Friday 31 August 2018

On This Day in Math - August 31



The pursuit of the good and evil are now linked in astronomy as in almost all science. ... The fate of human civilization will depend on whether the rockets of the future carry the astronomer's telescope or a hydrogen bomb.
~Sir Bernard Lovell


The 243rd day of the year; 243 is the largest three digit number that can be expressed as a fifth power (35).

243 is also the sum of five consecutive prime numbers (41 + 43 + 47 + 53 + 59).

Venus' day is 243 Earth days. *Derek Orr

243 is a Harshad number, divisible by the sum of it's digits, and every permutation of its digits is also.


EVENTS

1682 Michael Rolle published an elegant solution to a difficult problem publicly posed by Ozanam: Find four integers the difference of any two of which is a perfect square as well as the sum of the first three will be a perfect square. This brought him public recognition. *VFR Ozanam believed that the smallest of the four numbers that would satisfy these properties would have at least 50 digits. Rolle found four numbers, all satisfying the conditions Ozanam posed, containing only seven digits in each of the four numbers. *Michel Rolle and His Method of Cascades, Christopher Washington

1831, New London Bridge opened to traffic in London. In 1821, a committee was formed by Parliament to consider the poor condition of the existing centuries-old bridge. The arches had been badly damaged by the Great Freeze, so it was decided to build a new bridge. Building commenced under John Rennie in 1825, and completed in 1831, at the expense of the city. The bridge is composed of five arches, and built of Dartmoor granite. It was opened with great splendour by King William the fourth, accompanied by Queen Adelaide, and many of the members of the royal family, August 1st, 1831. In the 1960's it was auctioned and sold for $2,460,000 to Robert McCulloch who moved it to Havasu City, Arizona. The rebuilt London Bridge was completed and dedicated on 10 Oct 1971. *TIS

In 1842, the U.S. Naval Observatory was authorized by an act of Congress, one of the oldest scientific agencies in the U.S. James Melville Gilliss (1811-1865) is considered its founder, who in 1842 he secured the Congressional appropriation for the Depot of Charts and Instruments (est. 1830) to become the Naval Observatory. Its primary task was to care for the Navy's charts, navigational instruments and chronometers, which were calibrated by timing the transit of stars across the meridian. Initially located at Foggy Bottom, the observatory moved in 1893 to its present facility in Washington, DC. Gillis visited Europe to procure instruments, and the books that formed the core of the Naval Observatory Library. Matthew Fontaine Maury was the first director, followed by Gillis (1861-65)*TIS

1846 Le Verrier's announces his prediction of the location of the yet to be discovered planet Neptune. Using only mathematics and astronomical observations of the known planet Uranus and encouraged by physicist Arago, Director of the Paris Observatory, Le Verrier was intensely engaged for months in complex calculations to explain small but systematic discrepancies between Uranus's observed orbit and the one predicted from the laws of gravity of Newton. At the same time, but unknown to Le Verrier, similar calculations were made by John Couch Adams in England. Le Verrier announced his final predicted position for Uranus's unseen perturbing planet publicly to the French Academy on 31 August 1846, two days before Adams's final solution, which turned out to be 12° off the mark, was privately mailed to the Royal Greenwich Observatory. Le Verrier transmitted his own prediction by 18 September letter to Johann Galle of the Berlin Observatory. The letter arrived five days later, and the planet was found with the Berlin Fraunhofer refractor that same evening, 23 September 1846, by Galle and Heinrich d'Arrest within 1° of the predicted location near the boundary between Capricorn and Aquarius. *Wik

1869 Mary Ward was an Anglo Irish amateur scientist who was killed when she fell under the wheels of an experimental steam car built by her cousins. As the event occurred in 1869, she is the world's first known fatal motor vehicle accident victim." *Wik

In 1886, the first U.S. earthquake on record with significant human consequence - the loss of some 100 lives - hit Charleston, S.C. and its massive effect spread through many eastern States. The epicenter was 15 miles northwest of Charleston, where 41 people died, 90 percent of the city's 6,956 brick buildings were damaged, and nearly all of its 14,000 chimneys were broken off at the roof. However, geologically the most severe earthquakes in U.S. history had occurred earlier in the century near the present town of New Madrid, Missouri (16 Dec 1811). The epicenter then was in a sparsely populated region and caused no known casualties, so the human consequences were relatively not significant, although the violent movement of the ground changed the course of the Mississippi River and created many new lakes.*TIS

1899 Cantor, in a letter to Dedekind, remarked that his “diagonal process” can be used to show that the power set of a set has more elements than the set itself. *VFR

1946The New Yorker Magazine devoted its cover, and the entire issue to a ground breaking article by war correspondent John Hersey, Describing the actual after-effects of the Hiroshima bomb, exposing the suffering, and long-lasting effects of the bomb. The US military, US government, and General Groves had pushed the white-wash that there were no significant after-effects, and one spokesman described the bomb as a "nice way to die."
1950 G¨odel addressed the International Congress of Mathematicians, in Cambridge, Massachusetts, on his work in relativity theory. *VFR

1994 David Charles Hahn, later called the "Radioactive Boy Scout" or the "Nuclear Boy Scout", attracted the attention of local police when he was stopped on another matter and they found material in his vehicle that troubled them and he warned that it was radioactive. The gift of a Chemistry set at age twelve sparked his interest, first to make nitroglycerin and then, at age seventeen, to build a homemade breeder nuclear reactor. A Scout in the Boy Scouts of America, Hahn conducted his experiments in secret in a backyard shed at his mother's house in Commerce Township, Michigan. His mother's property was cleaned up by the Environmental Protection Agency ten months later as a Superfund cleanup site. Hahn attained Eagle Scout rank shortly after his lab was dismantled. *R. R. Johnson, Romancing the Atom

2012 A Blue Moon, or the second of two full moons in a single month. August 2012 will have a blue moon on August 31 The last month with two full moons was March of 2010 March 1 and March 30. The next month with a blue moon will be in January of 2018. Once in a Blue moon really isn’t all that often.
Their are alternate definitions for blue moon,f or instance the fourth moon in a quarter.  For that you have to wait until June of 2019.

2012 "Japanese mathematician Shinichi Mochizuki posted four papers on the Internet.
The titles were inscrutable. The volume was daunting: 512 pages in total. The claim was audacious: he said he had proved the ABC Conjecture, a famed, beguilingly simple number theory problem that had stumped mathematicians for decades." From The Paradox of the Proof
by Caroline Chen
.



BIRTHS

1663 Guillaume Amontons (31 Aug 1663; 11 Oct 1705)French physicist, who developed the air thermometer - which relies on increase in volume of a gas (rather than a liquid) with temperature - and used it (1702) to measure change in temperature in terms of a proportional change in pressure. This observation led to the concept of absolute zero in the19th century. Deaf since childhood, Amontons worked on inventions for the deaf, such as the first telegraph, which relied on a telescope, light, and several stations to transmit information over large distances. Amontons' laws of friction, relied upon by engineers for 300 years, state that the frictional force on a body sliding over a surface is proportional to the load that presses them together and is also independent of the areas of the surfaces. *TIS

1821 Hermann Ludwig Ferdinand von Helmholtz (31 Aug 1821; 8 Sep 1894) was a German scientist who contributed much to physiology, optics, electrodynamics, mathematics, and meteorology, including the law of the conservation of energy (1847). He also developed thermodynamics, in particular introducing concept of free energy. In 1850, he measured the speed of a nerve impulse and, in 1851, invented the ophthalmoscope. He discovered the function of the cochlea in the inner ear and developed Thomas Young's theory of color vision (published 1856). His study of muscle action led him to formulate a much more accurate theory concerning the conservation of energy than earlier proposed by Julius Mayer and James Joule. *TIS

1864 Robert Hardie (31 Aug 1864 in George Street, Edinburgh, Scotland - 9 March 1942 in Edinburgh, Scotland) graduated from Oxford and occupied various posts in the Philosophy department of Edinburgh University. He was a founder member of the EMS. *SAU

1880 Heinrich Franz Friedrich Tietze (August 31, 1880 – February 17, 1964) contributed to the foundations of general topology and developed important work on subdivisions of cell complexes. The bulk of this work was carried out after he took up the chair at Munich in 1925.*SAU He is remimbered for the Tietze extension theorem. He also developed the Tietze transformations for group presentations, and was the first to pose the group isomorphism problem.
He was born in Schleinz, Austria and died in Munich, Germany. *Wik

