Monday, 16 October 2017

On This Day in Math - Oct 16

I have often pondered over the roles of knowledge or experience, on the one hand, and imagination or intuition, on the other, in the process of discovery. I believe that there is a certain fundamental conflict between the two, and knowledge, by advocating caution, tends to inhibit the flight of imagination. Therefore, a certain naivete, unburdened by conventional wisdom, can sometimes be a positive asset.
~Harish-Chandra

The 289th day of the year; 289 is a Friedman number since (8 + 9)2 = 289 (A Friedman number is an integer which, in a given base, is the result of an expression using all its own digits in combination with any of the four basic arithmetic operators (+, −, ×, ÷) and sometimes exponentiation.)Students might try to find the first few multi-digit Friedman numbers.

289 is the square of the sum of the first four primes, 289 = (2 + 3 + 5 + 7)2

289 is the largest 3-digit square with increasing digits.

289 is the hypotenuse of a primitive Pythagorean triple. Find the legs students!

EVENTS

1707 Roger Cotes elected ﬁrst Plumian Professor of Astronomy and Experimental Philosophy at Cambridge at age 26. He is best known for his meticulous and creative editing of the second edition (1713) of Newton’s Principia. He was also an important developer of the integral calculus. *Ronald Gowing, Roger Cotes, Natural Philosopher, p. 14

1797 Gauss records in his diary that he has discovered a new proof of the Pythagorean Theorem. See Gray, Expositiones Mathematicae, 2(1984), 97–130. *VFR

1819  Thomas Young writes to Fresnel to thank him for a copy of his memoirs (sent to Young by Arago). "I return a thousand thanks, Monsieur, for the gift of your admirable memoir, which surely merits a very high rank amongst the papers which have contributed most to the progress of optics." *A history of physics in its elementary branches By Florian Cajori

1843 Hamilton discovered quaternions while walking along the Royal Canal in Dublin and immediately scratches the multiplication formulas on a bridge. Today a plaque on the bridge reads, "Here as he walked by on the 16th of October 1843 Sir William Rowan Hamilton in a ﬂash of genius discovered the fundamental formula for quaternion multiplication i2 = j2 = k2 = ijk = −1 & cut it in a stone on this bridge." Since 1989, the Department of Mathematics of the National University of Ireland, Maynooth has organized a pilgrimage, where scientists (including the physicists Murray Gell-Mann in 2002, Steven Weinberg in 2005, and the mathematician Andrew Wiles in 2003) take a walk from Dunsink Observatory to the Royal Canal bridge where no trace of Hamilton's carving remains, unfortunately.
Here is how Hamilton described his memory of the discovery of the Quaternions to his son, "Every morning in the early part of the above-cited month, on my coming down to breakfast, your (then) little brother, William Edwin, and yourself, used to ask me, Well, papa, can you multiply triplets?' Whereto I was always obliged to reply, with a sad shake of the head: No, I can only add and subtract them. But on the 16th day of the same month (Oct) - which happened to be Monday, and a Council day of the Royal Irish Academy - I was walking in to attend and preside, and your mother was walking with me along the Royal Canal, to which she had perhaps driven; and although she talked with me now and then, yet an undercurrent of thought was going on in my mind which gave at last a result, whereof it is not too much to say that I felt at once the importance. An electric circuit seemed to close; and a spark flashed forth the herald (as I foresaw immediately) of many long years to come of definitely directed thought and work by myself, if spared, and, at all events, on the part of others if I should even be allowed to live long enough distinctly to communicate the discovery. Nor could I resist the impulse - unphilosophical as it may have been - to cut with a knife on a stone of Brougham Bridge, as we passed it, the fundamental formula which contains the Solution of the Problem, but, of course, the inscription has long since mouldered away. A more durable notice remains, however, on the Council Books of the Academy for that day (October 16, 1843), which records the fact that I then asked for and obtained leave to read a Paper on Quaternions,' at the First General Meeting of the Session; which reading took place accordingly, on Monday, the 13th of November following.'' *from Hamilton By Sir Robert Stawell Ball.

The plaque says:
Here as he walked by
on the 16th of October 1843
Sir William Rowan Hamilton
in a flash of genius discovered
the fundamental formula for
quaternion multiplication
i2 = j2 = k2 = i j k = −1
& cut it on a stone of this bridge

(Quatenion was a Latin term before Hamilton used it.  Milton uses it in Paradise Lost to refer to the four elements of antiquity: air, earth, water, and fire. The last three are “the eldest birth of nature’s womb” because they are mentioned in Genesis before air is mentioned. *John Cook )

In 1982, Halley's Comet was observed on its 30th recorded visit to Earth, first detected using the 5-m (200-in) Hale Telescope at the Mount Palomar Observatory by a team of astronomers led by David Jewett and G. Edward Danielson. They found the comet, beyond the orbit of Saturn, about 11 AU (1.6 billion km) from the Sun. While 50 million times fainter than the faintest objects our eyes can see, they needed to use not only the largest American telescope but also special electronic equipment developed for the Space Telescope. In 1705, Halley used Newton's theories to compute the orbit and correctly predicted the return of this comet about every 76 years. After his death, for correctly predicting its reappearance, it was named after Halley. *TIS (The next predicted perihelion of Halley's Comet is 28 July 2061)
In 1982 the first image of the returning Halley's Comet was recorded with the 200-inch Hale telescope at Palomar Mountain. Caltech astronomers David Jewitt and G. Edward Danielson found the comet when it was still beyond the orbit of Saturn, more than 1.6 billion kilometers (960 million miles) from the Sun. *National Air and Space Museum

1988 Connect Four Solved first by James D. Allen (Oct 1, 1988), and independently by Victor Allis (Oct 16, 1988). First player can force a win. Strongly solved by John Tromp's 8-ply database (Feb 4, 1995). Weakly solved for all boardsizes where width+height is at most 15 (Feb 18, 2006). *Wik

2016 The 27th Hamilton walk takes place on this day. Students, professors, and math lovers in general will gather at the Dunsink Observatory around 3:30 pm and proceed to Broombridge in Cabra where he had his Eureka moment about Quaternions. (see 1843 in Events above) The annual event is part of Irish Math week.

BIRTHS
1689 Robert Smith (16 October,1689 – 2 February, 1768) was an English mathematician and Master of Trinity College.
Smith was probably born at Lea near Gainsborough, the son of the rector of Gate Burton, Lincolnshire. He entered Trinity College, Cambridge, in 1708, and becoming minor fellow in 1714, major fellow in 1715 and senior fellow in 1739. From 1716 to 1760 he was Plumian Professor of Astronomy,and was chosen Master in 1742, in succession to Richard Bentley.
Besides editing two works by his cousin, Roger Cotes, who was his predecessor in the Plumian chair, he published A Compleat System of Opticks in 1738, (which was the principal textbook on Optics in the 18th Century) , and Harmonics, or the Philosophy of Musical Sounds in 1749.
Smith never married but lived with his unmarried sister Elzimar (1683–1758) in the lodge at Trinity College. Although he is often portrayed as a rather reclusive character, John Byrom's journal shows that in the 1720s and 1730s Smith could be quite sociable. Yet ill health, particularly gout, took its toll and severely inhibited his academic work and social activities. He died at the lodge on 2 February 1768, and on 8 February he was buried in Trinity College Chapel.
In his will Smith left £3500 South Sea stock to the University of Cambridge. The net income on the fund is annually divided equally between the Smith's Prize and the stipend of the Plumian Professor. *Wik

1879 Philip Edward Bertrand Jourdain (16 October 1879 – 1 October 1919) was a British logician and follower of Bertrand Russell. He corresponded with Georg Cantor and Gottlob Frege, and took a close interest in the paradoxes related to Russell's paradox, formulating the card paradox version of the liar paradox. He also worked on algebraic logic, and the history of science with Isaac Newton as a particular study. He was London editor for The Monist. *Wik

1882 Ernst Erich Jacobsthal (16 October 1882, Berlin – 6 February 1965, Überlingen) was a German mathematician, and brother to the archaeologist Paul Jacobsthal.
In 1906, he earned his PhD at the University of Berlin, where he was a student of Georg Frobenius, Hermann Schwarz and Issai Schur; his dissertation, Anwendung einer Formel aus der Theorie der quadratischen Reste (Application of a Formula from the Theory of Quadratic Remainders), provided a proof that prime numbers of the form 4n + 1 are the sum of two square numbers. *Wik

1930 John Charlton Polkinghorne KBE FRS (born 16 October 1930) is an English theoretical physicist, theologian, writer, and Anglican priest. He was professor of Mathematical physics at the University of Cambridge from 1968 to 1979, when he resigned his chair to study for the priesthood, becoming an ordained Anglican priest in 1982. He served as the president of Queens' College, Cambridge from 1988 until 1996.*Wik

DEATHS

1937 William Sealy Gosset (13 June 1876 in Canterbury, England - 16 October 1937 in Beaconsfield, England) Gosset was the eldest son of Agnes Sealy Vidal and Colonel Frederic Gosset who came from Watlington in Oxfordshire. William was educated at Winchester, where his favourite hobby was shooting, then entered New College Oxford where he studied chemistry and mathematics. While there he studied under Airy. He obtained a First Class degree in both subjects, being awarded his mathematics degree in 1897 and his chemistry degree two years later.

Gosset obtained a post as a chemist with Arthur Guinness Son and Company in 1899. Working in the Guinness brewery in Dublin he did important work on statistics. In 1905 he contacted Karl Pearson and arranged to go to London to study at Pearson's laboratory, the Galton Eugenics Laboratory, at University College in session 1906-07. At this time he worked on the Poisson limit to the binomial and the sampling distribution of the mean, standard deviation, and correlation coefficient. He later published three important papers on the work he had undertaken during this year working in Pearson's laboratory.
Many people are familiar with the name "Student" but not with the name Gosset. In fact Gosset wrote under the name "Student" which explains why his name may be less well known than his important results in statistics. He invented the t-test to handle small samples for quality control in brewing. Gosset discovered the form of the t distribution by a combination of mathematical and empirical work with random numbers, an early application of the Monte-Carlo method.

McMullen says:-

To many in the statistical world "Student" was regarded as a statistical advisor to Guinness's brewery, to others he appeared to be a brewer devoting his spare time to statistics. ... though there is some truth in both these ideas they miss the central point, which was the intimate connection between his statistical research and the practical problems on which he was engaged. ... "Student" did a very large quantity of ordinary routine as well as his statistical work in the brewery, and all that in addition to consultative statistical work and to preparing his various published papers.

