## Saturday, 21 July 2012

### On This Day in Math - July 21

The saddest aspect of life right now is that
science gathers knowledge faster than society gathers wisdom.

-Isaac Asimov

This is the 203rd  day of the year; 203 is the 6th Bell number, i.e. it is the number of partitions of a set of size 6.

EVENTS
1807 Gauss, in a letter to his friend Olbers, praised the mathematical ability of Sophie Germain. *VFR Although Gauss thought well of Germain, his replies to her letters were often delayed, and he generally did not review her work. Eventually his interests turned away from number theory,[30] and in 1809 the letters ceased. Despite the friendship of Germain and Gauss, they never met.*Wik
1820 Oersted announced his discovery of electromagnetism. *VFR The actual discovery of electromagnetism was made during a lecture demonstration that Oersted was conducting for advanced students during the spring of 1820. It is perhaps the only case known in the history of science when a major scientific discovery was mate in front of a classroom of students.

1814 Joseph von Fraunhofer was the eleventh child of an indigent glazier he was orphaned and apprenticed to Philipp Weichselberger. It may seem strange to say that he was lucky to have the dilapidated building which was the house and shop of Weichselberger collapse on top of him. But being the only survivor made him newsworthy, and when he was visited by Maximilian Joseph, the Bavarian Elector, he was given a sum of eighteen ducats with which he bought a glass making machine, books, and his freedom from his apprenticeship. Ahead in his brief life, he would discover the spectral lines which still carry his name. *Timothy Ferris, Coming of Age in the Milky Way
 The presence of dark lines in the spectrum of sunlight can be seen in his original 1814 drawing. *NASA
These dark fixed lines were later shown to be atomic absorption lines, as explained by Kirchhoff and Bunsen in 1859. These lines are still called Fraunhofer lines in his honour - although they had previously been noted by Wollaston in 1802.

1959 The ﬁrst “International Mathematical Olympiad” began in Brasov, Romania. It lasted until 31 July and involved 52 competitors on teams from seven Eastern European countries. The Romanian Team won the team event, and the individual Gold Medal went to Bohuslav Diviš from Czechoslovakia. *IMO Website

1967 Brazil (Scott #1053) issued a stamp to commemorate the 6th Brazilian Mathematical Congress. It depicted, in bright blue and black, a M¨obius strip—the ﬁrst time that this famous shape has been shown on either stamp or coin. [Journal of Recreational Mathematics, 1(1968), 44] *VFR

In 1970, the Aswan High Dam in Egypt was completed after 18 years of work. It is a huge rockfill dam that lies just north of the border between Egypt and Sudan. It captures the world's longest river, the Nile, in the world's third largest reservoir, Lake Nasser. Built with Soviet aid at a cost of \$1 billion, it now produces hydroelectricity meeting 50% of Egypt's power needs. It holds several years of irrigation reserves, assists multi-cropping, has increased productivity 20-50%, enormously increased Egypt's arable land, and overall, increased Egypt's agricultural income by 200%. The embankment is 111 metres high, with a width of near 1,000 metres. Lake Nasser is 480 long and up to 16 km wide. *TIS

In 1982, the first look at the Three Mile Island Unit 2 partial core meltdown was recorded by a mini-TV camera. This was the first inspection of the core made since the nuclear power plant in Harrisburg, Pennsylvania, first experienced a serious accident on 28 Mar 1979, due to a loss of water coolant. With the camera nothing was seen until five feet down - signifying that five feet of the core was gone. Many fuel rods had melted causing the tubes to break, spilling uranium to the bottom of the pressure vessel. Thus out of reach of the control rods, the uranium fission continued. Fifty percent of the core was destroyed or molten and an estimated twenty tons of uranium pellets had travelled to the bottom of the pressure vessel. *TIS

July 21, 1990 Meteorologist Joe Rao was able to coerce American Trans-Air Airlines to alter the course of one of their regularly scheduled flights in order to be in the right position to experience the total phase of the July 22-21, 1990 total solar eclipse. The
eclipse began on Sunday, July 22, with the path of totality passing over Helsinki, Finland. The shadow path then moved across northernmost sections of Russia, then crossed the International Date Line, causing the eclipse date to change to Saturday, July 21.
The totality track swept southeast over Alaska's Aleutian Island chain, before reaching its end at a point midway between Honolulu, Hawaii and San Francisco, California. American Trans-Air Flight 403 normally flies from Hawaii to San Francisco on Saturday afternoons. A few weeks in advance of the eclipse, Rao informed the airline that by delaying the flight by 41 minutes out of Honolulu, that Flight 403 would likely be in position to catch the total phase. The airline agreed to make the attempt, allowing most of the 360 persons on board their Lockheed L-1011 jet the opportunity to witness totality. Rao, his wife Renate, and two friends, flew out of New York's JFK airport late on Friday night, July 20 . . . arrived in San Francisco early on Saturday morning for a few hours of sleep, before boarding ATA Flight 402 to Hawaii. They were in Honolulu for 45 minutes before turning around and heading back for San Francisco (encountering the eclipse along the way). After spending the night in San Francisco, they returned to New York the next day, having traveled over 11,000 miles in 46 hours just to see 73 seconds of a total eclipse!*NSEC