1884 Birthdate of George Alfred L´eon Sarton, (August 31, 1884; Ghent, Belgium - March 22, 1956, Cambridge, Massachusetts) ,historian of science and founder of the journal Isis. *VFR Sarton intended to complete an exhaustive nine volume history of science — which, during the preparation of the second volume, induced him to learn Arabic and travel around the Middle East inspecting original manuscripts of Islamic scientists — but at the time of his death only the first three volumes had been completed. (I. From Homer to Omar Khayyam. — II. From Rabbi Ben Ezra to Roger Bacon, pt. 1-2. — III. Science and learning in the fourteenth -century, pt. 1-2. 1927-48.) The project was inspired by his study of Leonardo da Vinci but the period of Leonardo's life was not reached before the death of Sarton. *Wik


1885 Herbert Westren Turnbull (31 Aug 1885; 4 May 1961)English mathematician who made extensive and notable contributions to the study of algebraic invariants and concomitants of quadratics. Turnbull was also interested in the history of mathematics, writing The Mathematical Discoveries of Newton (1945), and began work on the Correspondence of Isaac Newton.*TIS

1913 Sir Alfred Charles Bernard Lovell (31 Aug 1913, ) is an English radio astronomer who established and directed (1951-81) Jodrell Bank Experimental Station, Cheshire, England, with (then) the world's largest steerable radiotelescope, now named after him Prior to WW II, he worked at Manchester University on cosmic ray research. During the war, he helped develop aircraft onboard radar systems. After the war, to escape interference to radar equipment from city trams, he moved his research to the University's more remote Jodrell Bank property. In 1946, he showed that radar echoes could detect optically invisible daytime meteor showers. He gained funding to build the 250-ft-diam. telescope. When completed in 1957, it was able to track the first artificial satellite, Sputnik I. *TIS

1916 Robert Hanbury Brown (31 Aug 1916; 16 Jan 2002) British astronomer who was a pioneer in radar and observational astronomy. During and after WW II he worked with R.A. Watson-Watt and then E.G. Bowen to develop radar for uses in aerial combat. In the 1950s he applied this experience to radio astronomy, developing radio-telescope technology at Jodrell Bank Observatory and mapping stellar radio sources. He designed a radio interferometer capable of resolving radio stars while eliminating atmospheric distortion from the image (1952). With R.Q. Twiss, Brown applied this method to measuring the angular size of bright visible stars, thus developing the technique of intensity interferometry. They set up an intensity interferometer at Narrabri in New South Wales, Australia, for measurements of hot stars.*TIS





DEATHS

1721 John Keill (1 Dec 1671, 31 Aug 1721) Scottish mathematician and natural philosopher, who was a major proponent of Newton’s theories. He began his university education at Edinburgh under David Gregory, whom he followed to Oxford, where Keill lectured on Newton's work, and eventually became professor of astronomy. In his book, An Examination of Dr. Burnett's Theory of the Earth (1698), Keill applied Newtonian principles challenging Burnett's unsupportable speculations on Earth's formation. In 1701, Keill published Introductio ad Veram Physicam, which was the first series of experimental lectures and provided a clear and influential introduction to Isaac Newton’s Principia. He supported Newton against priority claims by Leibnitz for the invention of calculus.*TIS

1811 Louis-Antoine de Bougainville (12 November 1729 – 31 August 1811) was a French soldier and explorer who wrote a calculus book, but is better known for his other exploits.*SAU A contemporary of James Cook, he took part in the French and Indian War and the unsuccessful French attempt to defend Canada from Britain. He later gained fame for his expeditions to settle the Falkland Islands and his voyages into the Pacific Ocean.*Wik

1918 André-Louis Cholesky (October 15, 1875, August 31, 1918, ) was a French military officer and mathematician. He worked in geodesy and map-making, was involved in surveying in Crete and North Africa before World War I. But he is primarily remembered for the development of a matrix decomposition known as the Cholesky decomposition which he used in his surveying work. He served the French military as engineer officer and was killed in battle a few months before the end of World War I; his discovery was published posthumously by his fellow officer in the "Bulletin Géodésique". *Wik

1945 Stefan Banach died. (30 Mar 1892, 31 Aug 1945) Polish mathematician who founded modern functional analysis and helped develop the theory of topological vector spaces. In addition, he contributed to measure theory, integration, the theory of sets, and orthogonal series. In his dissertation, written in 1920, he defined axiomatically what today is called a Banach space. The idea was introduced by others at about the same time (for example Wiener introduced the notion but did not develop the theory). The name 'Banach space' was coined by Fréchet. Banach algebras were also named after him. The importance of Banach's contribution is that he developed a systematic theory of functional analysis, where before there had only been isolated results which were later seen to fit into the new theory. *TIS

1950 Subbayya Sivasankaranarayana Pillai (April 5, 1901 Nagercoil, Tamil Nadu - 31 August 1950, Cairo, Egypt) was an Nagercoil native Indian mathematician specializing in number theory. His contribution to Waring's problem was described in 1950 by K. S. Chandrasekharan as "almost certainly his best piece of work and one of the very best achievements in Indian Mathematics since Ramanujan". In number theory, a Pillai prime, named for him, is a prime number p for which there is an integer n > 0 such that the factorial of n is one less than a multiple of the prime, but the prime is not one more than a multiple of n. To put it algebraically, \(n! \equiv -1 \mod p\) but \(p \not\equiv 1 \mod n \). The first few Pillai primes are 23, 29, 59, 61, 67, 71, 79, 83, 109, 137, 139, 149, 193, ... (sequence A063980 in OEIS). *Wik

2005 Sir Joseph Rotblat (4 Nov 1908, 31 Aug 2005)Polish-born British physicist who is a leading critic of nuclear weaponry. Rotblat and the Pugwash Conferences, "for their efforts to diminish the part played by nuclear arms in international politics and in the longer run to eliminate such arms," received the Nobel Peace Prize in 1995. Forty years earlier, he and other scientists, with philosopher Bertrand Russell and Albert Einstein, published a manifesto calling on researchers to take responsibility for their work, particularly those working on the atomic bomb. This led to the Pugwash Conferences on Science and World Affairs, first convened in 1957 in Pugwash, Nova Scotia, Canada. He was secretary-general (1957-73), and president (from 1988) of this London-based worldwide organization. *TIS


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

Thursday 30 August 2018

On This Day in Math - August 30






Frustra fit per plura, quod fieri potest per pauciora.


It is vain to do with more what can be done with less.

~William of Ockham


The 242nd day of the year; 242 has six divisors...but 243, 244, and 245 also each has six divisors. 242 is the smallest integer to begin a run of four consecutive integers all of which have the same number of divisors. (What is the smallest integer that begins a run of three consecutive integers with an equal number of divisors?)

242 is not only a palindrome in base ten, it is also a palindrome in base 3, \( 22222_3\) and base 7, \( 464_7 \). (What palindrome in base ten is also a palindrome in the most other bases 2-9?)


EVENTS

In 1831, Charles Darwin replied to the letter from Revd. Henslow telling him of the offer to sail on the H.M.S. Beagle. Darwin's had learned natural history from Henslow, who had recommended him for the unpaid position as a naturalist. Darwin told Henslow that his father would not permit him to leave on such a voyage. Meanwhile, his father had written to his brother-in-law, Josiah Wedgwood II, about his concerns regarding the proposed two-year jaunt. This afternoon Darwin prepared to join the Wedgwoods for the next day's beginning of the shooting season by riding to Maer Hall, the Wedgwood home. The Darwin family was related to the Wedgwood family through the marriage of Darwin's father to the daughter of the first Josiah Wedgwood, the famous potter. *TIS

1791 Thomas Jefferson sends a letter to Benjamin Banneker after receiving his almanac and a letter announcing that, "Sir, I freely and cheerfully acknowledge, that I am of the African race, and in that color which is natural to them of the deepest dye". Jefferson responds that, " I thank you sincerely for your letter of the 19th. instant and for the Almanac it contained. no body wishes more than I do to see such proofs as you exhibit, that nature has given to our black brethren, talents equal to those of the other colours of men, that the appearance of a want of them is owing merely to the degraded condition of their existence both in Africa and America. I can add with truth that no body wishes more ardently to see a good system commenced for raising the condition both of their body & mind to what it ought to be, as fast as the imbecillity of their present existence, and other circumstance which cannot be neglected, will admit. I have taken the liberty of sending your almanac to Monsieur de Condorcet, Secretary of the Academy of sciences at Paris, and member of the Philanthropic society because I considered it as a document to which your whole colour had a right for their justification against the doubts which have been entertained of them. I am with great esteem, Sir, Your most obedt. humble servt. Th. Jefferson" *Mathematicians of the African Diaspora, SUNY at Buffalo