From 1922 he acquired a statistical assistant at the brewery, and he slowly built up a small statistics department which he ran until 1934.
Gosset certainly did not work in isolation. He corresponded with a large number of statisticians and he often visited his father in Watlington in England and on these occasions he would visit University College, London, and the Rothamsted Agricultural Experiment Station. He would discuss statistical problems with Fisher, Neyman and Pearson. *SAU

1983 Harish-Chandra (11 October 1923 – 16 October 1983) was an Indian mathematician, who did fundamental work in representation theory, especially Harmonic analysis on semisimple Lie groups.*Wik

1998 Jonathan Bruce Postel (6 Aug 1943, 16 Oct 1998) American computer scientist who played a pivotal role in creating and administering the Internet. In the late 1960s, Postel was a graduate student developing the ARPANET, a forerunner of the Internet for use by the U.S. Dept. of Defense. As director of the Internet Assigned Numbers Authority (IANA), which he formed, Postel was a creator of the Internet's address system. The Internet grew rapidly in the 1990s, and there was concern about its lack of regulation. Shortly before his death, Postel submitted a proposal to the U.S. government for an international nonprofit organization that would oversee the Internet and its assigned names and numbers. He died at age 55, from complications after heart surgery.*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

Sunday, 15 October 2017

On This Day in Math - October 15

Many have argued that a vacuum does not exist, others claim it exists only with difficulty in spite of the repugnance of nature; I know of no one who claims it easily exists without any resistance from nature.
— Evangelista Torricelli in a Letter to Michelangelo Ricci

The 288th day of the year; 288 is the super-factorial of four. 1! x 2! x 3! x 4! =288. It is important that math students learn not to say this number in public as it is two gross. (I apologize for the really bad pun)

288 is also the sum of the first four integers raised to their own power $1^1 + 2^2 + 3^3 + 4^4 = 288$

288 is the smallest non-palindrome, non-square, that when multiplied by its reverse is a square: 288 x 882 = 254,016 = 5042.

EVENTS

1582 St Theresa of Avila died overnight on the night between the 4th and the 15th of October. On that day the Gregorian calendar went into effect in Spain and the day after the 4th, was the 15th in order to catch up for the misalignment of the Julian Calendar. *VFR

1698 King William III commissioned Edmund Halley as Royal Naval Captain of the HMS
Paramore and provided him with a complete set of instructions. The Admiralty’s instructions to Halley dated 15 October 1698 were :
Whereas his Maty. has been pleased to lend his Pink the Paramour for your proceeding with her on an Expedition, to improve the knowledge of the Longitude and variations of the Compasse, which Shipp is now compleatly Man’d, Stored and Victualled at his Mats. Charge for the said Expedition ... *Lori L. Murray, The Construction of Edmond Halley’s 1701 Map of Magnetic Declination

1783 The ﬁrst manned ascension in a balloon. After the ﬂight of September 19, 1783, Louis XVI forbade men to go aloft, making the adventurers furious. Later he extended the privilege to convicts, ﬁguring they were expendable. de Rozier’s loud fulmigations against such glory for “vile criminals” soon changed the king’s mind. The hydrogen balloon, Aerostat Reveillon, carrying Pilâtre, first man to leave the earth, rose to the end of its 250- ft tether. It stayed aloft for 15 minutes, then landed safely nearby.
On 21 Nov 1783, untethered, Pilâtre and Marquis d'Arlande made the first manned free flight, across Paris. On 15 Jun 1785, Pilâtre attempt the first east-to-west crossing of the English Channel with a hybrid balloon combining lift from both hydrogen and hot air. Within minutes of launch, the craft exploded, and plunged to the rocks on the coast of Wimereux. Neither Pilâtre nor his co-pilot, Romain, survived the crash. *TIS (American Scientist and U S emissary to the court of Louis XVI, Ben Franklin, was present for some of the Balloon ascensions in 1783. When asked what was the use of Ballooning, he replied, “Of what use is a newborn baby?”)

In 1827, Charles Darwin was accepted into Christ's College at Cambridge, but did not start until winter term because he needed to catch up on some of his studies. A grandson of Erasmus Darwin of Lichfield, and of Josiah Wedgwood, he had entered the University of Edinburgh in 1825 to study medicine, intending to follow his father Robert's career as a doctor. However, Darwin found himself unenthusiastic about his studies, including that of geology. Disappointing his family that he gave up on a medical career, he left Edinburgh without graduating in April 1827. His scholastic achievements at Cambridge were unremarkable, but after graduation, Darwin was recommended by his botany professor to be a naturalist to sail on HM Sloop Beagle. *TIS

1956 The first FORTRAN reference manual is released on October 15, 1956, six months before the first compiler's release. Only 60 pages long, with large print and wide margins, that first programming language was miniscule by today's standard. The original FORTRAN development team comprised John Backus, Sheldon Best, Richard Goldberg, Lois Mitchell Haibt, Harlan Herrick, Grace Mitchell, Robert Nelson, Roy Nutt, David Sayre, Peter Sheridan, and Irving Ziller.*CHM

In 2003, China became the third nation to send a man into space. Lieutenant Colonel Yang Liwei, 38, was launched on a Long March CZ-2F rocket in the Shenzhou-5 spacecraft at 9 am local time (1 am GMT). He completed 14 Earth orbits during a 21-hour flight which ended with a parachute-assisted landing in the on the grasslands of Inner Mongolia in northern China. The Shenzhou spacecraft was based on the three-seat Russian Soyuz capsule, but with extensive modifications. The country began planning manned spaceflight in 1992. Russia began providing advice on technology and astronaut training in 1995. The first of four unmanned test flights of a Shenzhou craft (took place in Nov 1999. The name Shenzhou translates as "divine vessel." *TIS

BIRTHS

1608 Evangelista Torricelli (15 Oct 1608; 25 Oct 1647) Born in Faenza, Italy, Torricelli was an Italian physicist and mathematician who invented the barometer and whose work in geometry aided in the eventual development of integral calculus. Inspired by Galileo's writings, he wrote a treatise on mechanics, De Motu ("Concerning Movement"), which impressed Galileo. He also developed techniques for producing telescope lenses. The barometer experiment using "quicksilver" filling a tube then inverted into a dish of mercury, carried out in Spring 1644, made Torricelli's name famous. The Italian scientists merit was, above all, to admit that the effective cause of the resistance presented by nature to the creation of a vacuum (in the inverted tube above the mercury) was probably due to the weight of air. *TIS He succeeded his teacher, Galileo as professor of mathematics at Florence. One of his most amazing discoveries was a solid which had inﬁnite length but ﬁnite volume. He also invented the mercury barometer.*VFR

1735 Jesse Ramsden FRSE (15 October 1735 – 5 November 1800) was an English astronomical and scientific instrument maker.
Ramsden created one of the first high-quality dividing engines. This machine permitted the automatic and highly accurate division of a circle into degrees and fractions of degrees of arc.The machine  led to mass production of precision octants and sextants and gave British manufacturers dominance in the field of marine instruments for decades.  His invention was so valuable to the nation’s maritime interests that he received a share of the Longitude Prize.
His most celebrated work was a 5-feet vertical circle, which was finished in 1789 and was used by Giuseppe Piazzi at Palermo in constructing his catalog of stars. He was the first to carry out in practice a method of reading off angles (first suggested in 1768 by the Duke of Chaulnes) by measuring the distance of the index from the nearest division line by means of a micrometer screw which moves one or two fine threads placed in the focus of a microscope.
Ramsden's transit instruments were the first which were illuminated through the hollow axis; the idea was suggested to him by Prof. Henry Ussher in Dublin. He published a Description of an Engine for dividing Mathematical Instruments in 1777.
Ramsden is also responsible for the achromatic eyepiece named after him, and also worked on new designs of electrostatic generators. He was elected to the Royal Society in 1786. The exit pupil of an eyepiece was once called the Ramsden disc in his honour. In 1791 he completed the Shuckburgh telescope, an equatorial mounted refractor telescope.
In about 1785, Ramsden provided a new large theodolite for General William Roy of the Royal Engineers, which was used for a new survey of the distance between Greenwich, London and Paris. This work provided the basis for the subsequent Ordnance Survey of the counties of Britain. For his part with Roy in this work he received the Copley Medal in 1795. He died five years later at Brighton, England.*Wik

1745 George Atwood (Baptized October 15, 1745, Westminster,London – 11 July 1807, London) was an English mathematician who invented a machine for illustrating the effects of Newton's first law of motion. He was the first winner of the Smith's Prize in 1769. He was also a renowned chess player whose skill for recording many games of his own and of other players, including François-André Danican Philidor, the leading master of his time, left a valuable historical record for future generations.
He attended Westminster School and in 1765 was admitted to Trinity College, Cambridge. He graduated in 1769 with the rank of third wrangler and was awarded the inaugural first Smith's Prize. Subsequently he became a fellow and a tutor of the college and in 1776 was elected a fellow of the Royal Society of London.
In 1784 he left Cambridge and soon afterwards received from William Pitt the Younger the office of patent searcher of the customs, which required but little attendance, enabling him to devote a considerable portion of his time to mathematics and physics.
He died unmarried in Westminster at the age of 61, and was buried there at St. Margaret's Church. Over a century later, a lunar crater was renamed Atwood in his honour. *Wik

1776 Peter Barlow (15 Oct 1776, 1 March 1862) Peter Barlow was self-educated but this education was sufficiently good that he was able to compete successfully to became an assistant mathematics master at the Royal Military Academy at Woolwich. He was appointed to the post in 1801 and he began publishing mathematical articles in the Ladies Diary and he became sufficiently well established as a leading authority on mathematics that after a while he was asked to contribute various articles on mathematics for encyclopedias.
In addition to these articles, Barlow also published several important books, for example in 1811 he published An elementary investigation of the theory of numbers and three years later he published A new mathematical and philosophical dictionary.
He is remembered most for two important contributions. In 1814 he produced a second book, in addition to the one described above, entitled New mathematical tables. These soon became known as Barlow's Tables and this work gives factors, squares, cubes, square roots, reciprocals and hyperbolic logarithms of all numbers from 1 to 10 000. The book "...was considered so accurate and so useful that it has been regularly reprinted ever since. "
In the mathematical library at the University of St Andrews we have several well worn copies of these tables which must have been used intensely for many years. Today, however, they are only of historical interest since they were made completely obsolete by calculators and computers.
Barlow's second major contribution makes his name still well known by amateur astronomers today. He invented the Barlow lens, a telescope lens consisting of a colorless liquid between two pieces of glass, the "Barlow lens", a modification of this telescope lens, is a negative achromatic combination of flint glass and crown glass.
In 1819 Barlow began work on the problem of deviation in ship compasses caused by the presence of iron in the hull. For his method of correcting the deviation by juxtaposing the compass with a suitably shaped piece of iron, he was awarded the Copley Medal ... *SAU
Barlow is quoted on SAU as saying, "230(231-1) is the greatest perfect number that will ever be discovered, for, as they are merely curious without being useful, it is not likely that any person will attempt to find a number beyond it."