BIRTHS
1620 Jean Picard (July 21, 1620 – July 12, 1682) Astronomer, born La Flêche, France. Picard is regarded as the founder of modern astronomy in France. He introduced new methods, improved the old instruments, and added new devices, such as Huygens' pendulum clock to record times and time intervals. Jean Picard was the first to put the telescope to use for the accurate measurement of small angles, making use of Gascoigne's micrometer. His most important work was the first measurement of the circumference of the earth. He used the method of Eratosthenes, but with greater accuracy. The concept behind neon signs began in 1675, when astronomer Jean Picard observed a glow in a barometer.*TIS (Dates of Birth and death are only 9 days apart)

1810 Henri-Victor Regnault (21 July 1810 – 19 January 1878) French chemist and physicist noted for his work on the properties of gases. His invaluable work was done as a skilful, thorough, patient experimenter in determining the specific heat of solids, liquids, gases, and the vapour-tensions of water and other volatile liquids, as well as their latent heat at different temperatures. He corrected Mariotte's law of gases concerning the variation of the density with the pressure, determined the coefficients of expansion of air and other gases, devised new methods of investigation and invented accurate instruments. Two laws governing the specific heat of gases are named after him.*TIS

1849 Robert Simpson Woodward (July 21, 1849–June 29, 1924) was an American physicist and mathematician, born at Rochester, Michigan. He graduated C.E. at the University of Michigan in 1872 and was appointed assistant engineer on the United States Lake Survey. In 1882 he became assistant astronomer for the United States Transit of Venus Commission. In 1884 he became astronomer to the United States Geological Survey, serving until 1890, when he became assistant in the United States Coast and Geodetic Survey. In 1893 he was called to Columbia as professor of mechanics and subsequently became professor of mathematical physics as well. He was dean of the faculty of pure science at Columbia from 1895 to 1905, when he became president of the Carnegie Institution of Washington, whose reputation and usefulness as a means of furthering scientific research was widely extended under his direction. He was elected to the National Academy of Sciences in 1896. In 1898-1900 he was president of the American Mathematical Society, and in 1900 president of the American Association for the Advancement of Science. In 1915 he was appointed to the Naval Consulting Board. He died in 1924 in Washington, D.C.
Professor Woodward carried on researches and published papers in many departments of astronomy, geodesy, and mechanics. In the course of his work with the United States Coast and Geodetic Survey he devised and constructed the "iced bar and long tape base apparatus," which enables a base line to be measured with greater accuracy and with less expense than by methods previously employed. His work on the composition and structure of the earth and the variation of latitude found expression in a number of valuable papers. *Wik (Calendar Dates of birth and death less than one month apart)

1861 Herbert Ellsworth Slaught born.(21 July 1861 in Seneca Lake, Watkins, New York, USA - 21 May 1937 in Chicago, Illinois, USA)*VFR During 1902-3 Slaught travelled in Europe attending lectures by the leading mathematicians. Perhaps he felt that he could never achieve the depth of research he was exposed to at this time for, after a worrying time of indecision, he decided that he was not cut out for a research career but could give most to the world of mathematics by concentrating on teaching.
After seeking Dickson's advice on the best way to serve the mathematical community, he accepted Dickson's suggesting of becoming co-editor of the American Mathematical Monthly. He also became active in the organisation of the Mathematical Association of America, the National Council of Teachers of Mathematics, and the Chicago section of the American Mathematical Society. He served as secretary of the last named Society from 1906 to 1916.
Bliss describes Slaught as:-... one of the men most widely known by teachers and students of mathematics... His lifelong devotion to... the promotion of the study of mathematics, his skill as a teacher, his effective leadership in the mathematical organizations which he sponsored, and his influence with teachers of mathematics the country over, were remarkable. *Wik

1880 Milan (Rastislav) Stefánik (July 21, 1880 – May 4, 1919) Slovakian astronomer and general who, with Tomás Masaryk and Edvard Benes, from abroad, helped found the new nation of Czechoslovakia by winning much-needed support from the Allied powers for its creation as a post-WWI republic, (1918-19). Before the war, the famous observatory in Meudon near Paris sent a scientific expedition to the 4810m high Mont Blanc. He joined the expedition, which was paid for by the French government to go to the roof of Europe.*TIS