In 1831, Michael Faraday demonstrated the first electrical transformer.*TIS
 


1908 A committee appointed by the Swiss society of naturalists reported its willingness, provided sufficient financial assistance could be secured, to publish the complete works of Euler in about 40 volumes. Today 80 volumes of Euler’s Opera Omnia have been published, and the end is hardly in sight.*VFR

In 1963, the "Hot Line" communications link between the White House, Washington D.C. and the Kremlin, Moscow, went into operation to provide a direct two-way communications channel between the American and Soviet governments in the event of an international crisis. This was one year after the Cuban Missile Crisis. It consisted of one full-time duplex wire telegraph circuit, routed Washington- London- Copenhagen- Stockholm- Helsinki- Moscow, used for the transmission of messages and one full-time duplex radiotelegraph circuit, routed Washington- Tangier- Moscow used for service communications and for coordination of operations between the two terminal points. Note, this was not a telephone voice link.*TIS

In 1979, Comet Howard-Koomen-Michels (SOLWIND I) collided with the Sun, the first recorded comet to collide with Sun and the first discovered by a spacecraft. The coronographs taken on 30 and 31 Aug 1979 from the satellite P78-1 used to monitor solar corona activity were not inspected until Sep 1981, by Russ Howard. The recording instruments were designed and operated by Martin Koomen and Don Michels. The remarkable series of images showed the comet heading around the Sun. Its perihelion distance was too small, and the head did not reappear from behind the Sun, presumably disintegrated by the heat of the sun. The decapitated comet's tail continued, becoming fan-like, brightening the corona, until dissipated and blown away from the Sun*TIS



BIRTHS

1804 Ernst Wilhelm Grebe (30 August, 1804 - 14 January, 1874) is remembered only for a thoughtful paper that appeared in 1847 concerning some interesting properties of the triangle: If on each side of a given (arbitrary) triangle ABC one describes a square ( exterior to ABC ), then the extended outside sides of the squares, thus obtained, form a similar triangle A'B'C'. The center of similarity of both triangles is the meeting point of the straight lines AA', BB', CC'. In German this point was first called _Grebe'schen Punkt_ [Grebe's point], a TERM which seems to have been first referred to by E. Hain as early as 1875, in his paper "Ueber den Grebe'schen Punkt" [ _Archiv der Mathematik und Physik_ (= Grunert's _Archive_) volume LVIII (1876), pp. 84-89 ] *Julio Gonzalez Cabillon , Posting to the Historia Matematica discussion group
He also named the Vecten point.

1819 Joseph Alfred Serret (30 Aug 1819 in Paris, France - 2 March 1885 in Versailles, France) He was a French mathematician best remembered for the Serret-Frenet formulas for a space-curve. In 1860 Serret succeeded Poinsot in the Académie des Sciences. In 1871 he retired to Versailles as his health began to deteriorate.
Serret also worked in number theory, calculus and mechanics. He edited the works of Lagrange which were published in 14 volumes between 1867 and 1892. He also edited the 5th edition of Monge in 1850.*SAU

1856 Carl David Tolmé Runge worked on a procedure for the numerical solution of algebraic equations and later studied the wavelengths of the spectral lines of elements. *SAU In numerical analysis, the Runge–Kutta methods that are named for him are an important family of implicit and explicit iterative methods for the approximation of solutions of ordinary differential equations. These techniques were developed around 1900  Runge and M.W. Kutta.*Wik When  your regular walking partners include Felix Klein, David Hilbert, and Hermann Minkowski, you can't count on easily impressing them with your mental math skills, but it seems that Runge did so frequently.  Once on their regular walks Klein brought up some departmental event that required them to know what date Easter would occur the next year.  The group immediately turned to the idea of where they might acquire a calendar for the following year along the walk; all that is, except Runge who fell silent for a few yards, and then announced the date.

1871 Sir Ernest Rutherford (30 Aug 1871; 19 Oct 1937). (baron) New Zealand-born British physicist who laid the groundwork for the development of nuclear physics. He worked under Sir J. J. Thomson at Cambridge University (1895-98). Then he collaborated with Frederick Soddy in studying radioactivity. In 1899 he discovered alpha particles and beta particles, followed by the discovery of gamma radiation the following year. In 1905, with Soddy, he announced that radioactive decay involves a series of transformations. In 1907, with Hans Geiger and Ernest Marsden, he devised the alpha-particle scattering experiment that led in 1911 to the discovery of the atomic nucleus. In 1919 he achieved the artificial splitting of light atoms. In 1908 he was awarded the Nobel Prize for Chemistry. *TIS A story is told by A.. V. Hill that Rutherford had told him once, "I've just been reading some of my early papers, and when I had read them for a bit I said to myself, "Ernest my boy, you used to be a darn clever fellow.'" *Walter Gratzer, Eurekas and Euphorias, pg 27
 [I love this quote from a few years before his death. "The energy produced by the breaking down of the atom is a very poor kind of thing. Anyone who expects a source of power from the transformation of these atoms is talking moonshine."]

1906 Olga Taussky-Todd She received her Ph.D. in 1930 under Philip Furtwangler at Vienna in number theory. Her first job involved editing Hilbert’s papers on number theory.*VFR

1907 John Mauchly (30 Aug 1907; 8 Jan 1980) American physicist and engineer, who with John P. Eckert invented (1946) the Electronic Numerical Integrator and Computer (ENIAC), the first general-purpose electronic computer. Mauchly initially conceived of the computer's architecture, and Eckert possessed the engineering skills to bring the idea to life. ENIAC was developed (1946) for the US Army Ordnance Department as what was probably the first general-purpose electronic computer. It was a vast machine, consuming 100 kW of electric power and containing 18,000 electronic valves. Their successful UNIVAC computer (1951) was the first commercial computer, and introduced magnetic tape for programming.*TIS



1907 Gordon Brown founded the Servomechanisms Laboratory at MIT, which pioneered the development of feedback-control theory, computer technology, and automatic control of machine tools and had many famous graduate students who went on to become major contributors in the fields of Electrical Engineering and Computer Science. *CHM

1912 E.M. Purcell (30 Aug 1912; 7 Mar 1997) American physicist who shared, with Felix Bloch of the United States, the Nobel Prize for Physics in 1952 for his independent discovery (1946) of nuclear magnetic resonance in liquids and in solids. Nuclear magnetic resonance (NMR) has become widely used to study the molecular structure of pure materials and the composition of mixtures. The method detects and measures the magnetic fields of atomic nuclei. *TIS




DEATHS

1621 Baha' ad-Din al-Amili (27 Feb 1547 in Baalbek, now in Lebanon - 30 Aug 1621 in Isfahan, Iran) was a Lebanese-born mathematician who wrote influential works on arithmetic, astronomy and grammar. Perhaps his most famous mathematical work was Quintessence of Calculation which was a treatise in ten sections, strongly influenced by The Key to Arithmetic (1427) by Jamshid al-Kashi. *SAU



1844 Francis Baily   (28 Apr 1774, 30 Aug 1844)English astronomer who detected the phenomenon called "Baily's beads" during an annular eclipse of the Sun on 15 May 1836. His vivid description aroused new interest in the study of eclipses. After retiring in 1825 from a successful business career, Baily turned to science. Baily revised several star catalogs, repeated Henry Cavendish's experiments to determine the density of the Earth, and measured its elliptical shape. His protests regarding the British Nautical Almanac, then notorious for its errors, were instrumental in bringing about its reform.*TIS  A really nice discussion of the many contributions of Baily is in this post at The Renaissance Mathematicus, To whet your appetite, " Baily’s Flamsteed memoir had a major influence on the history and the  historiography of science; he had succeeded in pricking Newton’s  hagiographic bubble. St Isaac had been taken down a peg or two. Baily’s  work marks a turning point in our understanding of Newton moving him  along the road from plastic saint to real, if somewhat unpleasant, human  being. Sometimes editing star catalogues can lead to unexpected results  for the history of science."