1829 Asaph Hall (15 Oct 1829; 22 Nov 1907) American astronomer, discovered and named the two moons of Mars, Phobos and Deimos, and calculated their orbits.Born in Goshen, Conn. and apprenticed as a carpenter at age 16, he had a passion for geometry and algebra. Hall obtained a position at the Harvard Observatory in Cambridge, Mass. in 1857 and became an expert computer of orbits. In August 1862, he joined the staff of the Naval Observatory in Washington, D.C. where he made his discoveries, in mid- Aug 1877, using the Observatory's 26-inch "Great Equatorial" refracting telescope, then the largest of its kind in the world. He stayed there 30 years until 1891. His son, Asaph Hall, Jr., followed him and worked at the Observatory at various times between 1882-1929.*TIS

1837 Leo Königsberger (15 October 1837 – 15 December 1921) was a German mathematician, and historian of science. He is best known for his three-volume biography of Hermann von Helmholtz, which remains the standard reference on the subject. The biography of Helmholtz was published in 1902 and 1903. He also wrote a biography of C. G. J. Jacobi.
Königsberger's own research was primarily on elliptic functions and differential equations. He worked closely with Lazarus Fuchs, a childhood friend.*Wik

1867 Jacques Inaudi (October 15, 1867 – November 10, 1950) Born to a poor family in the Italian Piedmont, Jacques Inaudi began life as a shepherd but soon discovered a prodigious talent for calculation, and soon he was giving exhibitions in large cities.
Camille Flammarion wrote, “He was asked, for example, how many minutes have elapsed since the birth of Jesus Christ, or what the population would be if the dead from the past ten centuries were resurrected, or the square root of a number of twelve digits, and he gave the response accurately and in two or three minutes — while amusing himself with another activity.”
“The subtraction of numbers consisting of twenty-four figures is an easy matter for him,” reported Scientific American. “Problems for which logarithm tables are generally used he solves mentally with wonderful precision.”
Unlike other prodigies, Inaudi did not visualize his work. “I hear the figures,” he told Alfred Binet, “and it is my ear which retains them; I hear them resounding after I have repeated them, and this interior sensation remains for a long time.”
Inaudi’s father had approached Flammarion hoping that his son could be educated toward a career in astronomy. “It had been an error, whichever way one looked at it,” Flammarion wrote 10 years later. “In science, one cannot make use of his methods, of his adapted formulae, which are tailored to mental calculation.” It was just as well: “Regarding his financial position, he now has, as a result of the curiosity his ability has aroused, a salary, which is over three times that of the Director of the Paris Observatory.” *Greg Ross, Futility Closet

1905 Baron C(harles) P(ercy) Snow (15 Oct 1905; 1 Jul 1980) British former physicist, turned novelist and government administrator. In 1959, C.P. Snow gave a controversial lecture called The Two Cultures and the Scientific Revolution claiming there were two cultures - the literary intellectuals and the scientists, who didn't understand each other and didn't trust each other. The split was not new; Snow noted that in the 1930s, literary theorists had begun to use the word "intellectual" to refer only to themselves. He illustrated this gap by asking a group of literary intellectuals to tell him about the Second Law of Thermodynamics, which he called the scientific equivalent of Have you read a work of Shakespeare?'" Since then, debate about this polarization has continued.*TIS

1875 André-Louis Cholesky (October 15, 1875 – August 31, 1918,) 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

Bernhard Hermann Neumann (15 Oct 1909, 21 Oct 2002) Neumann is one of the leading figures in group theory who has influenced the direction of the subject in many different ways. While still in Berlin he published his first group theory paper on the automorphism group of a free group. However his doctoral thesis at Cambridge introduced a new major area into group theory research. In his thesis he initiated the study of varieties of groups, that is classes of groups defined which are by a collection of laws which must hold when any group elements are substituted into them. *SAU
(check the dates of birth and death between this entry and the next... I checked, it seems to be correct, PB)

1909 Jesse L. Greenstein (15 Oct 1909; 21 Oct 2002) American astronomer who was a co-discoverer of quasars. His interest in astronomy began at age 8 when his grandfather gave him a brass telescope. By age 16, he was a student at Harvard University, and later earned his Ph.D.(1937), then joined the Yerkes Observatory under Otto Struve. Thereafter, he spent most of his career at the California Institute of Technology.. He measured the composition of stars, through which he found less heavy elements in the stars of globular clusters, thus proving they are younger than our Sun. In 1963, he and Maarten Schmidt were the first to correctly describe the nature of quasars, by interpreting their red shift as compact, very distant and thus very old objects. With Louis Henyey he designed and constructed a new spectrograph and wide-view camera to improve astronomical observations. *TIS

DEATHS

1959 Lipót Fejér (9 Feb 1880, 15 Oct 1959) Fejér's main work was in harmonic analysis working on Fourier series and their singularities. Fejér collaborated to produce important papers with Carathéodory on entire functions and with Riesz on conformal mappings. *SAU

1965 Abraham Halevi (Adolf) Fraenkel (February 17, 1891, Munich, Germany – October 15, 1965, Jerusalem, Israel) known as Abraham Fraenkel, was an Israeli mathematician born in Germany. He was an early Zionist and the first Dean of Mathematics at the Hebrew University of Jerusalem. He is known for his contributions to axiomatic set theory, especially his addition to Ernst Zermelo's axioms which resulted in Zermelo–Fraenkel axioms.*Wik

1980 Mikhail Alekseevich Lavrentev(19 Nov 1900 in Kazan, Russia, 15 Oct 1980 in Moscow) is remembered for an outstanding book on conformal mappings and he made many important contributions to that topic.*SAU

1990 Wilhelm Magnus (February 5, 1907, Berlin, Germany – October 15, 1990, New York City) made important contributions in combinatorial group theory, Lie algebras, mathematical physics, elliptic functions, and the study of tessellations.*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

Saturday, 14 October 2017

On This Day in Math - October 14

An expert problem solver must be endowed with two incompatible qualities, a restless imagination and a patient pertinacity.

Howard W. Eves, Mathematical Circles, Boston

The 287th day of the year; 287 is not prime, but it is the sum of three consecutive primes (89 + 97 + 101), and also the sum of five consecutive primes (47 + 53 + 59 + 61 + 67), and wait, it is also the sum of nine consecutive primes (17 + 19 + 23 + 29 + 31 + 37 + 41 + 43 + 47).

287 is the smallest non-prime Kynea number, an integer of the form 4n + 2n − 1, studied by Cletus Emmanuel who named them after a baby girl. The binary expression of these numbers is interesting, 287[2] is 100011111. Each Kynea number has a one, followed by n-1 zeros, followed by n+1 ones. The Keyna primes are all two less than a square number. There are four year days that are Kynea numbers, but 287 is the only one that is composite.

EVENTS
1608 Two weeks after Hans Lippershey applied for a patent for his "distance seeing instrument" a was note made in the meeting of the board of the province of Zeeland, on stating that an unnamed person [the clerck has not filled in his name] also claimed to have ‘the art of making an instrument to see far away objects near by’. Within days a third person,Jacob Adriaensz [Metius] of Alkmaar, the son of one of the most prominent engineers of the Dutch Republic, would claim to posses the knowledge.
Lippershey, on request of the council to develop his instrument to be used with both eyes, delivered the first binocular instrument in mid-December1608, and the other two in February
1609. All three instruments were considered to be working satisfactorily by the deputies
of the States General who had tested the instruments. The amount of 900 guilders Lippershey
received for his three instruments was large enough for him to buy his neighbor’s house in Middelburg, which he appropriately named ‘The Three Telescopes’ (the ‘Dry Vare Gesichten’). *Huib J. Zuidervaart, The ‘true inventor’ of the telescope. A survey of 400 years of debate, Royal Netherlands Academy of Arts and Sciences, Amsterdam 2010

1806 The French, under Napoleon, defeated the Prussians in the Battle of Jena. Killed was the Duke of Brunswick, patron of Gauss. *VFR

1863 Alfred Nobel was granted his first patent, a Swedish patent for the preparation of nitroglycerin. The end of the Crimean War (1856) brought bankruptcy for his father, Immanuel Nobel, whose factory manufactured war materiel. Studying chemistry, Alfred learned of the powerful new explosive, nitroglycerine. Around 1860, Alfred conducted repeated experiments involving great risks. He succeeded in manufacturing sufficient quantities of nitroglycerine without any mishaps. His father had been making similar experiments, but with less success. When his father realized his son's greater discoveries, he assisted Alfred patent the explosive that he aptly called "blasting oil." Later, in 1868, Nobel patented dynamite as a form for safer handling.*TIS

In 1885, after 15-year-old Jean Baptiste Jupille was severely bitten while with his bare hands he killed an attacking rabid dog to protect five other young shepherds in Villers-Farley, France. He shortly became the second person treated by Louis Pasteur's experimental vaccine for rabies. He was fortunate to be taken to Pasteur's laboratory. Pasteur's collaborator Emile Roux had thought of attenuating the power of the infection by exposing strips of fresh spinal marrow taken from a rabbit that had died of rabies to dry, sterile air for various lengths of time. The vaccine was a small piece of marrow ground up and suspended in sterilized broth. It had first been used on Joseph Meister on 6 Jul 1885. By 12 Apr 1886, 726 people had been treated.*TIS

1913 In letter to George Hale, Einstein sketched Sun's deflection of starlight (to be tested in eclipse) but got angle wrong (later revised)
*Paul Halpern‏ @phalpern

1947 Captain Charles E. Yeager was the ﬁrst pilot to exceed the speed of sound, ﬂying the exper-imental Bell XS-1 rocket-propelled research plane at Mach 1.06 (700 mph or 1,127 kph) at 43,000 feet. Previously, many felt that turbulence would prevent planes from breaking the sound barrier. *VFR

In 1960, the 4th legal definition of the meter was made to be 1,650,763.73 wavelengths in vacuum of the orange-red light radiation of the krypton-86 atom (transition between levels 2p10 and 5d5). This was now 100 times more accurate than the previous 3rd legal definition adopted in 1889. *TIS

