven-year-old schoolgirl in Oxford, England. Venetia was interested in classical mythology as well as astronomy, and considered the name, a name for the god of the underworld, appropriate for such a presumably dark and cold world. She suggested it in a conversation with her grandfather Falconer Madan, a former librarian at the University of Oxford's Bodleian Library. Madan passed the name to Professor Herbert Hall Turner, who then cabled it to colleagues in the United States.*Wik
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PDP-11 Wik |
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Halley's Comet, March 8, 1986 |
1986 Microsoft Goes Public Ten years after the company's founding, Microsoft Corporation stock goes public at $21 per share. *CHM Allowing for stock splits and reinvestment of dividends, each $21 share then would be worth $9239today (price may be somewhat dated). (I know, you thought computers were just a fad, too.)
1997 Phoenix lights seen at night over Phoenix, Arizona by hundreds of people, and by millions on television. Now a hotly debated controversy.The Phoenix Lights (sometimes called the "Lights Over Phoenix") were a series of widely sighted unidentified flying objects observed in the skies over the southwestern states of Arizona and Nevada on March 13, 1997.
1733 Joseph Priestley (13 Mar 1733, 6 Feb 1804) English chemist, clergyman and political theorist who discovered the element oxygen. His early scientific interest was electricity, but he is remembered for his later work in chemistry, especially gases. He investigated the "fixed air" (carbon dioxide) found in a layer above the liquid in beer brewery fermentation vats. Although known by different names at the time, he also discovered sulphur dioxide, ammonia, nitrogen oxides, carbon monoxide and silicon fluoride. Priestley is remembered for his invention of a way of making soda-water (1772), the pneumatic trough, and recognizing that green plants in light released oxygen. His political opinions and support of the French Revolution, were unpopular. After his home and laboratory were set afire (1791), he sailed for America, arriving at New York on 4 Jun 1794 *TIS
The book below gives a wonderful history of scientific cooperation in this period. "This 18th century group of science fans and practitioners centred around Charles Darwin’s maternal and paternal grandfathers, Josiah Wedgwood and Erasmus Darwin, met monthly at full moon to facilitate the members journey home in the dark. Apart from Priestley, Darwin and Wedgwood notable other members, some corresponding, were Boulton and Watt of steam engine fame, Benjamin Franklin, James Hutton, Joseph Banks, William Herschel and a host of other scientific worthies." *Thony Christie, The lunatic who invented fizzy pop.
1842 Joseph Valentin Boussinesq (13 March 1842 – 19 February 1929) was a French mathematician and physicist who made significant contributions to the theory of hydrodynamics, vibration, light, and heat.
In 1897 he published Théorie de l' écoulement tourbillonnant et tumultueux des liquides, a work that greatly contributed to the study of turbulence and hydrodynamics.
1855 Percival Lowell (13 Mar 1855, 12 Nov 1916) American astronomer who predicted the existence of the planet Pluto and initiated the search that ended in its discovery. Lowell was also passionately committed to finding proof of intelligent life on Mars. In 1894, he founded the Lowell Observatory, atop Mars Hill, at Flagstaff as Arizona's first astronomical observatory. Studying Mars, Lowell drew in intricate detail, the network of several hundred fine, straight lines and their intersection in a number of "oases." Lowell concluded that the bright areas were deserts and the dark ones were patches of vegetation. He believed further, that water from the melting polar cap flowed down the canals toward the equatorial region to revive the vegetation. *TIS
1866 Dayton Clarence Miller (13 Mar 1866, 22 Feb 1941 at age 74)American physicist. Author of The Science of Musical Sounds (1916). Miller's collection of nearly 1,650 flutes and other instruments, and other materials mostly related to the flute, is now at the Library of Congress. To provide a mechanical means of recording sound waves photographically, he invented the phonodeik (1908).( The Phonodeik converts sound waves into visual images. The name, from "to show sound" was suggested by Edward W. Morley. Before electronic oscilloscopes, this device was used for analyzing sounds waves. The Phonodeik can be modified to project sound waves on a screen for public demonstration.*Wik) He became expert in architectural acoustics. During WW I, he was consulted concerning using his photodeik to help locate enemy guns. Miller spent considerable research effort on repeating the Michelson and Morley experiment, proposed by Maxwell, to detect a stationary aether. He spent some time working with Morley (1902-4), then more time at Mt. Wilson, recording results favoring the presence of the aether.*TIS