1901 Biquard Pierre, (30 August 1901 in Paris - 28 April 1992 in Paris)In 1932, He discovered light diffraction by ultrasonic waves: Pierre Biquard, born 30 Aug 1901, friend of Frédéric Joliot Curie *Arjen Dijksman ‏@materion

1928 Wilhelm Wien  (13 Jan 1864, 30 Aug 1928)German physicist who received the Nobel Prize for Physics in 1911 for his displacement law concerning the radiation emitted by the perfectly efficient blackbody (a surface that absorbs all radiant energy falling on it). While studying streams of ionized gas Wien, in 1898, identified a positive particle equal in mass to the hydrogen atom. Wien, with this work, laid the foundation of mass spectroscopy. J J Thomson refined Wien's apparatus and conducted further experiments in 1913 then, after work by E Rutherford in 1919, Wien's particle was accepted and named the proton. Wien also made important contributions to the study of cathode rays, X-rays and canal rays.*TIS [I find it curiously interesting that all three of  the  great physicists mentioned here either were born or died this day]

1940 Sir J(oseph) J(ohn) Thomson (born 18 Dec 1856, 30 Aug 1940 )was an English physicist who helped revolutionize the knowledge of atomic structure by his discovery of the electron (1897). He received the Nobel Prize for Physics in 1906 and was knighted in 1908. Thomson experimented with currents of  electricity inside empty glass tubes, investigating a long-standing puzzle known as "cathode rays." His experiments prompted him to make a bold proposal: these mysterious rays are streams of particles much smaller than atoms. He called these particles "corpuscles," and suggested that they might make up all of the matter in atoms. It was startling to imagine a particles inside the atom at a time when most people thought that the atom was indivisible, the most fundamental unit of matter.*TIS

1995 Fischer Sheffey Black (January 11, 1938, August 30, 1995) was an American economist, best known as one of the authors of the famous Black–Scholes equation.In 1973, Black, along with Myron Scholes, published the paper 'The Pricing of Options and Corporate Liabilities' in 'The Journal of Political Economy'. This was his most famous work and included the Black–Scholes equation. The Nobel Prize is not given posthumously, so it was not awarded to Black in 1997 when his co-author Myron Scholes received the honor for their landmark work on option pricing along with Robert C. Merton, another pioneer in the development of valuation of stock options. In the announcement of the award that year, the Nobel committee prominently mentioned Black's key role.*Wik

2004 Fred Lawrence Whipple  (5 Nov 1906, 30 Aug 2004) was an American astronomer who proposed the "dirty snowball" model for comet nuclei. In the 1930s, using a new, two-station method of photography, he determined meteor trajectories and found that nearly all visible meteors are made up of fragile material from comets, and that none come from beyond the solar system. Whipple suggested (1950) that comets have icy cores inside thin insulating layers of dirt, and that jets of material ejected as a result of solar heating were the cause of orbital changes. This model was confirmed in 1986 when spacecraft flew past comet Halley. Whipple’s work on tracking artificial satellites led to improved knowledge of the shape of the earth and greatly improved positions on earth. *TIS


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


Wednesday 29 August 2018

On This Day in Math - August 29


Jeannie at VLA


In most sciences one generation tears down what another has built,
and what one has established, another undoes.
In mathematics alone each generation adds a new storey to the old structure.
~Hermann Hankel

The 241st day of the year; 241 is the larger of a pair of twin primes. The larger of a pair of twin primes is always one more than a multiple of six; the smaller is always one less than a multiple of six.

2+4+1 is prime. 241 is the 53rd prime. (53 is also prime) *Derek Orr

241 is also The smallest prime p such that p plus the reversal of p equals a palindromic prime.  241 + 142 = 383; which is a prime palindrome.

And it is the largest known prime p such that the reversal of (p! + p) is prime.  (241! + 241 ends with a string of fifty-five zeros, and then 241 :
980360372638941007038951797078339359751464353463061342202811
188548638347461066010066193275864531994024640834549254693776
854464608509281547718518965382728677985343589672835884994580
815417004715718468026937051493675623385569404900262441027874
255428340399091926993707625233667755768320823071062785275404
107485450075779940944580451919726756974354635829128751944137
27644867102380111026020691554782580923999494640500736
0000000000000000000000000000000000000000000000000000000241
and if you write the reversal of that, it's prime.



EVENTS

1609 Galileo writes to his brother in Florence to tell him about his telescope presentation to the Doge on the 24th of August.

1654 Fermat to Pascal Saturday, August 29, 1654
Monsieur,
Our interchange of blows still continues, and I am well pleased that our thoughts are in such complete adjustment as it seems since they have taken the same direction and followed the same road. Your recent Trait´e du triangle arithmetique and its applications are an authentic proof and if my computations do me no wrong, your eleventh consequence went by post from Paris to Toulouse while my theorem, on figurate numbers, which is virtually the same, was going from Toulouse to Paris. I have not been on watch for failure while I have been at work on the problem and I am persuaded that the true way to escape failure is by concurring with you. But if I should say more, it would he of the nature of a Compliment and we have banished that enemy of sweet and easy conversation. It is now my turn to give you some of my numerical discoveries, but the end of the parliament augments my duties and I hope that out of your goodness you will allow me due and almost necessary respite.
In the same letter he states that, "Meditate however, if you find it convenient, on this theorem: The squared powers of 2 augmented by unity [I.e. 22n+1] are always prime numbers. [That is,] The square of 2 augmented by unity makes 5 which is a prime number;The square of the square makes 16 which, when unity is added makes 17, a prime number; The square of 16 makes 256 which, when unity is added, makes 257, a prime number; The square of 256 makes 65536 which, when unity is added, makes 65537, a prime number; and so to infinity. This is a property whose truth I will answer to you. The proof of it is very difficult (impossible, since the statement, as Euler would show later, is not true)and I assure you that I have not yet been able to find it fully." * York University Maths Dept

1692 For his services to the field of astronomy, Johann Philipp von Wurzelbauer was ennobled in 1692 by Leopold I, Holy Roman Emperor and added the von to his name. *Wik

1831 Michael Faraday discovered electrical induction. *VFR In 1831, Michael Faraday wound a thick iron ring on one side with insulated wire that was connected to a battery. He then wound the opposite side with wire connected to a galvanometer. He found that upon closing the battery circuit, there was a deflection of the galvanometer in the second circuit. Then he was astonished to see the galvanometer needle jump in the opposite direction when the battery circuit was opened. He had discovered that a current was induced in the secondary when a current in the primary was connected and an induced current in the opposite direction when the primary current was disconnected.*TIS

1740 In a letter to Euler dated August 29th, 1740, Philippe Naudé (the Younger) asked Euler in how many ways a number n can be written as a sum of positive integers. In his answer written on September 12th (23rd), Euler explained that if we denote
this “partition number” by p(n), then
*Correspondence of Leonhard Euler with Christian Goldbach, Springer

1859 Amateur English astronomers Richard Carrington and Richard Hodgson, independently observed a "white light flare" emanating from the surface of the sun. Less than a day later, Earth's magnetic field was knocked awry. Across America and Europe, telegraph wires sparked and failed.
Fewer than 18 hours elapsed between the flare and the geomagnetic storm on Earth. That meant whatever had exploded off the sun must have traveled at more than 5 million miles per hour. *NY Times

1899 Dedekind sends a letter to Georg Cantor that includes a proof of the Schroder-Bernstein Theorem (Let A and B be sets. If there is a 1-1 correspondence from A to B and a 1-1 corespondence from B to A, then the sets have the same cardinality.) *Cantorian Set Theory and Limitation of Size By Michael Hallett

In 1940, Sir Henry Tizard led a mission of leading British and Canadian scientists to the USA to brief official American representatives on devices under active development for war use and to enlist the support of American scientists. Thus began a close cooperation of Anglo-American scientists in such fields as aeronautics and rocketry. His influence probably made the difference between defeat or victory at the Battle of Britain in 1940. *TIS

1949 the USSR tested their first atomic device, "First Lightning." It was an an implosive type plutonium bomb, detonated at the Semipalatinsk test range, giving up to a 20 kiloton yield. In the U.S. it was calledJoe No. 1 ("Joe" was nickname for Y. Stalin.) This event came five years earlier than anyone in the West had predicted, largely due to one man, the spy Klaus Fuchs. As a Los Alamos physicist, Fuchs had passed detailed blue prints of the original American Trinity bomb design to the Russians. With the emergence of the USSR as a nuclear rival, America's monopoly of atomic weaponry was ended giving the U.S. strong motivation for intensifying its program of nuclear testing. Thus the Cold War was launched.*TIS

1970 Oscar Morgenstern writes in his diary that Gödel would NOT publish his ontological proof for the existence of God. The first version of the ontological proof in Gödel's papers is dated "around 1941". Gödel is not known to have told anyone about his work on the proof until 1970, when he thought he was dying. In February, he allowed Dana Scott to copy out a version of the proof, which circulated privately. In August 1970, Gödel told Oskar Morgenstern that he was "satisfied" with the proof, but Morgenstern recorded in his diary entry for 29 August 1970, that Gödel would not publish because he was afraid that others might think "that he actually believes in God, whereas he is only engaged in a logical investigation (that is, in showing that such a proof with classical assumptions (completeness, etc.) correspondingly axiomatized, is possible) *Wik

1990 The British Computer Misuse Act goes into effect One of the earliest laws anywhere designed to address computer fraud, the Act resulted from a long debate in the 1980s over failed prosecutions of hackers -- in one well-publicized case, two men hacked into a British Telecom computer leaving messages in the Duke of Edinburgh's private mailbox. *CHM




BIRTHS

1756 Jan Śniadecki (August 29, 1756– November 9, 1830) was a Polish mathematician, philosopher and astronomer at the turn of the 18th and 19th centuries.
Born in Żnin, Śniadecki studied at Kraków University and in Paris. He was rector of the Imperial University of Vilnius, a member of the Commission of National Education, and director of astronomical observatories at Kraków and Vilnius. He died at Jašiūnai Manor near Vilnius.
Śniadecki published many works, including his observations on recently discovered planetoids. His O rachunku losów (On the Calculation of Chance, 1817) was a pioneering work in probability. *Wik He is considered as the best Polish mathematician born in the 18th century.