BIRTHS
1687 Robert Simson (14 October 1687 – 1 October 1768) was a Scottish mathematician and professor of mathematics at the University of Glasgow. The pedal line of a triangle is sometimes called the "Simson line" after him. Edmond Halley suggested to him that he might devote his considerable talents to the restoration of the work of the early Greek geometers, such as Euclid and Apollonius of Perga These are works that only survive in abbreviated accounts given by later mathematicians such as Pappus of Alexandria. He first studied Euclid's so-called porisms. Playfair's 1792 definition of porism is "a proposition affirming the possibility of finding such conditions as will render a certain problem indeterminate, or capable of innumerable solutions."
Simson's work on Euclid's porisms was published in 1723 in the Philosophical Transactions of the Royal Society, and his restoration of the Loci Plani of Apollonius appeared in 1749. Further work of his on porisms and other subjects including logarithms was published posthumously in 1776 by Lord Stanhope at his own expense. Simson also set himself the task of preparing an edition of Euclid's Elements in as perfect a form as possible, and his edition of Euclid's books 1-6, 11 and 12 was for many years the standard text and formed the basis of textbooks on geometry written by other authors. The work ran through more than 70 different editions, revisions or translations published first in Glasgow in 1756, with others appearing in Glasgow, Edinburgh, Dublin, London, Cambridge, Paris and a number of other European and American cities. Recent editions appeared in London and Toronto in 1933 under the editorship of Isaac Todhunter and in São Paolo in 1944. Simson's lectures were delivered in Latin, at any rate at the beginning of his career. His most important writings were written in that language, however, his edition of Euclid, after its first publication in Latin, appeared in English, as did a treatise on conic sections that he wrote for the benefit of his students.
the Simson line does not appear in his work but Poncelet in Propriétés Projectives says that the theorem was attributed to Simson by Servois in the Gergonne's Journal. It appears that the theorem is due to William Wallace.
The University of St Andrews awarded Simson an honorary Doctorate of Medicine in 1746.
In 1753 Simson noted that, as the Fibonacci numbers increased in magnitude, the ratio between adjacent numbers approached the golden ratio, whose value is
(1 + √5)/2 = 1.6180 . . . . *SAU

1801 physicist J. Plateau (14 October 1801 – 15 September 1883)  Plateau’s problem asks for the minimal surface through a given curve in three dimensions. A minimal surface is the surface through the curve with the least area. Mathematically the problem is still unsolved, but physical solutions are easy: dip a curved wire in a soap solution. The “soap bubble” that results is the minimal surface for that curve. *VFR Jesse Douglas found a solution holding for an arbitrary simple closed curve. He was awarded the (one of the first two) Fields Medal in 1936 for his efforts.

In 1829 Joseph Plateau submitted his doctoral thesis to his mentor Adolphe Quetelet for advice. It contained only 27 pages, but formulated a great number of fundamental conclusions. It contained the first results of his research into the effect of colors on the retina (duration, intensity and color), his mathematical research into the intersections of revolving curves (locus), the observation of the distortion of moving images, and the reconstruction of distorted images through counter revolving
discs Prior to going blind was the first person to demonstrate the illusion of a moving image. To do this he used counter rotating disks with repeating drawn images in small increments of motion on one and regularly spaced slits in the other. He called this device of 1832 the phenakistoscope.
Plateau has often been termed a "martyr for science". . In many (popular) publications the blindness of Plateau is ascribed to his experiment of 1829 in which he looked directly into the sun for 25 seconds. Recent research definitely refutes this. The exact date of the blindness is difficult to formulate simply. It was a gradual process during the year 1843 and early 1844. Plateau publishes two papers in which he painstakingly describes the scientific observations of his own blindness. After 40 years of blindness he still has subjective visual sensations. For his experiments, as well as for the related deskwork colleagues and family help him. *Wik

1868 Alessandro Padoa​ (14 October 1868 – 25 November 1937) was an Italian mathematician and logician, a contributor to the school of Giuseppe Peano. He is remembered for a method for deciding whether, given some formal theory, a new primitive notion is truly independent of the other primitive notions. There is an analogous problem in axiomatic theories, namely deciding whether a given axiom is independent of the other axioms.*Wik

1890 Birth of Dwight D. Eisenhower. In high school, the math teacher took away Ike’s geometry book, telling him to work out the problems without beneﬁt of the book. Eisenhower was told that unless the experiment was terminated by the teacher, he would receive an A+ in the course. “Strangely enough, I got along fairly well.” Wrote Eisenhower later. [From In Review: Pictures I’ve Kept by Dwight D. Eisenhower, 1969, p. 7]. (Morris Bishop, in a footnote to his biography of Pascal, makes an even stronger claim; he says Eisenhower was told to “construct his own geometry”.) *VFR

1900 W. Edwards Deming (14 Oct 1900; died 20 Dec 1993) was an American statistician, the father of "Total Quality Management." After WW II, he contributed to Japan's economic recovery by recommending statistical methods of quality control in industrial production. His method embraced carefully tallying product defects, examining their causes, correcting the problems, and then tracking the results of these changes on subsequent product quality. In his career before the war, he had developed statistical sampling techniques that were first used in the 1940 U.S. census. From the 1980's in the U.S. Deming taught quality control through the statistical control of manufacturing processes for companies such as Ford, Xerox, and GM.*TIS

DEATHS
1940 Heinrich Kayser (16 Mar 1853, 14 Oct 1940) Heinrich (Gustav Johannes) Kayser was a German physicist who discovered the presence of helium in the Earth's atmosphere. Prior to that scientists had detected helium only in the sun and in some minerals. Kayser's early research work was on the properties of sound. In collaboration with the physicist and mathematician Carl D.T. Runge, Kayser carefully mapped the spectra of a large number of elements. He wrote a handbook of spectroscopy (1901–12) and a treatise on the electron theory (1905).*TIS

1956 Jules Richard (12 August 1862 in Blet, France- 14 October 1956 in Châteauroux) worked on Geometry but is best known for Richard's paradox involving the set of real numbers which can be defined in a finite number of words.*SAU
Kurt Gödel considered his incompleteness theorem as analogous to Richard's paradox which, in the original version runs as follows:
Let E be the set of real numbers that can be defined by a finite number of words. This set is denumerable. Let p be the nth decimal of the nth number of the set E; we form a number N having zero for the integral part and p + 1 for the nth decimal, if p is not equal either to 8 or 9, and unity in the contrary case. This number N does not belong to the set E because it differs from any number of this set, namely from the nth number by the nth digit. But N has been defined by a finite number of words. It should therefore belong to the set E. That is a contradiction.
Richard never presented his paradox in another form, but meanwhile there exist several different versions, some of which being only very loosely connected to the original. For the sake of completeness they may be stated here.

1982 Edward Hubert Linfoot (8 June 1905, 14 Oct 1982)was a British mathematician, primarily known for his work on optics, but also noted for his work in pure mathematics. Linfoot's mathematical papers cover the period 1926–1939, all his subsequent work being on optics. These papers cover a wide range of areas in Fourier analysis, number theory, and probability, the first of these being applied later to his optical studies. His optics work was primarily concerned with synthesis, error balancing, assessment and testing. In particular he used his prodigious mathematical background to determine ways to improve and invent new optical configurations. *Wik

1984 Sir Martin Ryle (27 Sep 1918, 14 Oct 1984) British radio astronomer who developed revolutionary radio telescope systems and used them for accurate location of weak radio sources. With improved equipment, he observed the most distant known galaxies of the universe. Ryle and Antony Hewish shared the Nobel Prize for Physics in 1974, the first Nobel prize in the field of astronomy. Ryle helped develop radar for British defense during WW II. Afterward, he was a leader in the development of radio astronomy. Using interferometry he and his team located radio-emitting regions on the sun and pinpointed other radio sources so that they could be studied in visible light. Ryle’s catalogues of radio sources led to the discovery of numerous radio galaxies and quasars. He was Astronomer Royal 1972 to 1982.

1991 Walter M. Elsasser (20 Mar 1904, 14 Oct 1991) German-born American physicist notable for a variety of contributions to science. He is known for his explanation of the origin and properties of the Earth's magnetic field using a "dynamo model." Trained as a theoretical physicist, he made several important contributions to fundamental problems of atomic physics, including interpretation of the experiments on electron scattering by Davisson and Germer as an effect of de Broglie's electron waves and recognition of the shell structure of atomic nuclei. Circumstances later turned his interests to geophysics, where he had important insights about the radiative transfer of heat in the atmosphere and fathered the generally accepted dynamo theory of the earth's magnetism. *TIS

2010 Benoit Mandelbrot (20 November 1924 – 14 October 2010) was largely responsible for the present interest in Fractal Geometry. He showed how Fractals can occur in many different places in both Mathematics and elsewhere in Nature.*SAU He was a French American mathematician.
Mandelbrot worked on a wide range of mathematical problems, including mathematical physics and quantitative finance, but is best known as the father of fractal geometry. He coined the term fractal and described the Mandelbrot set. Mandelbrot also wrote books and gave lectures aimed at the general public.
Mandelbrot spent most of his career at IBM's Thomas J. Watson Research Center, and was appointed as an IBM Fellow. He later became a Sterling Professor of Mathematical Sciences at Yale University, where he was the oldest professor in Yale's history to receive tenure. Mandelbrot also held positions at the Pacific Northwest National Laboratory, Université Lille Nord de France, Institute for Advanced Study and Centre National de la Recherche Scientifique.
Mandelbrot died in a hospice in Cambridge, Massachusetts, on 14 October 2010 from pancreatic cancer, at the age of 85. Reacting to news of his death, mathematician Heinz-Otto Peitgen said "if we talk about impact inside mathematics, and applications in the sciences, he is one of the most important figures of the last 50 years." *Wik

2010 Wilhelm Paul Albert Klingenberg (28 January 1924 Rostock, Mecklenburg, Germany – 14 October 2010 Röttgen, Bonn) was a German mathematician who worked on differential geometry and in particular on closed geodesics. One of his major achievements is the proof of the sphere theorem in joint work with Marcel Berger in 1960: The sphere theorem states that a simply connected manifold with sectional curvature between 1 and 4 is homeomorphic to the sphere. *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

Friday, 13 October 2017

On This Day in Math - October 13

No matter how correct a mathematical theorem may appear to be, one ought never to be satisfied that there was not something imperfect about it until it also gives the impression of being beautiful.
~George Boole

The 286th day of the year; 286 is a tetrahedral number (a triangular pyramid, note that 285 was a square pyramidal number, how often can they occur in sequence?) It is the sum of the first eleven triangular numbers, 286 = 1 + 3 + 6 + 10 + 15 + 21 + 28 + 36 + 45 + 55 + 66

And to top yesterday's curiosity, here are four squares with the same digits 2862=81796, 1372=18769, 1332 = 17 689, 2812 =78961

EVENTS

2128 B.C. In China the earliest record of solar eclipse was made.*VFR (This date seems to have been computed back by a Buddhist astronomer,I-Hang in about 720 AD based on the year of the Dynasty for which it was recorded.)