1926 John Leech (July 21, 1926 in Weybridge, Surrey – 28 September 1992 in Scotland) is best known for the Leech lattice which is important in the theory of finite simple groups.*SAU  He also discovered Ta(3) in 1957. (In mathematics, the nth taxicab number, typically denoted Ta(n) or Taxicab(n), is defined as the smallest number that can be expressed as a sum of two positive algebraic cubes in n distinct ways. The concept was first mentioned in 1657 by Bernard Frénicle de Bessy, and was made famous in the early 20th century by a story involving Srinivasa Ramanujan.
$\begin{matrix}\operatorname{Ta}(3)&=&87539319&=&167^3 &+& 436^3 \\&&&=&228^3 &+& 423^3 \\&&&=&255^3 &+& 414^3\end{matrix}$
*Wik

DEATHS
1873 Delfino Codazzi (March 7, 1824 – July 21, 1873) was an Italian mathematician who worked in differential geometry.*SAU He made some important contributions to the differential geometry of surfaces, such as the Gauss–Codazzi–Mainardi equations. *Wik

1925 Giovanni Frattini (January 8, 1852 Rome – July 21, 1925, Rome) was an Italian mathematician, noted for his contributions to group theory.  In 1885 he published a paper where he defined a certain subgroup of a finite group. This subgroup, now known as the Frattini subgroup, is the subgroup Φ(G) generated by all the non-generators of the group G. He showed that Φ(G) is nilpotent and, in so doing, developed a method of proof known today as Frattini's argument.*TIS
He entered the University of Rome in 1869, where he studied mathematics with Giuseppe Battaglini, Eugenio Beltrami, and Luigi Cremona, obtaining his PhD. in 1875.*Wik

1926 Washington Roebling U.S. civil engineer under whose direction the Brooklyn Bridge, New York City, was completed in 1883. The bridge was designed by Roebling with his father, John Augustus Roebling, from whom he had gained experience building wire-rope suspension bridges. Upon his father's death, he superintended the building of the Brooklyn Bridge (1869-83). He was disabled by decompression sickness after entering a caisson in 1872. He was brought out nearly insensible and his life was saved with difficulty. Because of resulting poor health, he directed operations from his home in Brooklyn overlooking the site. Though he continued to head the family's wire-rope manufacturing business for several years, medical problems forced retirement (1888).

1937 Edwin Bailey Elliott (1 June 1851, Oxford, England - 21 July 1937 in Oxford, England)After outstanding achievements at university, Elliott became a Fellow and Mathematical Tutor of Queen's College, Oxford, in 1874.
In addition to his Fellowship at Queen's College, Elliott was appointed a lecturer in mathematics at Corpus Christi College in Oxford in 1884. These appointments came to an end in 1892 when Elliott became the first Waynflete professor of Pure Mathematics. This chair was named after William of Waynflete, the English lord chancellor and bishop of Winchester who founded Magdalen College in the 15th century. The Waynflete chair came with a Fellowship at Magdalen College so Elliott was again attached to his old College. One year after being appointed to the Waynflete Chair of Pure Mathematics, Elliot married Charlotte Amelia Mawer.
Elliott held the Waynflete chair for 29 years until his retirement in 1921. During this time he was much involved with the London Mathematical Society, being President of the Society from 1896 to 1898. A few years before this, in 1891, he had been honoured by being elected a Fellow of the Royal Society. As Chaundy writes-
Elliott's mathematical life circulated round the twin foci of Oxford and London. Besides his work in formal teaching and lecturing at Oxford, he was one of the founders (1888) of the Oxford Mathematical Society, its first secretary, and later its president.
His mathematical work included algebra, algebraic geometry, synthetic geometry, elliptic functions and the theory of convergence. However his most important contribution was the book An introduction to the algebra of quantics which was first published in 1895. This work was a major contribution to invariant theory. *SAU

1966 Francesco Cantelli (20 December 1875, Palermo – 21 July 1966, Rome) was an Italian mathematician who made contributions to the theory of probability.*SAU  He was the founder of the Istituto Italiano degli Attuari for the applications of mathematics and probability to economics.
His early papers were on problems in astronomy and celestial mechanics.
The later work was all on probability and it is in this field where his name graces the Borel–Cantelli lemma and the Glivenko–Cantelli theorem.  *Wik