1876 Charles F. Kettering (29 Aug 1876; 25 Nov 1958) was an American engineer whose 140 patents included the electric starter, car lighting and ignition systems. In his early career, with the National Cash Register Co., Dayton (1904-09), he created the first electric cash register with an electric motor that opened the drawer. When he co-founded the Dayton Engineering Laboratories Company (DELCO, with Edward A. Deeds) he invented the key-operated self-starting motor for the Cadillac (1912) and it spread to nearly all new cars by the 1920's. As vice president and director of research for General Motors Corp. (1920-47) he developed engines, quick-drying lacquer finishes, anti-knock fuels, and variable-speed transmissions.*TIS

1881 Ferdinand Springer born, The founder of an important publishing house,. Today Springer-Verlag is one of the most important publishers of advanced work on mathematics. *VFR

1904 Leonard Roth (29 August 1904 Edmonton, London, England – 28 November 1968 Pittsburgh, Pennsylvania) British Mathematician who worked primarily in Algebraic Geometry. *SAU



DEATHS

1873 Hermann Hankel (14 February 1839 - 29 August 1873) He studied and worked with, among others, Möbius, Riemann, Weierstrass and Kronecker. His 1867 exposition on complex numbers and quaternions is particularly memorable. For example, Fischbein notes that he solved the problem of products of negative numbers by proving the following theorem: "The only multiplication in R which may be considered as an extension of the usual multiplication in R+ by respecting the law of distributivity to the left and the right is that which conforms to the rule of signs." *Wik

1930 James Bolam (1839 in Newcastle, England - 29 Aug 1930 in St Helen's, Drumchapel, Dumbartonshire, Scotland) was educated at Newcastle. He became head of the Government Navigation School (later the Leith Nautical College). He was a founder member of the EMS and became an honorary member in 1923. *SAU

1937 Otto Ludwig Hölder (December 22, 1859 – August 29, 1937) worked on the convergence of Fourier series and in 1884 he discovered the inequality now named after him. He became interested in group theory through Kronecker and Klein and proved the uniqueness of the factor groups in a composition series. *SAU

1967 Charles Brace Darrow (10 Aug 1889, 29 Aug 1967) was an American inventor who designed the board game Monopoly. He had invented the game on 7 Mar 1933, though it was preceded by other real-estate board games. On 31 Dec 1935, a patent was issued for the game of Monopoly assigned to Parker Brothers, Inc., by Charles Darrow of Pennsylvania (No. 2,026,082). The patent titled it a "Board Game Apparatus" and described it as "intended primarily to provide a game of barter, thus involving trading and bargaining" in which "much of the interest in the game lies in trading and in striking shrewd bargains." Illustrations included with the patent showed not only the playing board and pieces, cards, and the scrip money. *TIS

1975 Éamon de Valera (14 October 1882, 29 August 1975) was one of the dominant political figures in twentieth century Ireland, serving as head of government of the Irish Free State and head of government and head of state of Ireland. He also introduced the Constitution of Ireland.
De Valera was a leader of Ireland's struggle for independence from Britain in the Irish War of Independence and of the anti-Treaty forces in the ensuing Irish Civil War (1922–23). In 1926, he founded Fianna Fáil and was head of government from 1932–48, 1951–54 and 1957–59 and President of Ireland from 1959–73.
In his youth he had trained as a mathematician and taught mathematics prior to the Easter Rising. Throughout his life he maintained an interest in mathematics and returned to it with a passion in his later life. *Wik



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

Tuesday 28 August 2018

On This Day in Math - August 28



As long as algebra and geometry have been separated, their progress have been slow and their uses limited; but when these two sciences have been united, they have lent each mutual forces, and have marched together towards perfection.
~Joseph Louis Lagrange


The 240th day of the year; 240 has more divisors (20 of them) than any previous number. What would be the next number that has more?

240 is the product of the first 6 Fibonacci numbers  240 = 1*1*2*3*5*8    *Derek Orr
These are often called Fibonacci factorials or fibonorials. 240 would be \(6!_F\), also called the Fibonacci factorial

The Kissing Number, the number of spheres that can be placed around a central sphere so that they all are touching it, for the eighth dimension is 240. Beyond the fourth dimension, only the eighth and twenty-fourth are known exactly. The 24th dimension is the highest dimension for which the exact "kissing number", is known. For the 24th dimension, the "kissing number is 196,560.




EVENTS

412 BC The ancient city of Syracuse suffered heavily under siege by the Athenians during the Peloponnesian War. A turn of events occurred during the Second Battle of Syracuse: on Aug. 28, 41.C. a lunar eclipse occurred, causing the superstitious Athenians to delay departure. The Syracuseans took advantage of Athenian indecision and decisively defeated the unprotected Athenian expedition as it sat exposed in the harbor. *listosaur.com

1666 John Evelyn Records in his diary: "to the Royal Society, where one Mercator, an excellent mathematician, produced his rare clock and new motion to perform the equations, and Mr. Rooke, his new pendulum." The Mercator is Nicholas Mercator who taught mathematics in London (1658–1682). He designed a marine chronometer for Charles II, and designed and constructed the fountains at the Palace of Versailles. Mathematically, he is most well known for his treatise Logarithmo-technica on logarithms, published in 1668 in which he described the Mercator series, also independently discovered by Gregory Saint-Vincent \( \ln(1 + x) = x - \frac{1}{2}x^2 + \frac{1}{3}x^3 - \frac{1}{4}x^4 + \cdots. \)
I suspect the "Mr Rooke" should have been Hooke who is mentioned at the meeting in Pepys' Diary. *Wik, *John Evelyn Diary

1730 Murder by Unicorn Horn on a Holborn skittle-ground : On the 28th of August 1730, Joseph Hastings died after receiving “several mortal Bruises with an Unicorn’s Horn”, wielded by John Williams of St. Andrew’s Holborn eleven days earlier. The assault occurred on a Holborn skittle-ground, witnessed by several local men.
Williams was angered by Hastings response to his offer to purchase the (probably Narwhale) horn and an argument ensued which led to the beating. More detail at Sloan Letters

1742 a letter from Euler to Goldbach in 1742, Euler proves no number of the form 4n4 +1 can be a prime. In the letter he showed that 1 + 4x4 =(2x2 + 2x + 1)(2x2 − 2x + 1) *Euler Correspondence

In 1789, Enceladus, the sixth-largest moon of Saturn, was discovered by Fredrick William Herschel on August 28, 1789, during the first use of his new 1.2 m (47 in) telescope, then the largest in the world. Little was known about Enceladus until the two Voyager spacecraft passed near it in the early 1980s.
Enceladus is named after the giant Enceladus of Greek mythology. The name Enceladus—like the names of each of the first seven satellites of Saturn to be discovered—was suggested by William Herschel's son John Herschel in his 1847 publication Results of Astronomical Observations made at the Cape of Good Hope. He chose these names because Saturn, known in Greek mythology as Cronus, was the leader of the Titans. *Wik

1837 Pharmacists John Lea and William Perrins began manufacturing Worcester sauce on this day. Lea and Perrins sauce is still manufactured at the Midlands Road factory in Worcester, where production first began. In 1916 Perrins used some of the profits to found the Dyson Perrins organic chemistry laboratory at Oxford University. *rsc.org

Scientific American@sciam
1845 the first issue of the Scientific American was published by Rufus Porter (1792-1884), a versatile if eccentric Yankee, who was by turns a portrait-painter, schoolmaster, inventor and editor. While the paper was still a small weekly journal with a circulation less than 300, he offered it for sale. It was bought for $800 in July 1846 by 20-year-old Alfred Ely Beach (1826-1896) as editor, and Orson Desaix Munn (1824-1907). Together, they built it over the years into a great and unique periodical. Their circulation reached 10,000 by 1848, 20,000 by 1852, and 30,000 by 1853.*TIS