1597 Kepler replied to Galileo’s letter of 4 August 1597 urging him to be bold and proceed openly in his advocacy of Copernicanism. [Eves, Circles, 159◦] *VFR

1729 Euler mentioned the gamma function in a letter to Goldbach. In 1826 Legendre gave the function its symbol and name. [Cajori, History of Mathematical Notations, vol. 2, p. 271] (the Oct 13 date is for the Julian Calendar still used in Russia when Euler wrote from there. It was the 24th in most of the rest of the world using the Gregorian Calendar.)
In this same letter, Euler gives the relation we would now write as $\frac{1}{2}! = \frac{\sqrt {\pi}}{2}$ and points out many other fractional relations. *Detlef Gronau Why the Gamma Function So As It Is

 Sketch of M51 by Lord Rosse in 1845, *Wik
1773 What later became known as the Whirlpool Galaxy was discovered on October 13, 1773 by Charles Messier while hunting for objects that could confuse comet hunters, and was designated in Messier's catalogue as M51. *David Dickinson ‏@Astroguyz

1860 The earliest surviving aerial photograph is titled 'Boston, as the Eagle and the Wild Goose See It.' Taken by James Wallace Black and Samuel Archer King on October 13, 1860, it depicts Boston from a height of 630m. Aerial photography was first practiced by the French photographer and balloonist Gaspard-Félix Tournachon, known as "Nadar", in 1858 over Paris, France. The photographs he produced no longer exist. *Smithsonian *Wik

1884 An international conference in Washington D. C. decided “to adopt the meridian passing through the center of the transit instrument at the Observatory of Greenwich as the initial meridian for longitude.” Greenwich Mean Time, or GMT, was born. If someone ever asked you what President Chester Arthur did for us (don't say "Who?") simply say he pushed for the International Meridian Conference in Washington.

Addendum: I have been gently corrected by Rebekah Higgitt ‏@beckyfh and Thony Christie ‏@rmathematicus that in fact "The resolutions from the conference were only proposals – it was up to the respective governments to show political will and implement them ..." and that happened slowly. I am also aware that GMT was widely used in the UK before this conference to standardize railway time tables. A good source on a little more detail is at the Greenwich Meridian Org

1893 The term "Diophantine equation" appears in English in 1893 in Eliakim Hastings Moore (1862-1932), "A Doubly-Infinite System of Simple Groups," Bulletin of the New York Mathematical Society, *Jef Miller, Earliest Known Uses of Some of the Words of Mathematics

1904 Clever Hans, The horse that could do math is investigated by Oskar Pfungst. The investigation will continue for six weeks.
Hans was a horse owned by Wilhelm von Osten, who was a gymnasium mathematics teacher, an amateur horse trainer, phrenologist, and something of a mystic. Hans was said to have been taught to add, subtract, multiply, divide, work with fractions, tell time, keep track of the calendar, differentiate musical tones, and read, spell, and understand German. Von Osten would ask Hans, "If the eighth day of the month comes on a Tuesday, what is the date of the following Friday?” Hans would answer by tapping his hoof. Questions could be asked both orally, and in written form. Von Osten exhibited Hans throughout Germany, and never charged admission. Hans's abilities were reported in The New York Times in 1904. After von Osten died in 1909, Hans was acquired by several owners. After 1916, there is no record of him and his fate remains unknown.
psychologist Oskar Pfungst demonstrated that the horse was not actually performing these mental tasks, but was watching the reaction of his human observers.*Wik

1915 "Precision Computer" - The issue of the Engineering and Contracting journal for this date, in addition to details of a new three-ton worm drive contractors truck, advised of the availability of the new Ross Precision Computer. This circular slide rule consists of a silver-colored metal dial, 8-1/2" wide, mounted on a silver-colored metal disc. Three oblong holes on the base disc permit the reading of trigonometric scales on a white celluloid and cardboard disc that is between the metal discs. (HT to JF Ptak ‏@ptak)

In 1985, at the Fermi National Accelerator Laboratory in Illinois, the first observation was made of proton-antiproton collisions by the Collider Detector at Fermilab (CDF) with 1.6 TeV center-of-mass energy. In all, 23 of collisions were detected in Oct 1985. The Tevatron, four miles in circumference (originally named the Energy Doubler), is the world's highest-energy particle accelerator. Its low-temperature cooling system was the largest ever built when it was placed in operation in 1983. Its 1,000 superconducting magnets are cooled by liquid helium to -268 deg C (-450 deg F). Fermilab (originally named the National Accelerator Laboratory) was commissioned by the U.S. Atomic Energy Commission, in a bill signed by President Johnson on 21 Nov 1967.  *TIS

BIRTHS

1734 William Small (13 October 1734; Carmyllie, Angus, Scotland – 25 February 1775; Birmingham, England). He attended Dundee Grammar School, and Marischal College, Aberdeen where he received an MA in 1755. In 1758, he was appointed Professor of Natural Philosophy at the College of William and Mary in Virginia, then one of Britain’s American colonies.
Small is known for being Thomas Jefferson's professor at William and Mary, and for having an influence on the young Jefferson. Small introduced him to members of Virginia society who were to have an important role in Jefferson's life, including George Wythe a leading jurist in the colonies and Francis Fauquier, the Governor of Virginia.
Recalling his years as a student, Thomas Jefferson described Small as:
"a man profound in most of the useful branches of science, with a happy talent of communication, correct and gentlemanly manners, and a large and liberal mind... from his conversation I got my first views of the expansion of science and of the system of things in which we are placed."
In 1764 Small returned to Britain, with a letter of introduction to Matthew Boulton from Benjamin Franklin. Through this connection Small was elected to the Lunar Society, a prestigious club of scientists and industrialists.
In 1765 he received his MD and established a medical practice in Birmingham, and shared a house with John Ash, a leading physician in the city. Small was Boulton's doctor and became a close friend of Erasmus Darwin, Thomas Day, James Keir, James Watt, Anna Seward and others connected with the Lunar Society. He was one of the best-liked members of the society and an active contributor to their debates.
Small died in Birmingham on 25 February 1775 from malaria contracted during his stay in Virginia. He is buried in St. Philips Church Yard, Birmingham.
The William Small Physical Laboratory, which houses the Physics department at the College of William & Mary, is named in his honor. *Wik

1776 Peter Barlow (13 Oct 1776; 1 Mar 1862) English mathematician and engineer who invented two varieties of achromatic (non-colour-distorting) telescope lenses. In 1819, Barlow began work on the problem of deviation in ship compasses caused by the presence of iron in the hull. For his method of correcting the deviation by juxtaposing the compass with a suitably shaped piece of iron, he was awarded the Copley Medal. In 1822, he built a device which is to be considered one of the first models of an electric motor supplied by continuous current. He also worked on the design of bridges, in particular working (1819-26) with Thomas Telford on the design of the bridge over the Menai Strait, the first major modern suspension bridge. Barlow was active during the period of railway building in Britain.*TIS

1885 Viggo Brun (13 October 1885, Lier – 15 August 1978, Drøbak) was a Norwegian mathematician.
He studied at the University of Oslo and began research at the University of Göttingen in 1910. In 1923, Brun became a professor at the Technical University in Trondheim and in 1946 a professor at the University of Oslo. He retired in 1955 at the age of 70.
In 1915, he introduced a new method, based on Legendre's version of the sieve of Eratosthenes, now known as the Brun sieve, which addresses additive problems such as Goldbach's conjecture and the twin prime conjecture. He used it to prove that there exist infinitely many integers n such that n and n+2 have at most nine prime factors (9-almost primes); and that all large even integers are the sum of two 9 (or smaller)-almost primes.
In 1919 Brun proved that the sum of the reciprocals of the twin primes converges to Brun’s constant:
1⁄3  +  1 ⁄5  +  1⁄ 5 + 1⁄7 + 1 ⁄11 + 1⁄ 13 + 1⁄17 + 1 ⁄19 + . . . = 1.9021605 . . .by contrast, the sum of the reciprocals of all primes is divergent. He developed a multi-dimensional continued fraction algorithm in 1919/20 and applied this to problems in musical theory.
He also served as praeses of the Royal Norwegian Society of Sciences and Letters in 1946.
It was in 1994, while he was trying to calculate Brun’s constant,
that Thomas R. Nicely discovered a famous flaw in the Intel Pentium
microprocessor. The Pentium chip occasionally gave wrong answers
to a floating-point (decimal) division calculations due to errors in five
entries in a lookup table on the chip. Intel spent millions of dollars
replacing the faulty chips.
More recently, Nicely has calculated that the value of Brun’s constant
1s 1.902160582582 _ 0.000000001620.
*Wik

1890 Georg Feigel born in Homburg, Germany. At the University of Berlin he developed an intro¬ductory course, Einf¨uhrung in die H¨ohere Mathematik (published, posthumeously, 1953) which was responsible for introducing the new fundamental concepts of mathematics based on axioms and structures into the universities. *VFR

1893 Kurt Werner Friedrich Reidemeister (13 Oct 1893, 8 July 1971) Reidemeister was a pioneer of knot theory and his work had a great influence on Group Theory. Reidemeister's other interests included the philosophy and the foundations of mathematics. He also wrote about poets and was a poet himself. He translated Mallarmé. *SAU

1915  Arthur Burks​, a principal designer of the ENIAC, was born. Burks -- who was born in Duluth, Minn., and educated at DePauw University and the University of Michigan -- did extensive work on the ENIAC, the machine designed at the University of Pennsylvania​’s Moore School and completed in 1946. After working with J. Presper Eckert​ and John Mauchly on the ENIAC, Burks moved on to Princeton University, where he helped John von Neumann develop his computer at the Institute for Advanced Studies.*CHM

1932 John Griggs Thompson (13 Oct 1932, )American mathematician who was awarded the Fields Medal in 1970 for his work in group theory, solving (with Walter Feit) one of its thorniest problems, the so-called "odd order" problem. (Group theory is a branch of mathematics that focuses on the study of symmetries - such as the symmetries of a geometric figure, or symmetries that arise in solutions to algebraic equations.) Thompson's proof, with 253 pages of equations, filled an entire issue of the Pacific Journal of Mathematics. It stands out as one of math’s longest and most complex. Thompson also collaborated on the classification of the finite simple groups, the building blocks of more general groups. Group theory has important applications in physics, chemistry and other fields.*TIS

DEATHS

1715 Nicolas Malebranche was a major French philosopher and follower of Descartes whose ideas he developed to bring them more in line with standard Roman Catholic orthodox belief.*SAU