1899 John Hasbrouck Van Vleck (13 Mar 1899, 27 Oct 1980) was an American physicist and mathematician who shared the Nobel Prize for Physics in 1977 with Philip W. Anderson and Sir Nevill F. Mott. The prize honoured Van Vleck's contributions to the understanding of the behaviour of electrons in magnetic, noncrystalline solid materials. In about 1930, he introduced the contribution of the second-order Zeeman effect into the theory of the paramagnetic susceptibility for the ions of the elements samarium and europium, thus bringing calculations into agreement with experimental results. Hans Bethe's theoretical work (c.1929), was extended by Van Vleck to develop the ligand, or crystal, field theory of molecular bonding. He also studied the theory for the nature of the chemical bond, especially as related to its magnetic properties, and contributed to theory of the spectra of free molecules.*TIS
1925 John Torrence Tate Jr. (March 13, 1925, Oct 16, 2019 ) is an American mathematician, distinguished for many fundamental contributions in algebraic number theory, arithmetic geometry and related areas in algebraic geometry. Tate has been described as "one of the seminal mathematicians for the past half-century" by William Beckner, Chairman of the Department of Mathematics at the University of Texas.*Wik
1928 Paulo Ribenboim (March 13, 1928, )is a mathematician who specializes in number theory. Ribenboim was born in Recife, Brazil, and has lived in Canada since 1962.He has authored 13 books and 120 articles. Ribenboim has been a professor of mathematics at Queen's University in Kingston, Ontario, and is now a professor emeritus.*Wik
DEATHS
1884 Siegfried Heinrich Aronhold (16 July 1819 Angerburg, East Prussia – 13 March 1884, Berlin, Germany) was a German mathematician who worked on invariant theory and introduced the symbolic method.*Wik
1933 Robert Thorburn Ayton Innes (10 Nov 1861; 13 Mar 1933) was a Scottish astronomer who discovered Proxima Centauri (1915), the closest star to earth after the Sun. Invited by David Gill to the Cape Observatory, South Africa (1894), he became a successful binary star observer with the 7-inch refractor (1628 discoveries). His most famous discovery, Proxima Centauri is a faint star near the binary star Alpha Centauri, which is so far south it is
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photo by Lowell Observatory |
1965 Corrado Gini (23 May 1884 – 13 March 1965) was an Italian statistician, demographer and sociologist who developed the Gini coefficient, a measure of the income inequality in a society. Gini was a proponent of organicism and applied it to nations. Gini was a eugenicist, and prior to and during World War II, he was an advocate of Italian Fascism. Following the war, he founded the Italian Unionist Movement, which advocated for the annexation of Italy by the United States.
1923 Peter K Henrici (13 Sept 1923 , 13 March 1987) He made "major contributions to preserving and enriching our mathematical heritage. His books and papers have helped greatly in maintaining numerical analysis as a subject with beauty, order, and structure, in the spirit of the great pioneers of the past. He keeps reminding us to ask what Gauss would have done with a parallel computer - or with a pocket calculator."
"Henrici was truly an internationally recognized numerical analyst, having written 11 books and over 80 research papers. A very cultured person who was also a gifted pianist, he was an outstanding teacher particularly interested in helping younger mathematicians. His lectures showed great polish and inspired many. His guidance and unselfish contributions as an editor have helped make Numerische Mathematik the respected journal it is. For this alone, we owe him a great debt of gratitude." *SAU
Credits :
*CHM=Computer History Museum
*FFF=Kane, Famous First Facts
*NSEC= NASA Solar Eclipse Calendar
*RMAT= The Renaissance Mathematicus, Thony Christie
*SAU=St Andrews Univ. Math History
*TIA = Today in Astronomy
*TIS= Today in Science History
*VFR = V Frederick Rickey, USMA
*Wik = Wikipedia
*WM = Women of Mathematics, Grinstein & Campbell