1893 The first day of the Evanston Colloquial lectures by Felix Klein which would continue until 9 September.
*Karen Hunger Parshall, David E. Rowe; The Emergence of the American Mathematical Research Community, 1876-1900

1961 The Board of Governors of the MAA voted to name Dr. Mina S. Rees, (first) Dean of Graduate Studies at the City University of New York, the first recipient of their Award for Distinguished Service to Mathematics. From 1946 to 1953 she held several important positions at the Office of Naval Research and was instrumental in getting ONR to adopt the policy that mathematics was part of this country’s total scientific effort and should be properly supported by government-sponsored research programs. [AMM 69(1962), pp. 185-187]. *VFR

1974 Sweden issued a stamp picturing a spool and thread, with the thread stretched to form a string figure of a hyperbola. [Scott #1094]. *VFR
HT to Emma L Bell, Storax Sedan, and Glen Carlson for image

1993, a picture was taken showing the first moon of an asteroid. The asteroid 243 Ida and its newly-discovered moon, Dactyl was imaged by NASA's Galileo spacecraft, about 14 minutes before its closest approach (within 2,400-km or 1,500 miles) to the asteroid. Ida is about 52 km (32 mi) in length and is irregularly shaped. It shows numerous craters, including many degraded craters, indicating Ida's surface is older than previously thought. Dactyl is only about 1.4-km in diameter, and it is spectrally different from Ida data. The picture was released on 26 Mar 1994. Galileo had encountered the first asteroid - 951 Gaspra - on 29 Oct 1991. Galileo continued on its mission to study Jupiter, beginning its orbit of the planet on 7 Dec 1995.*TIS

2009 The Australian Govt replies to a letter written "To A Top Scientist" by an Australian schoolboy shortly after the launch of Sputnik fifty-two years earlier with his suggested designs for a rocket ship. See all the details at this page from *Letters of Note


BIRTHS

1796 Irénée-Jules Bienaymé (28 August 1796, 19 October 1878), was a French statistician. He built on the legacy of Laplace generalizing his least squares method. He contributed to the fields and probability, and statistics and to their application to finance, demography and social sciences. In particular, he formulated the Bienaymé-Chebyshev inequality concerning the law of large numbers and the Bienaymé formula for the variance of a sum of uncorrelated random variables.*Wik

1801 Antoine-Augustin Cournot (28 Aug 1801; 31 Mar 1877) French economist and mathematician, who was the first economist who applied mathematics to the treatment of economic questions. In 1838, he published Recherches sur les principes mathématiques de la théorie des richesses (Researches into the Mathematical Principles of the Theory of Wealth) which was a treatment of mathematical economics. In particular, he considered the supply-and-demand functions. Further, he studied the conditions for equilibrium with monopoly, duopoly and perfect competition. He included the effect of taxes, treated as changes in production costs, and discussed problems of international trade. His definition of a market is still the basis for that presently used in economics. In other work, he applied probability to legal statistics *TIS

1863 Andre-Eugene Blondel (28 Aug 1863; 15 Nov 1938) was a French physicist who invented (1893) the electromagnetic oscillograph, a device that allowed electrical researchers to observe the intensity of alternating currents. In 1894, he proposed the lumen and other new photometric units for use in photometry, based on the metre and the Violle candle. Endorsed in 1896 by the International Electrical Congress, his system is still in use with only minor modifications. Blondel was a pioneer in the high voltage long distance transport of electric power, and also contributed to developments in wireless telegraphy, acoustics, and mechanics. He proposed theories for induction motors and coupling of a.c. generators.*TIS (Invention of the Oscillograph is also credited to William Du Bois Duddell.)

1867 Maxime Bˆochner born. After receiving his doctorate under Felix Klein in 1891 he returned to Harvard for a lifetime of teaching and research in differential equations. *VFR

1883 Jan A Schouten worked on tensor analysis and its applications.*SAU

1901 Kurt Otto Friedrichs (September 28, 1901 – December 31, 1982) was a noted German American mathematician. He was the co-founder of the Courant Institute at New York University and recipient of the National Medal of Science.*Wik

1911 Shizuo Kakutani August 28 1911, August 17 2004) was a Japanese-born American mathematician, best known for his eponymous fixed-point theorem.
The Kakutani fixed-point theorem is a generalization of Brouwer's fixed-point theorem, holding for generalized correspondences instead of functions. Its most important uses are in proving the existence of Nash equilibria in game theory, and the Arrow–Debreu–McKenzie model of general equilibrium theory.
Kakutani's other mathematical contributions include the Kakutani skyscraper, a concept in ergodic theory (a branch of mathematics that studies dynamical systems with an invariant measure and related problems). They also include his solution of the Poisson equation using the methods of stochastic analysis.
The Collatz (or 3n+1) conjecture is also known as the Kakutani conjecture. *Wik

1912 George Eric Deacon Alcock (August 28, 1912 – December 15, 2000)
George Alcock was an English astronomer. He was one of the most successful visual discoverers of novae and comets. He was also a very good (probably under-respected) teacher of the 4th year at Southfields Junior School in Stanground, Peterborough. In 1953 he decided to start searching for comets and in 1955 began searching for novae. His technique was to memorize the patterns of thousands of stars, so that he would visually recognize any intruder.
In 1959 he discovered comet C/1959 Q1 (Alcock), the first comet discovered in Britain since 1894, and only five days later discovered another, C/1959 Q2 (Alcock). He discovered two more comets in 1963 and 1965. He later discovered his first nova, Nova Delphini 1967 (HR Delphini), which turned out to have an unusual light curve. He discovered two more novas, LV Vul (in 1968) and V368 Sct (in 1970). He found his fifth and final comet in 1983: C/1983 H1 (IRAS-Araki-Alcock). In 1991 he found the nova V838 Her.
Alcock won the Jackson-Gwilt Medal of the Royal Astronomical Society in 1963 and Amateur Achievement Award of the Astronomical Society of the Pacific in 1981. After his death, a plaque was placed in Peterborough Cathedral in his memory. *TIA

1919 Sir Godfrey Newbold Hounsfield (28 August 1919 – 12 August 2004) English electrical engineer who shared the 1979 Nobel Prize for Physiology or Medicine (with Allan Cormack) for creation of computerised axial tomography (CAT) scanners. He originated the idea during a country walk in 1967 when he realized that the contents of a box could be reconstructed by taking readings at all angles through it. He applied the concept for scanning the brain using hundreds of X-ray beams imaging cross-sections that were reconstructed as high-resolution graphics by a computer program handling complex algebraic calculations. By 1973 his CAT scanner could produce cross-section images of a brain in 4-1/2-min, invaluable for the diagnosis of brain diseases. He later built a larger machines able to make a full body scan. *TIS

1921 Ralph Asher Alpher (February 3, 1921 – August 12, 2007) was an American cosmologist. Alpher's dissertation in 1948 dealt with a subject that came to be known as Big Bang nucleosynthesis. In a strange mathematical pun, his pre-publication of his thesis may have caused his independent role to have been minimized.
Although his name appears on the paper, Hans Bethe had no direct part in the development of the theory, although he later worked on related topics; Gamow added his name to make the author list Alpher, Bethe, Gamov, a pun on alpha, beta, gamma (α, β, γ), the first three letters of the Greek alphabet. Thus, Alpher's independent dissertation was first published on April 1, 1948 in the Physical Review with three authors. The humor engendered by the prodigious Gamow may at times have obscured the critical role Alpher played in developing the theory. This seminal paper was based on his dissertation (defended shortly thereafter).
With the award of the 2005 National Medal of Science, Alpher's original contributions (nucleosynthesis and the cosmic microwave background radiation predicition) to the modern big bang theory are beginning to receive due recognition. Neil deGrasse Tyson was instrumental in a NSF committee recommendation.
In 2005 Alpher was awarded the National Medal of Science. The citation for the award reads "For his unprecedented work in the areas of nucleosynthesis, for the prediction that universe expansion leaves behind background radiation, and for providing the model for the Big Bang theory." The medal was presented to his son Dr. Victor S. Alpher on July 27, 2007 by President George W. Bush, as his father could not travel to receive the award. Ralph Alpher died following an extended illness on August 12, 2007. He had been in failing health since falling and breaking his hip in February 2007. *Wik