1793 William Hopkins FRS (2 February 1793 – 13 October 1866) was an English mathematician and geologist. He is famous as a private tutor of aspiring undergraduate Cambridge mathematicians, earning him the sobriquet the senior-wrangler maker.
Before graduation, Hopkins had married Caroline Frances Boys (1799–1881) and was, therefore, ineligible for a fellowship. He instead maintained himself as a private tutor, coaching the young mathematicians who sought the prestigious distinction of Senior Wrangler. He was enormously successful in the role, earning the sobriquet senior wrangler maker and grossing £700-800 annually. By 1849, he had coached almost 200 wranglers, of whom 17 were senior wranglers including Arthur Cayley and G. G. Stokes. Among his more famous pupils were Lord Kelvin, James Clerk Maxwell and Isaac Todhunter.
He also made important contributions in asserting a solid, rather than fluid, interior for the Earth and explaining many geological phenomena in terms of his model. However, though his conclusions proved to be correct, his mathematical and physical reasoning were subsequently seen as unsound.In 1833, Hopkins published Elements of Trigonometry and became distinguished for his mathematical knowledge.
There was a famous story that the theory of George Green (1793–1841) was almost forgotten. In 1845, Lord Kelvin (William Thomson, a young man in 1845) got some copies of Green's 1828 short book from William Hopkins. Subsequently, Lord Kelvin helped to make Green's 1828 work famous according to the book "George Green" written by D.M. Cannell. *Wik

1913 Gyula Vályi (5 January 1855 - 13 October 1913) was a Hungarian mathematician and theoretical physicist, a member of the Hungarian Academy of Sciences, known for his work on mathematical analysis, geometry, and number theory.*Wik

1987 Walter H. Brattain (10 Feb 1902, 13 Oct 1987) Walter Houser Brattain was an American scientist born in China who, with John Bardeen and William B. Shockley, won the Nobel Prize for Physics in 1956 for investigating semiconductors (materials of which transistors are made) and for the development of the transistor. At college, he said, he majored in physics and math because they were the only subjects he was good at. He became a solid physicist with a good understanding of theory, but his strength was in physically constructing experiments. Working with the ideas of  Shockley and Bardeen, Brattain's hands built the first transistor. Shortly, the transistor replaced the bulkier vacuum tube for many uses and was the forerunner of microminiature electronic parts.*TIS

1990 Hans Freudenthal, . *VFR   (September 17, 1905, Luckenwalde, Brandenburg – October 13, 1990) was a Dutch mathematician. He was Professor Emeritus at Utrecht University when he died at age 85. He made substantial contributions to algebraic topology and also took an interest in literature, philosophy, history and mathematics education. *Wik

2001 Olga Arsenevna Oleinik (2 July 1925, 13 Oct 2001) Oleinik wrote over 370 published papers and eight books. Her main research was concerned with algebraic geometry, partial differential equations, and mathematical physics. Winner of numerous prizes including the 1952 Chebotarev Prize for her research on elliptic equations with a small parameter in the highest derivative, the 1964 Lomonosov Prize for research on asymptotic properties of the solutions of problems of mathematical physics, and the 1988 State Prize for her series of papers on the investigation of boundary-value problems for differential operators and theirs applications in mathematical physics. In 1985 she was awarded the honorary title of Honored Scientist of the Russian Federation for her achievements in research and teaching, and in 1995 was awarded the Order of Honor by the president of the Russian Federation. She was also the 1996 AWM Noether Lecturer.*Agnes Scott College,

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, 12 October 2017

On This Day in Math - October 12

"Yet I exist in the hope that these memoirs ...
may find their way to the minds of humanity in Some Dimensions,
and may stir up a race of rebels who shall refuse to be confined to limited Dimensionality."
~ Edwin Abbott Abbott, Flatland

The 285th day of the year, 285 is a square pyramidal number (like a stack of cannonballs, or oranges with the base in a square)... Or.. the sum of the first nine squares. $285 = \sum _{i=1} ^ 9 (i^2)$

285 is 555 in base 7.

Not sure how rare this is, but just saw it on MAA's Number a Day and was intrigued, 285^2 = 81225 uses the same digits as 135^2 (18225) and 159^2 (25281).

EVENTS

1793 At the University of North Carolina, the cornerstone was laid for “Old East,” the oldest state university building in the U.S.*VFR

1810 the German festival Oktoberfest was first held in Munich.  Reaaly good ideas WILL spread.

1850, classes began at the Women's Medical College of Pennsylvania, the first medical school entirely for women.*TIS

1884 George Bruce Halsted presented his inaugural address before the Texas Academy of Science. He spoke of his teacher at Johns Hopkins, J. J. Sylvester, and related how the rumor started that Sylvester killed a student when he was at the university of Virginia. [Science, 22 February 1885; vol. 1, no. 8, p. 265] *VFR

1988 Steve Jobs unveiled the NeXT, the computer he designed after moving on from Apple Computer Inc., which he had founded with Steve Wozniak. Although the NeXT ultimately failed, it introduced several features new to personal computers, including an optical storage disk, a built-in digital signal processor that allowed voice recognition, and object-oriented languages that simplified programming. On a microprocessor with 8 megabytes of RAM, however, the NeXT ran too slowly to be popular. NeXT Computer Inc. eventually became NeXT Software Inc. and then was bought by Apple in 1997.

1996: A solar eclipse was broadcast live on the internet for the first time. * BBC Archive @BBCArchive

BIRTHS

1827 Josiah Parsons Cooke (October 12, 1827 – September 3, 1894) was an American scientist who worked at Harvard University and was instrumental in the measurement of atomic weights, inspiring America's first Nobel laureate in chemistry, Theodore Richards, to pursue similar research. Cooke's 1854 paper on atomic weights has been said to foreshadow the periodic law developed later by Mendeleev and others. Historian I. Bernard Cohen described Cooke "as the first university chemist to do truly distinguished work in the field of chemistry" in the United States. *Wik

1860 Elmer Sperry (12 Oct 1860; 16 Jun 1930) American electrical engineer and inventor of the gyrocompass. In the 1890's he made useful inventions in electric mining machinery, and patent electric brake and control system for street- or tramcars. In 1908, he patented the active gyrostabilizer which acted to stop a ship's roll as soon as it started. He patented the first gyrocompass designed expressly for the marine environment in 1910. This "spinning wheel" gyro was a significant improvement over the traditional magnetic compass of the day and changed the course of naval history. The first Sperry gyrocompass was tested at-sea aboard the USS Delaware in 1911 and established Sperry as a world leader in the manufacture of military gyrocompasses for the next 80 years. *TIS

DEATHS

1492 Piero della Francesca (June 1420, 12 Oct 1492) was an Italian artist who pioneered the use of perspective in Renaissance art and went on to write several mathematical treatises. In his own time he was also known as a highly competent mathematician. In his Lives of the most famous painters ... [13], Giorgio Vasari (1511-1572) says that Piero showed mathematical ability in his earliest youth and went on to write 'many' mathematical treatises. Of these, three are now known to survive. The titles by which they are known are: Abacus treatise (Trattato d'abaco), Short book on the five regular solids (Libellus de quinque corporibus regularibus) and On perspective for painting (De prospectiva pingendi). Piero almost certainly wrote all three works in the vernacular (his native dialect was Tuscan), and all three are in the style associated with the tradition of 'practical mathematics', that is, they consist largely of series of worked examples, with rather little discursive text.
The Abacus treatise is similar to works used for instructional purposes in 'Abacus schools'. It deals with arithmetic, starting with the use of fractions, and works through series of standard problems, then it turns to algebra, and works through similarly standard problems, then it turns to geometry and works through rather more problems than is standard before (without warning) coming up with some entirely original three-dimensional problems involving two of the 'Archimedean polyhedra' (those now known as the truncated tetrahedron and the cuboctahedron).
Four more Archimedeans appear in the Short book on the five regular solids: the truncated cube, the truncated octahedron, the truncated icosahedron and the truncated dodecahedron. (All these modern names are due to Johannes Kepler (1619).) Piero appears to have been the independent re-discoverer of these six solids. Moreover, the way he describes their properties makes it clear that he has in fact invented the notion of truncation in its modern mathematical sense.
On perspective for painting is the first treatise to deal with the mathematics of perspective, a technique for giving an appearance of the third dimension in two-dimensional works such as paintings or sculptured reliefs. Piero is determined to show that this technique is firmly based on the science of vision (as it was understood in his time). He accordingly starts with a series of mathematical theorems, some taken from the optical work of Euclid (possibly through medieval sources) but some original to Piero himself. Some of these theorems are of independent mathematical interest, but on the whole the work is conceived as a manual for teaching painters to draw in perspective, and the detailed drawing instructions are mind-numbing in their repetitiousness. There are many diagrams and illustrations, but unfortunately none of the known manuscripts has illustrations actually drawn by Piero himself.
None of Piero's mathematical work was published under his own name in the Renaissance, but it seems to have circulated quite widely in manuscript and became influential through its incorporation into the works of others. Much of Piero's algebra appears in Pacioli's Summa (1494), much of his work on the Archimedeans appears in Pacioli's De divina proportione (1509), and the simpler parts of Piero's perspective treatise were incorporated into almost all subsequent treatises on perspective addressed to painters. *SAU

Picard also travelled to Tycho Brahe's Danish observatory, Uraniborg, in order to assess its position accurately so that Tycho's readings could be compared to others'. Picard collaborated and corresponded with many scientists, including Isaac Newton, Christiaan Huygens, Ole Rømer, Rasmus Bartholin, Johann Hudde​, and even his main competitor, Giovanni Cassini, although Cassini was often less than willing to return the gesture. These correspondences led to Picard's contributions to areas of science outside the field of geodesy, such as the aberration of light he observed while in Uraniborg, or his discovery of mercurial phosphorescence upon his observance of the faint glowing of a barometer. This discovery led to Newton's studies of spectrometry.
Picard also developed what became the standard method for measuring the right ascension of a celestial object. In this method, the observer records the time at which the object crosses the observer's meridian. Picard made his observations using the precision pendulum clock that Dutch physicist Christiaan Huygens had recently developed. His book "Mesure de la Terre" was published in 1671.*Wik

1912 Lewis Boss (26 Oct 1846, 12 Oct 1912) American astronomer best known for his compilation of two catalogues of stars (1910, 1937). In 1882 he led an expedition to Chile to observe a transit of Venus. About 1895 Boss began to plan a general catalog of stars, giving their positions and motions. After 1906, the project had support from the Carnegie Institution, Washington, D.C. With an enlarged staff he observed the northern stars from Albany and the southern stars from Argentina. With the new data, he corrected catalogs that had been compiled in the past, and in 1910 he published the Preliminary General Catalogue of 6,188 Stars for the Epoch 1900. The work unfinished upon his death was completed by his son Benjamin in 1937*TIS