1966 Philipp Frank (March 20, 1884, Vienna, Austria - July 21, 1966, Cambridge, Massachusetts, USA) was a physicist, mathematician and also an influential philosopher during the first half of the 20th century. He was a logical-positivist, and a member of the Vienna Circle.He was born on 20 March 1884 in Vienna, Austria, and died on 21 July 1966 in Cambridge, Massachusetts, USA. He studied physics at the University of Vienna and graduated in 1907 with a thesis in theoretical physics under the supervision of Ludwig Boltzmann. Albert Einstein recommended him as his successor for a professorship at the German Charles-Ferdinand University of Prague, a position which he held from 1912 until 1938. He then emigrated to the United States, where he became a lecturer of physics and mathematics at Harvard University.
Astronomer Halton Arp described Frank's Philosophy of Science class at Harvard as being his favorite elective.
He was a colleague and admirer of both Mach and Einstein. In lectures given during World War II at Harvard, Frank attributed to Mach himself the following graphic expression of "Mach's Principle":"When the subway jerks, it's the fixed stars that throw you down."
In commenting on this formulation of the principle, Frank pointed out that Mach chose the subway for his example because it shows that inertial effects are not shielded (by the mass of the earth): The action of distant masses on the subway-rider's mass is direct and instantaneous. It is apparent why Mach's Principle, stated in this fashion, does not fit with Einstein's conception of the retardation of all distant action.*Wik

1971 Yrjo Vaisala (6 September 1891 – 21 July 1971) Finnish meteorologist and astronomer regarded as the "father of space research in Finland," As early as 1946, he had suggested that geodetic triangulation at that time being done with rockets or balloons with onboard flashes could better be accomplished by artificial satellites. By the next year he was talking about artificial satellites being used for solar system exploration. In the 1950's he founded Tuorla Observatory and went on to build a tunnel under the hill at Tuorla Observatory to enable making interference measurements to accurately define the length standard for geodesy. He was outstanding in his ability to produce excellent optics for telescopes. Vaisala, together with Liisa Oterman at Tuorla, outpaced the rest of the world in their discovery of minor planets*TIS

1993 Edwin James George Pitman was born in Melbourne on 29 October 1897 and died at Kingston near Hobart on 21 July 1993.
In 1920 he completed the degree course and graduated B.A. (1921), B.Sc. (1922) and M.A. (1923). In the meantime he was appointed Acting Professor of Mathematics at Canterbury College, University of New Zealand (1922-23). He returned to Australia when appointed Tutor in Mathematics and Physics at Trinity and Ormond Colleges and Part-time Lecturer in Physics at the University of Melbourne (1924-25). In 1926 Pitman was appointed Professor of Mathematics at the University of Tasmania, a position he held until his retirement in 1962.
Pitman described himself as 'a mathematician who strayed into Statistics'; nevertheless, his contributions to statistical and probability theory were substantial.
Pitman was active in the formation of the Australian Mathematical Society in 1956. He also took an active part in the Summer Research Institutes organized by the Mathematical Society, and used them as a sounding board for his research on statistical inference.
He was a renowned member of the Statistical Society of Australia, attending its biennial conferences. In 1978 the Statistical society established the Pitman Medal.
Pitman presented the first systematic account of non-parametric inference and lectured extensively on the subject, both in Australia and in the United States. The kernel of the subject, as described by him, is 'Suppose that the sum of two samples A, B is the sample C. Then A, B are discordant if A is an unlikely sample from C.' Again, he writes, 'The approach to the subject, starting from the sample and working towards the population instead of the reverse, may be a bit of a novelty'; and later, 'the essential point of the method is that we do not have to worry about the populations which we do not know, but only about the sample values which we do know'.
The notes of the 'Lectures on Non-parametric Inference' given in the United States, though never published, have been widely circulated and have had a major impact on the development of the subject. Among the new concepts introduced in these Lectures are asymptotic power, efficacy, and asymptotic relative efficiency.
A major contribution to probability theory is his elegant treatment of the behavior of the characteristic function in the neighborhood of the origin, in three papers. This governs such properties as the existence of moments. There are also interesting properties of the Cauchy distribution, and of subexponential distributions.
On his death, on 21 July 1993, Edwin was buried at the Hobart Regional Cemetery in Kingston. He lives on in the memory of many of us who are grateful for his life and legacy.
*Evan J. Williams, Australian Academy of Science
1998 Alan (Bartlett) Shepard, Jr. (November 18, 1923 – July 21, 1998) was America's first man in space and one of only 12 humans who walked on the Moon. Named as one of the nation's original seven Mercury astronauts in 1959, Shepard became the first American into space on 5 May 1961, riding a Redstone rocket on a 15-minute suborbital flight that took him and his Freedom 7 Mercury capsule 115 miles in altitude and 302 miles downrange from Cape Canaveral, FL. (His flight came three weeks after the launch of Soviet cosmonaut Yuri Gagarin, who on 12 Apr 1961, became the first human space traveler on a one-orbit flight lasting 108 minutes.) Although the flight of Freedom 7 was brief, it was a major step for the U.S. in a race with the USSR.*TIS

Credits
*CHM=Computer History Museum
*FFF=Kane, Famous First Facts
*NSEC= NASA Solar Eclipse Calendar
*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