1919 Sir Godfrey Newbold Hounsfield (28 Aug 1919; 12 Aug 2004) English electrical engineer who shared the 1979 Nobel Prize for Physiology or Medicine (with Allan Cormack) for creation of computerised axial tomography (CAT) scanners. He originated the idea during a country walk in 1967 when he realized that the contents of a box could be reconstructed by taking readings at all angles through it. He applied the concept for scanning the brain using hundreds of X-ray beams imaging cross-sections that were reconstructed as high-resolution graphics by a computer program handling complex algebraic calculations. By 1973 his CAT scanner could produce cross-section images of a brain in 4-1/2-min, invaluable for the diagnosis of brain diseases. He later built larger machines able to make a full body scan. *TIS

1939 John Frank Charles Kingman (28 August 1939, )worked in Statistics and made significant advances in queuing theory.
He was N. M. Rothschild and Sons Professor of Mathematical Sciences and Director of the Isaac Newton Institute at the University of Cambridge from 2001 until 2006, when he was succeeded by Sir David Wallace. He is famous for developing the mathematics of the coalescent, a theoretical model of inheritance, which is fundamental to modern population genetics. *Wik

1951 Edward Witten (born August 26, 1951) is an American theoretical physicist with a focus on mathematical physics who is a professor of Mathematical Physics at the Institute for Advanced Study at Princeton, New Jersey.
Witten is a researcher in superstring theory, a theory of quantum gravity, supersymmetric quantum field theories and other areas of mathematical physics.[1]
He has made contributions in mathematics and helped bridge gaps between fundamental physics and other areas of mathematics. In 1990 he became the first physicist to be awarded a Fields Medal by the International Union of Mathematics. In 2004, Time magazine stated that Witten was widely thought to be the world's greatest living theoretical physicist. *Wik


DEATHS

2005 George Szekeres (29 May 1911 – 28 August 2005) was a Hungarian-born mathematician who worked for most of his life in Australia on geometry and combinatorics. *SAU
Szekeres worked closely with many prominent mathematicians throughout his life, including Paul Erdős, Esther Szekeres (née Esther Klein), Paul Turán, Béla Bollobás, Ronald Graham, Alf van der Poorten, Miklós Laczkovich, and John Coates.
The so-called Happy Ending problem is an example of how mathematics pervaded George's life. During 1933, George and several other students met frequently in Budapest to discuss mathematics. At one of these meetings, Esther Klein proposed the following problem:

Given five points in the plane in general position, prove that four of them form a convex quadrilateral.

After allowing George, Paul Erdős, and the other students to scratch their heads for some time, Esther explained her proof. Subsequently, George and Paul wrote a paper (1935) that generalizes this result; it is regarded as one of the foundational works in the field of combinatorial geometry. Erdős dubbed the original problem the "Happy Ending" problem because it resulted in George and Esther's marriage in 1937.
George and Esther died within an hour of each other, on the same day, 28 August 2005, in Adelaide, Australia.*Wik

2005 Esther (Klein) Szekeres (20 February 1910 – 28 August 2005) was a Hungarian–Australian mathematician with an Erdős number of 1. She was born to Ignaz Klein in a Jewish family in Budapest, Kingdom of Hungary in 1910. As a young woman in Budapest, Klein was a member of a group of Hungarians including Paul Erdős, George Szekeres and Paul Turán that convened over interesting mathematical problems.
In 1933, Klein proposed to the group a combinatorial problem that Erdős named as the Happy Ending problem as it led to her marriage to George Szekeres in 1937, with whom she had two children.
Following the outbreak of World War II, Esther and George Szekeres emigrated to Australia after spending several years in Hongkew, a community of refugees located in Shanghai, China. In Australia, they originally settled in Adelaide before moving to Sydney in the 1960s.
In Sydney, Esther lectured at Macquarie University and was actively involved in mathematics enrichment for high-school students. In 1984, she jointly founded a weekly mathematics enrichment meeting that has since expanded into a program of about 30 groups that continue to meet weekly and inspire high school students throughout Australia and New Zealand.
In 2004, she and George moved back to Adelaide, where, on 28 August 2005, she and her husband passed away within an hour of each other *Wik

2007 Paul Beattie MacCready (29 Sep 1925, 28 Aug 2007) was an American engineer who invented not only the first human-powered flying machines, but also the first solar-powered aircraft to make sustained flights. On 23 Aug 1977, the pedal-powered aircraft, the Gossamer Condor successfully flew a 1.15 mile figure-8 course to demonstrate sustained, maneuverable manpowered flight, for which he won the £50,000 ($95,000) Kremer Prize. MacCready designed the Condor with Dr. Peter Lissamen. Its frame was made of thin aluminum tubes, covered with mylar plastic supported with stainless steel wire. In 1979, the Gossamer Albatross won the second Kremer Prize for making a flight across the English Channel. *TIS

2011 Anthony Edgar Sale (or Tony Sale) (30 January 1931 - 28 August 2011) led the construction of a Colossus computer replica at Bletchley Park, completed in 2007 *Wik
In 1994, a team led by Tony Sale began a reconstruction of a Colossus at Bletchley Park. Here, in 2006, Sale (right) supervises the breaking of an enciphered message with the completed machine. *Wik Photo


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

Monday 27 August 2018

A Graphic Method of Calculating Standard Deviation,

From a series of posts on the Standard Deviation in 2008:



I’ve always been interested in the methods of graphic solutions to equations. Fortunately, over the years Dave Renfro has been willing to keep me in mind when he runs across old journal articles and send me copies, dozens over the last few years on just this topic. So, when I found a patent for a mechanical machine that would do standard deviations, I thought there had to be a graphic method also. I set about trying to construct one, and what follows is one such method. I have confined myself to three points, but the method would generalize to any number of data values.
The first step is to plot the points on the y-axis of a coordinate grid, and draw a horizontal line through the mean of the values. The first image shows such a construction starting with the values a=7, b=2, and c=3, with the mean, M, at 4. [If images are not sharp, click on them to open a full sized image]

Clever observers will have noticed another point on the graph at (-1,4), one to the left of the mean point, M. We will use this point to square the length of the deviation of A (the distance from M to A). To Do this we make MA the mean proportional between 1 and MA2. This can be easily done by the method of similar triangles. We make a line from the point one left of M to point A to complete a right triangle. Then if we construct a perpendicular to this line at A, it will intersect the line through the mean at a new point I call AA. The distance M to AA is the square of the length MA.. we have found the square of the deviation of point A.

Now we just need to transpose this line to another graph for safekeeping where we will add it to the other squared deviations. We repeat the previous process with points B and C, and copy each of the lengths sequentially onto a line, thus finding the sum of the squares of the deviations.


There seems to be one image of the sum of the squares of the deviations added together that doesn't come up, so you can find it here



Now we employ similar triangles again to find the mean of the sum of the squares of the deviations. We need to divide the length of the sum (Origin to CC) by n=3. To do this we drop a perpendicular from one end of the line (0-CC) that is three units long. We connect the far end (CC) to the other end of the three unit line(see figure below) and then construct a parallel to O-CC one unit away from the end. By the properties of similar triangles, we know that P-MSS is the Mean of the sum of the squares (O-CC divided by three)… we have found the variance.



Now all that is left is to take the square root, and we do this by reversing the method we used to find the square of the deviations, we find the mean proportional between P-MSS and one. So we construct a point one to the left of the segment )-MSS and then bisect this new segment to find the center. Now we create a circle with a centered at this midpoint and using the MSS + 1 as a diameter. The positive distance from where this point crosses the x-axis to the point P is the standard deviation of the three points… Which I have calculated out with two decimal points accuracy…(although I used a negative sign …Oops).. .


The method would be the same, of course for any number of points.

On This Day in Math - August 27




Questions that pertain to the foundations of mathematics,
although treated by many in recent times,
still lack a satisfactory solution.
The difficulty has its main source in the ambiguity of language.

Giuseppe Peano,
Opening of the paper Arithmetices principia in which he introduced axioms for the integers.