1926 Edwin Abbott Abbott (20 Dec 1838, 12 Oct 1926) His most famous work was Flatland: a romance of many dimensions (1884) which Abbott wrote under the pseudonym of A Square. The book has seen many editions, the sixth edition of 1953 being reprinted by Princeton University Press in 1991 with an introduction by Thomas Banchoff​. Flatland is an account of the adventures of A Square in Lineland and Spaceland. In it Abbott tries to popularise the notion of multidimensional geometry but the book is also a clever satire on the social, moral, and religious values of the period.
More recently, in 2002, an annotated version of Flatland has been produced with an introduction and notes by Ian Stewart who gives extensive discussion of mathematical topics related to passages in Abbott's text. *SAU The Kindle edition of Flatland is available for less than $2.00 Flatland: A Romance of Many Dimensions [Illustrated] and the Stewart version is only a little more: In a bold statement of personal opinion I add: This book should be read by every teacher and every student of mathematics. 1936 William Sheppard read Mathematics at Cambridge and then went on to study Law. He was appointed to the Department of Education. His mathematical interests were mainly in Statistics. *SAU 1984 Georgii Dmitrievic Suvorov (19 May 1919, 12 Oct 1984) made major contributions to the theory of functions. He worked, in particular, on the theory of topological and metric mappings on 2-dimensional space. Another area on which Suvorov worked was the theory of conformal mappings and quasi-formal mappings. His results in this area, mostly from the late 1960s when he was at Donetsk, are of particular significance. He extended Lavrentev's results in this area, in particular Lavrentev's stability and differentiability theorems, to more general classes of transformations. One of the many innovations in Suvorov's work was new methods which he introduced to help in the understanding of metric properties of mappings with bounded Dirichlet integral. *SAU 2011 Dennis MacAlistair Ritchie (September 9, 1941; found dead October 12, 2011), was an American computer scientist who "helped shape the digital era." He created the C programming language and, with long-time colleague Ken Thompson, the UNIX operating system. Ritchie and Thompson received the Turing Award from the ACM in 1983, the Hamming Medal from the IEEE in 1990 and the National Medal of Technology from President Clinton in 1999. Ritchie was the head of Lucent Technologies System Software Research Department when he retired in 2007. He was the 'R' in K&R C and commonly known by his username dmr. *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 Wednesday, 11 October 2017 On This Day in Math - October 11 Jeannie at the tomb of Tristan (from Tristan and Isolde) near Fowey, Cornwall Perhaps some day in the dim future it will be possible to advance the computations faster than the weather advances and at a cost less than the saving to mankind due to the information gained. But that is a dream. — Lewis Fry Richardson The 284th day of the year; 284 is an amicable (or friendly) number paired with 220. The divisors of 220 add up to 284 and the divisors of 284 add up to 220. Amicable numbers were known to the Pythagoreans, who credited them with many mystical properties. A general formula by which some of these numbers could be derived was invented circa 850 by Thābit ibn Qurra (826-901).(Can you find the next pair?) jim wilder ‏@wilderlab pointed out a variation of friendly numbers in degree three... "Along the lines of friendly numbers... 136 = 2³ + 4³ + 4³ and 244 = 1³ + 3³ + 6³" EVENTS 1606 Kepler, having heard of Thomas Harriot’s work in natural philosophy from his friend John Erickson writes to ask Harriot’s view on colors, refraction, and causes of the rainbow. *Henry Stevens, Thomas Hariot, the mathematician, the philosopher, and the scholar Thony Christie sent a tweet reminding me that Harriot's response did not include his knowledge of the law of sines for refraction. The law of refraction is named after Snel, but he was not the first person to discover it. The first discoverer seems to have been Thomas Harriot, who knew it by 1602, based on his observations in 1597 and 1598, but died before he could publish it. Snel's re-discovery of the law came in 1621; but he did not publish it before his death in 1626. Descartes was the first person to publish it, in his famous “Discourse on Method” *rohan.sdsu.edu 1809 Gauss’s wife Johanne died, following the birth of her third child Louis. *VFR 1868 Thomas Alva Edison ﬁled papers for his ﬁrst invention, an electronic vote recorder to rapidly tabulate ﬂoor votes in Congress. Members of Congress rejected it. *VFR  The macaroni box (1885) *Wik 1887 Patent #371,496 issued for the “comptometer,” the ﬁrst adding machine “absolutely accurate at all times.” It was invented by Dorr Eugene Felt of Chicago; a model was constructed in 1884. It wasn’t ﬁrst. *VFR This patent for the adding machine was granted to Dorr Eugene Felt of Chicago, Illinois. His Comptometer was the first practical key-driven calculator with sufficient speed, reliability and economic benefit. He called his original prototype the "Macaroni box", a rough model that Felt created over the year-end holidays in 1884-85. The casing was a grocery macaroni box, assembled with a jackknife using meat skewers as keys, staples as key guides and elastic bands for springs. Door improved his design, producing his earliest commercial wooden-box Comptometer from 1887 thru 1903, leading to the first steel case Model A (1904 that would be standard for the remainder for all "shoebox" models. Electric motor drive was introduced in the 1920's. *TIS 1939 Albert Einstein “wrote” President F. D. Roosevelt that “Some recent work by E. Fermi and L. Szilard ... leads me to expect that the element uranium may be turned into a new and important source of energy in the immediate future. ... This new phenomenon would also lead to the construction of bombs, and it is conceivable—though much less certain—that extremely powerful bombs of a new type may be constructed.” The letter, drafted by Fermi, Szilard, and Wigner and seems not to have actually been signed by Einstein until August 10, and was then given to Alexander Sachs, a confident of Roosevelt, who did not deliver it to him until October 30. Roosevelt quickly started the Manhattan Project. Einstein later regretted signing this letter. *(VFR & Brody & Brody); (the letter can be read at Letters of Note) They recognized the process could generate a lot of energy leading to power and possibly weapons. There was also concern the Nazi government of Germany was already searching for an atomic weapon. This letter would accomplish little more than the creation of a "Uranium Committee" with a budget of$6,000 to buy uranium and graphite for experiments.
Sir Fred Soddy's book, The Interpretation of Radium, inspired H G Wells to write The World Set Free in 1914, and he dedicated the novel to Soddy's book. Twenty years later, Wells' book set Leo Szilard to thinking about the possibility of Chain reactions, and how they might be used to create a bomb, leading to his getting a British patent on the idea in 1936. A few years later Szilard encouraged his friend, Albert Einstein , to write a letter to President Roosevelt about the potential for an atomic bomb. The prize-winning science-fiction writer, Frederik Pohl , talks about Szilard's epiphany in Chasing Science (pg 25),
".. we know the exact spot where Leo Szilard got the idea that led to the atomic bomb. There isn't even a plaque to mark it, but it happened in 1938, while he was waiting for a traffic light to change on London's Southampton Row. Szilard had been remembering H. G. Well's old science-fiction novel about atomic power, The World Set Free and had been reading about the nuclear-fission experiment of Otto Hahn and Lise Meitner, and the lightbulb went on over his head."

1988 A 109 digit number, 11104 +1, was factored by Mark Manasse and Arjen Lenstra using a quadratic sieve and a network of hundreds of computers in the US, Europe, and Australia. *FFF pg 570
For those who care to attempt to find the factors for themselves, here are the digits:
as provided by Wolfram Alpha

BIRTHS

1675 Samuel Clarke (11 October 1675 Norwich – 17 May 1729), defender of Newton’s physical theories against Leibniz. *VFR Clarke was considered the greatest metaphysician in England when Locke died in 1704. In 1706 Newton asked Clarke to translate his Opticks into Latin.*SAU

1758 (Heinrich) Wilhelm (Matthäus) Olbers(11 Oct 1758; 2 Mar 1840) was a German astronomer and physician, born in Arbergen, Germany. While practicing medicine at Bremen, he calculated the orbit of the comet of 1779, discovered the minor planets (asteroids) Pallas (1802) and Vesta (1807), and discovered five comets (all but one already observed at Paris). He also invented a method for calculating the velocity of falling stars. He is also known for Olber's paradox which asks "why is the night sky dark if there are so many bright stars all around to light it?" *TIS

1822 John Daniel Runkle (October 11, 1822 – July 8, 1902) was a U.S. educator and mathematician. B.S. in mathematics, 1851, Harvard College, second president of the Massachusetts Institute of Technology, was associated with the Nautical Almanac computation project from 1849 to 1884. In 1858 he founded the journal Mathematical Monthly and edited it for three years, when publication ceased. In 1860 he was a member of the committee that prepared the “Objects and Plan of an Institute of Technology” which led to the establishment of MIT. In 1862 he became MIT’s first secretary, and in 1865 he joined the new faculty as professor of mathematics, where he remained until 1902. He served as president pro-tem, 1868-1870, and was MIT’s second president, 1870-1878. He was married to Catherine Robbins Bird Runkle. *MIT History

1881 Lewis Fry Richardson (11 Oct 1881; 30 Sep 1953) British physicist and psychologist who first applied mathematics to accurate weather prediction. Richardson applied the mathematical method of finite differences to predicting the weather (1922). In his life, he held various posts: at the National Physical Laboratory, the Meteorological Office, and several university posts in physics or technology. Also, he was a chemist with National Peat Industries and in charge of the physical and chemical laboratory of the Sunbeam Lamp Co. Early application of mathematical techniques for systematically forecasting the weather were limited by extensive computation time: three months to predict weather for the next 24 hours. With electronic computers available after WW II made his methods became practical. He wrote several books applying mathematics to the causes of war. He contributed to calculus and the theory of diffusion for eddy-diffusion in the atmosphere. The Richardson number, a quantity involving gradients (change over distance) of temperature and wind velocity, is named after him.*TIS

1885 Alfréd Haar (11 October 1885, Budapest – 16 March 1933, Szeged) was a Hungarian mathematician who is best remembered for his work on analysis on groups, introducing a measure on groups, now called the Haar measure. *SAU
In 1904 he began to study at the University of Göttingen. His doctorate was supervised by David Hilbert. The Haar measure, Haar wavelet, and Haar transform are named in his honor. Between 1912 and 1919 he taught at Franz Joseph University in Kolozsvár. Together with Frigyes Riesz, he made the University of Szeged a centre of mathematics. He also founded the Acta Scientiarum Mathematicarum magazine together with Riesz. *Wik

1910 Cahit Arf (11 Oct 1910, 26 Dec 1997) Much of Arf's most important work was in algebraic number theory and he invented Arf invariants which have many applications in topology. His early work was on quadratic forms in fields, particularly fields of characteristic 2. His name is not only attached to Arf invariants but he is also remembered for the Hasse-Arf Theorem which plays an important role in class field theory and in Artin's theory of L-functions. In ring theory, Arf rings are named after him. *SAU

1916 Robert Eugene Marshak (October 11, 1916 – December 23, 1992) was an American physicist dedicated to learning, research, and education.
Marshak was born in the Bronx, New York City. His parents were immigrants to New York from Minsk. He was educated at Columbia University.
Marshak received his PhD from Cornell University in 1939. Along with his thesis advisor, Hans Bethe, he discovered many of the fusion aspects involved in star formation. This helped him on his work for the Manhattan Project, in Los Alamos, during World War II.
In 1947, at the Shelter Island Conference, Marshak presented his two-meson hypothesis about the pi-meson, which were discovered shortly thereafter.[1]
In 1957, he and George Sudarshan proposed a V-A ("vector" minus "axial vector") Lagrangian for weak interactions, which was later independently discovered by Richard Feynman and Murray Gell-Mann. His biography below, is explicit about it "Perhaps Marshak's most significant scientific contribution was the proposal of the V-A Theory of Weak Interactions (the fourth force in nature) in collaboration with his student George Sudarshan. Unfortunately, the pair published the theory only in a conference proceedings for a meeting in Italy. Six months later, a different derivation of the same concept was published by Feynman and Gell-Mann in a mainstream scientific journal. Marshak had talked with Feynman about the general problem in California some time before. Though the V-A Concept was considered to be one of the most important contributions to theoretical physics, a Nobel Prize was never awarded for it." Sudarshan himself later commented in a TV interview in 2006 that Murray Gell-Mann got the idea from him, in an informal coffee time!
He was Chairman of the Department of Physics at the University of Rochester for fourteen years (1956 to 1970)
He was the President of the City College of New York from 1970-1979.
Marshak died by accidental drowning in Cancún, Mexico in 1992. *Wik

DEATHS

1697 Stephano Angeli ( 23 September 1623 , Venice -  11 October 1697 , Padua)was an Italian mathematician who worked on infinitesimals and used them to study spirals, parabolas and hyperbolas.
In Bologna he came under the influence of Cavalieri.  Cavalieri was teaching at the University of Bologna, one of the oldest and most famous universities in Europe, dating from the 11th century. After leaving Bologna, Angeli continued his contacts with Cavalieri by correspondence, and was entrusted to publish Cavalieri's final work, Exercitationes geometricae sex, since by 1647 Cavalieri's health had deteriorated to such an extent that he was unable to carry out the work himself. Angeli also corresponded with a number of other mathematicians including Torricelli and Viviani.*SAU

1698 William Molyneux  (17 April 1656; Dublin – 11 October 1698; Dublin) was an Irish scientist and philosopher who worked on optics. Perhaps his best known scientific work was Dioptrica Nova, A treatise of dioptricks in two parts, wherein the various effects and appearances of spherick glasses, both convex and concave, single and combined, in telescopes and microscopes, together with their usefulness in many concerns of humane life, are explained, published in London 1692.
In 1687 he invented a new type of sundial called a Sciothericum telescopicum that used special double gnomon and a telescope to measure the time of noon to within 15 seconds. "measured time by day and night." *SAU

1708 Ehrenfried Walter von Tschirnhaus  (10 April 1651 – 11 October 1708) was a German mathematician who worked on the solution of equations and the study of curves. He is best known for the transformation which removes the term of degree n-1 from an equation of degree n. *SAU The Tschirnhaus transformation, by which he removed certain intermediate terms from a given algebraic equation, is well-known. It was published in the scientific journal Acta Eruditorum in 1683. In 1696, Johann Bernoulli posed the problem of the brachystochrone to the readers of Acta Eruditorum. Tschirnhaus was one of only five mathematicians to submit a solution. Bernoulli published these contributions (including Tschirnhaus') along with his own in the journal in May of the following year.
Von Tschirnhaus produced various types of lenses and mirrors, some of them are displayed in museums. He erected a large glass works in Saxony, where he constructed burning glasses of unusual perfection and carried on his experiments. *Wik

1731 John Craig (1663 – October 11, 1731) Scottish mathematician who published three important textbooks.While he was still a student in Edinburgh, Craig published Methodus figurarum lineis rectis et curvis comprehensarum quadraturas determinandi which contains Leibniz's dy/dx notation. This notation is also used in the work he published in 1693, Tractatus mathematicus de figurarum curvilinearum quadraturis et locis geometricis which was the first text published in England to contain the integration symbol ∫ . Dale writes "The standard of his work was such that he was noted as a mathematician of the first order ... and the "Acta Eruditorum" of Leipzig ranked him among the originators of the calculus (after Leibniz, but before Newton)". *SAU

1791 Johann Castillon (15 January 1704 in Castiglion Fiorentino, Toskana - 11. October 1791 in Berlin) was an Italian mathematician and astronomer who wrote on the cardioid and may have created the name.*SAU Castillon published the correspondence between Gottfried Wilhelm Leibniz and Johann Bernoulli , edited works of Leonhard Euler and published a review of Newton's Arithmetica Universalis. He also translated Locke's basic concepts of physics into French. *Wik

1852 Ferdinand Gotthold Max Eisenstein (16 Apr 1823, 11 Oct 1852) died of pulmonary tuberculosis at age 29.*VFR German mathematician whose work covered a range of topics including the theory of elliptic functions, and quadratic and cubic forms, which led to cyclotomy, the reciprocity theorem for cubic residues, and also theorems for quadratic and biquadratic residues from partition of prime numbers. *TIS In 1843 he met William Rowan Hamilton in Dublin, who gave him a copy of his book on Niels Henrik Abel's proof of the impossibility of solving fifth degree polynomials, a work that would stimulate Eisenstein's interest in mathematical research. He specialized in number theory and analysis, and proved several results that eluded even Gauss. *Wik

1889 James Prescott Joule (24 Dec 1818, 11 Oct 1889) English physicist who established that the various forms of energy - mechanical, electrical, and heat - are basically the same and can be changed, one into another. Thus he formed the basis of the law of conservation of energy, the first law of thermodynamics. He discovered (1840) the relationship between electric current, resistance, and the amount of heat produced. In 1849 he devised the kinetic theory of gases, and a year later announced the mechanical equivalent of heat. Later, with William Thomson (Lord Kelvin), he discovered the Joule-Thomson effect. The SI unit of energy or work , the joule (symbol J), is named after him. It is defined as the work done when a force of 1 newton moves a distance of 1 metre in the direction of the force.*TIS

1940 Vito Volterra (3 May 1860, 11 Oct 1940)Italian mathematician who made important contributions to calculus, and mathematical theories in astronomy, elasticity and biometrics. His mathematical talent appeared as a young boy. In 1905, he began to develop the theory of dislocations in crystals that led to improved understanding of the behaviour of ductile materials. During WWI he established the Italian Office of War Inventions and designed weapons for use by airships, for which he proposed the use of helium instead of flammable hydrogen. He is remembered for achievements in function theory and differential equations. In biology, in 1925, he formulated a pair of differential equations relating populations of prey and predators (also independently proposed by Alfred J. Lotka in 1925)*TIS (His date of death is sometimes given as 10 October, so that date is also listed)

1943 Geoffrey Thomas Bennett (30 June 1868, 11 Oct 1943) His most famous paper is the two page paper A new four-piece skew mechanism which he published in the journal Engineering in 1903. In it Bennett considers a skew hinged four-bar mechanism in three dimensional space. The angle between the hinges in a bar is called the twist. This mechanism is movable only if the opposite sides are equal. Then it follows as a consequence that the sines of the twists are proportional to the lengths of the bars. This remarkable mechanism Bennett called a skew isogram. It uses the fewest rods possible to build a useful mechanism. In a subsequent 22 page paper The skew isogram mechanism which he published in 1914, Bennett presented many interesting properties of the skew isogram, some without proofs. These proofs were not written down until Bernard Groeneveld's thesis Geometrical considerations on space kinematics in connection with Bennett's mechanism presented to the Technische Hogeschool te Delft in 1954. In 1922 Bennett published The three-bar sextic curve. In this paper he obtained the characteristics of the curve (now called the couple curve) as the locus of the Laguerre images of the conjugate points on the Hessian of an elliptic cubic. He therefore treated a curve defined in the area of kinematics by the methods of algebraic geometry. *SAU A 1913 Paper on The skew Isogram by Bennett

1979 Franciszek Leja (January 27, 1885 in Grodzisko Górne near Przeworsk – October 11, 1979 in Kraków, Poland) Polish mathematician who greatly influenced Polish Mathematics in the period between the two World Wars.
He was born to a poor peasant family in the southeastern Poland. After graduating from the University of Lwów he was a teacher of mathematics and physics in high schools from 1910 until 1923, among others in Kraków. From 1924 until 1926 he was a professor at the Warsaw University of Technology and from 1936 until 1960 in the Jagiellonian University.
During the Second World War he lectured on the underground universities in Łańcut and Lezajsk. But after the German invasion of Poland in 1939 life there became extremely difficult. There was a strategy by the Germans to wipe out the intellectual life of Poland. To achieve this Germans sent many academics to concentration camps and murdered others. In one of such actions he was sent to the Sachsenhausen concentration camp which he fortunately survived.
Since 1948 he worked for the Institute of Mathematics of the Polish Academy of Sciences. He was a co-founder of the Polish Mathematics Society in 1919 and from 1963 until 1965 the chairman. Since 1931 he was a member of the Warsaw Science Society (TNW).
His main scientific interests concentrated on analytic functions, in particular the method of extremal points and transfinite diameters. *Wik

1989 Mark Grigorievich Krein (3 April 1907 – 17 October 1989) was a Soviet Jewish mathematician, one of the major figures of the Soviet school of functional analysis. He is known for works in operator theory (in close connection with concrete problems coming from mathematical physics), the problem of moments, classical analysis and representation theory.
He was born in Kiev, leaving home at age 17 to go to Odessa. He had a difficult academic career, not completing his first degree and constantly being troubled by anti-Semitic discrimination. His supervisor was Nikolai Chebotaryov.
He was awarded the Wolf Prize in Mathematics in 1982 (jointly with Hassler Whitney), but was not allowed to attend the ceremony.
He died in Odessa.
On 14 January 2008, the memorial plaque of Mark Krein was unveiled on the main administration building of I.I. Mechnikov Odessa National University. *Wik

1996 Lars Valerian Ahlfors (18 Apr 1907, 11 Oct 1996) Finnish mathematician who was awarded one of the first two Fields Medals in 1936 for his work with Riemann surfaces. He also won the Wolf Prize in 1981.*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