The 239th day of the year; When expressing 239 as a sum of square numbers, 4 squares are required, which is the maximum that any integer can require; it is the largest number that needs the maximum number (9) of positive cubes (Only one other number requires nine cubes, can you find it?)

and a hundred years (+/-) ago (many people included 1 as a prime then; see more) 239 would have been a prime that is the sum of the first 14 primes; 239 = 1+2+3+5+7+11+...+37+41 *Derek Orr

239 appears in one of the earliest known geometrically converging formulas for computing Pi:
Pi/4 = 4 arctan(1/5) - arctan(1/239) *.archimedes-lab.org


EVENTS

In 413 BC, a lunar eclipse caused panic among the sailors of the Athens fleet and thus affected the outcome of a battle in the Peloponnesian War. The Athenians were ready to move their forces from Syracuse when the Moon was eclipsed. The soldiers and sailors were frightened by this celestial omen and were reluctant to leave. Their commander, Nicias, consulted the soothsayers and postponed the departure for 27 days. This delay gave an advantage to their enemies, the Syracusans, who then defeated the entire Athenian fleet and army, and killed Nicias.*TIS

1666 John Evelyn makes an on-site visit to Old St. Pauls with Christopher Wren.  "We went about to survey the general decays of that ancient and venerable church, and to set down the particulars in writing, what was fit to be done.."  Five days later the reports would be rendered meaningless by the Great London Fire.  *Lisa Jardine, Ingenious Pursuits, pgs 69-70

1760 Leonhard Euler, in his Letters to a German Princess on various topics of physics and philosophy, explains how a surveyor uses a level. As an example he asks which end of the straight line between their homes is higher. He discusses the flow of the rivers that connect their homes, but gives the wrong answer to his question. For discussion of this famous error, see Eves, Adieu, 34 *VFR

1771 Joseph Priestley finds a mint plant rejuvenates "spent" air. He had set out ten days earlier to test the rejuvenating effect of mint growing in a sealed container. He placed a candle in the covered glass and let it burn out in the presence of the mint. On the 27th he would return to the experiment and relight the candle and find, "it burned perfectly well in it." *Steven Johnson, The Invention of Air


1776 Even in the onset of the American Revolution, (Nathan Hale was executed for treason only five days before) future President John Adams, wrote of a visit to the Princeton Orrery: "Here we saw a most beautiful machine--an Orrery or planetarium constructed by Mr. Rittenhouse of Philadelphia. It exhibits almost every motion in the astronomical world."
David Rittenhouse was a renowned American astronomer, clockmaker, mathematician, surveyor, scientific instrument craftsman, and public official. Rittenhouse was a president of the American Philosophical Society; Treausrer of Pennsylvania; & the first director of the United States Mint. *Barbara Wells Sarudy

1783 Jacques A. C. Charles (for whom Charles' Law is named) and the Robert brothers launched the world's first hydrogen filled balloon on August 27, 1783, from the Champ de Mars, (now the site of the Eiffel Tower) where Ben Franklin was among the crowd of onlookers. The balloon was comparatively small, a 35 cubic metre sphere of rubberised silk, and only capable of lifting circa 9 kg (20 lb). It was filled with hydrogen that had been made by pouring nearly a quarter of a tonne of sulphuric acid onto a half a tonne of scrap iron. The hydrogen gas was fed into the balloon via lead pipes; but as it was not passed through cold water, great difficulty was experienced in filling the balloon completely (the gas was hot when produced, but as it cooled in the balloon, it contracted).
Daily progress bulletins were issued on the inflation; and the crowd was so great that on the 26th the balloon was moved secretly by night to the Champ de Mars, a distance of 4 kilometres. (This may not have been very secret as another source says there were processions of torchlights along the route.)
The balloon flew northwards for 45 minutes, pursued by chasers on horseback, and landed 21 kilometers away in the village of Gonesse where the reportedly terrified local peasants destroyed it with pitchforks or knives. *Wik

1784 One year after the Charles Flight (above) James Tytler became the first person in Britain to fly by ascending in a hot air balloon (He had made a minimal flight on 25 August in Edinburgh when his balloon rose a few feet from the ground. On the 27th he managed to reach a height of some 350 feet, traveling for half a mile between Green House on the northern edge of what is now Holyrood Park to the nearby village of Restalrig. *Wik

1798 Egyptian Institute founded by Napoleon in imitation of the Institut de France *VFR

1911 A century ago, on August 27, 1911, headlines of the New York Times announced that Martians had completed stunning feats of engineering and construction: two 1000-mile-long canals built on Mars in a two-year period.  These canals had not only been seen and sketched by astronomers, but also had been captured photographically, appearing in the photos as “the most marked features on that part of the planet”. *The Renaissance Mathematicus

1947 China (there was only one until 1949) issued four stamps honoring Confucius. [Scott #741-4]. *VFR

1993 Compaq Computer Corp. announced its Presario family of personal computers, intended to be user friendly and cheap. For $1,399, the Presario included a monitor, modem, and software to access the recently popularized online world through Prodigy and America Online. *CHM



BIRTHS

1850 Augusto Righi (27 August 1850 – 8 June 1920) was an Italian physicist and a pioneer in the study of electromagnetism. He was born and died in Bologna.
Righi was the first person to generate microwaves, and opened a whole new area of the electromagnetic spectrum to research and subsequent applications. His work L'ottica delle oscillazioni elettriche (1897), which summarised his results, is considered a classic of experimental electromagnetism. Marconi was his student. *Wik

1858 Birthdate of Giuseppe Peano (27 Aug 1858; 20 Apr 1932) early contributor to symbolic logic. Through the use of symbols, equations are more easily understood by anyone regardless of their language. For example, Peano introduced symbols to represent "belongs to the set of" and "there exists." In Arithmetics principia (1889), a pamphlet he wrote in Latin, Peano published his first version of a system of mathematical logic, giving his Peano axioms defining the natural numbers in terms of sets. In 1903, Peano unsuccessfully proposed an international, artificial language he called "Latino sine flexione." It was based on Latin without grammar. Its vocabulary comprised words from English, French, German and Latin. *TIS Thony Christie maintains that this may overstate his contribution. "I've been here before. Peano made a substantial contribution to the history of symbolic logic, especially the fact that it was his work that inspired Russell. However I think Boole, Jevons, Demorgan, Venn, McColl, Frege, Peirce, Ladd-Franklin and quite a few others who were doing symbolic logic before Peano might object to him being called its founder. To say nothing of the Stoics! "

1915 Norman Foster Ramsey (27 Aug 1915, )American physicist who shared (with Wolfgang Paul and Hans Georg Dehmelt) the 1989 Nobel Prize for Physics in 1989 for "for the invention of the separated oscillatory fields method and its use in the hydrogen maser and other atomic clocks." His work produced a more precise way to observe the transitions within an atom switching from one specific energy level to another. In the cesium atomic clock, his method enables observing the transitions between two very closely spaced levels (hyperfine levels). The accuracy of such a clock is about one part in ten thousand billion. In 1967, one second was defined as the time during which the cesium atom makes exactly 9,192,631,770 oscillations.*TIS

1923 Jacob Willem "Wim" Cohen (27 August 1923, 12 November 2000) was a Dutch mathematician, well known for over a hundred scientific publications and several books in queueing theory. *Wik

1926 Kristen Nygaard (August 27, 1926, August 10, 2002) was a Norwegian computer scientist, programming language pioneer and politician. He was born in Oslo and died of a heart attack in 2002. Internationally he is acknowledged as the co-inventor of object-oriented programming and the programming language Simula with Ole-Johan Dahl in the 1960s.



DEATHS

1898 John Hopkinson (27 Jul 1849, 27 Aug 1898)British physicist and electrical engineer who worked on the application of electricity and magnetism in devices like the dynamo and electromagnets. Hopkinson's law (the magnetic equivalent of Ohm's law) bears his name. In 1882, he patented his invention of the three-wire system (three phase) for electricity generation and distribution. He presented the principle the synchronous motors (1883), and designed electric generators with better efficiency. He also studied condensers and the phenomena of residual load. In his earlier career, he became (1872) engineering manager of Chance Brothers and Co., a glass manufacturer in Birmingham, where he studied lighthouse illumination, improving efficiency with flashing groups of lights.*TIS

1912 Mikhail Vashchenko-Zakharchenko worked on the theory of linear differential equations, the theory of probability and non-euclidean geometry.*SAU

1958 Ernest Orlando Lawrence (8 Aug 1901, 27 Aug 1958 ) American physicist who was awarded the 1939 Nobel Prize for Physics for his invention of the cyclotron, the first device for the production of high energy particles. His first device, built in 1930 used a 10-cm magnet. He accelerated particles within a cyclinder at high vacuum between the poles of an electromagnetic to confine the beam to a spiral path, while a high A.C. voltage increased the particle energy. Larger models built later created 8 x 104 eV beams. By colliding particles with atomic nuclei, he produced new elements and artificial radioactivity. By 1940, he had created plutonium and neptunium. He extended the use of atomic radiation into the fields of biology and medicine. Element 103 was named Lawrencium as a tribute to him. *TIS

1988 Max Black​ (24 February 1909, 27 August 1988) was a British-American philosopher and a leading influence in analytic philosophy in the first half of the twentieth century. He made contributions to the philosophy of language, the philosophy of mathematics and science, and the philosophy of art, also publishing studies of the work of philosophers such as Frege. His translation (with Peter Geach) of Frege's published philosophical writing is a classic text. *Wik


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