Saturday, 19 August 2017

On This Day in Math - August 19

Let us weigh the gain and the loss in wagering that God is. Let us consider the two possibilities. If you gain, you gain all; if you lose, you lose nothing. Hesitate not, then, to wager that He is.

Blaise Pascal,Pensees (1670)

The 231st day of the year; there are 231 cubic inches in a US Gallon, (admit it, you did NOT know that.) Ok, and it's also the sum of the squares of four distinct primes, 231 = 22 + 32 + 72 + 132.

$(3!)^3 + (2!)^4 - (1!)^5$

231 = 12 + 23 + 34 + 45 + 56 + 61 (loop 1-2-3-4-5-6-1)

231 = 98 + 76 + 54 + 3

*Derek Orr

EVENTS
1577 " On August 19, his new book is put to printing (one hundred copies) at John Day's press in Aldersgate. " The printing of John Dee's 'General and rare memorials...' begins.
ht  ‏@RCPmuseum

1758 Etienne Montucla received the approval from the censors for his Histoire des mathematiques. Often called the first true history of mathematics. *VFR

1791 "On this day in 1791, Benjamin Banneker (free African American scientist & almanac author) published his 1st Almanac."
*Bibliophilia ‏@Libroantiguo

1819 the first bicycle in the U.S. were seen in New York City. Such bicycle velocipedes or "swift walkers" had been imported that same year. Shortly thereafter, on 19 Aug 1819, the city's Common Council passed a law to "prevent the use of velocipedes in the public places and on the sidewalks of the city of New York."*TIS (Skateborders take note, you are not the first to be banned from the sidewalks)

In 1887, Dmitri Ivanovich Mendeleev (1834-1907) used a balloon to ascend above the cloud cover to an altitude of 11,500 feet (3.5 km) to observe an eclipse in Russia. He made the solo ascent above Klin without any prior experience. While his family was rather concerned, he paid no attention to controlling the balloon until after he had completed his observations, at which time he worked out how to land it. Mendeleev is the Russian chemist known for the ordering of the Periodic Table of the Elements. Yet, he was interested in many fields of science. He studied problems associated with Russia's natural resources, such as coal, salt, metals, and the petroleum industry. In 1876, he visited the U.S. to observe the Pennsylvania oil fields. *TIS

1888 Irving Stringham, after a few years at the newly formed University of California at Berkeley, writes Felix Klein, his old professor, to complain that, "I impatiently await the time when it will be possible to bring some important researchers in the field of mathematics to the California coast." *Karen Hunger Parshall, David E. Rowe; The Emergence of the American Mathematical Research Community, 1876-1900

BIRTHS

1584 Pierre Vernier born (19 August 1580 at Ornans, Franche-Comté, Spanish Habsburgs (now France) – 14 September 1637 same location). He developed an accurate scale for the astrolabe. The Vernier scale that he invented in 1631 is still common on precision instruments. First described in English by John Barrow in 1750 in his Navigatio Britannica. It is sometimes called a nonius after Pedro Nunes, the Portuguese mathematician and instrument maker, who designed a precursor to the vernier scale in 1542. A nice illustration of how the Vernier alignment method works is at this Wikipedia site. *Wik
Clavius originated a way of dividing a scale for precise measurements. His idea was adopted by Vernier 42 years later.

1646 John Flamsteed (19 Aug 1646; 31 Dec 1719)English astronomer who established the Greenwich Observatory. Science Historian/blogger Thony Christie writes
"the observational astronomer John Flamsteed Observational astronomy only produced three significant star catalogues in the two thousand years leading up to the 18th century. The first, the Greek catalogue from Hipparchus and Ptolemaeus published by Ptolemaeus in the 2nd century CE, which contained just over 1000 stars mapped with an accuracy that was astounding for the conditions under which it was produced. The second, containing somewhat more that 700 stars plus another 300 borrowed from the Ptolemaeus catalogue, was produced by the Danish astronomer Tycho Brahe in the last quarter of the 16th century, with an accuracy many factors better than his Greek predecessors. Both of these catalogues were produced with naked eye observations. The first catalogue to be produced using telescopic sights on the measuring instruments was that of John Flamsteed published posthumously in 1725, which contains more than 3000 stars measured to a much higher degree of accuracy than that of Tycho."
He then goes on to correct some misconceptions about Flamsteed's life that are commonly repeated, (he did NOT take part in talking Charles II into creating the observatory) and gives a nice description of a complex man. *Renaissance Mathematicus

1739 Georg Simon Klügel (August 19, 1739 – August 4, 1812) made an exceptional contribution to trigonometry, unifying formulae and introducing the concept of trigonometric function, in his Analytische Trigonometrie. Euler, who studied similar problems 9 years later, in some respects achieved less than Klügel in this area. Folta writes:"Klügel's trigonometry was very modern for its time and was exceptional among the contemporary textbooks. "
It was his mathematical dictionary, however, which led to his fame. This was a three volume work which appeared between 1803 and 1808. In 1808 Klügel became seriously ill and could do no further work on the project. Another three volumes were added between 1823 and 1836 by Mollweide and Grunert and the dictionary was widely used for several generations making Klügel's name widely known. *SAU

1790 Edward John Dent (19 Aug 1790 - 8 Mar 1853).English clockmaker and inventor whose chronometers were noted for high accuracy. His patents in this field included compasses for navigation and surveying. He experimented with springs made of steel, gold and glass, and devices for counteracting the effects of temperature change upon timepiece mechanisms. As clockmaker to Queen Victoria, he was commissioned to build the Great Clock for the clock tower of the Houses of Parliament (known as Big Ben, although that is actually the nickname of its hour bell) which he began in the year he died. His son, Frederick Dent, completed the work the following year and it was installed in the tower in 1859. It continues to be recognised for its great accuracy of 4 seconds in a year.*TIS

1830 (Julius) Lothar Meyer (19 Aug 1830; 12 Apr 1895) was a German chemist who discovered the Periodic Law, independently of Dmitry Mendeleyev, at about the same time (1869). However, he did not develop the periodic classification of the chemical elements as thoroughly as Mendeleyev. Meyer trained originally in medicine and chemistry. He examined the effect of carbon monoxide on blood. In 1879, Meyer compared atomic volume to atomic weight. Plotted on a graph, the curve showed the periodicity of the elements. He also established the concept of valency by indicating that a given element combined with a characteristic number of hydrogen atoms, and coined the terms like univalent, bivalent, and trivalent, based on that number.*TIS

1872 Théophile Ernest de Donder (19 August 1872 – 11 May 1957) was a Belgian mathematician and physicist famous for his 1923 work in developing correlations between the Newtonian concept of chemical affinity and the Gibbsian concept of free energy.
He received his doctorate in physics and mathematics from the Université Libre de Bruxelles in 1899, for a thesis entitled Sur la Théorie des Invariants Intégraux (On the Theory of Integral Invariants).
He was professor between 1911 and 1942, at the Université Libre de Bruxelles. Initially he continued the work of Henri Poincaré and Élie Cartan. As from 1914 he was influenced by the work of Albert Einstein and was an enthusiastic proponent of the theory of relativity. He gained significant reputation in 1923, when he developed his definition of chemical affinity. He pointed out a connection between the chemical affinity and the Gibbs free energy.
He is considered the father of thermodynamics of irreversible processes. De Donder’s work was later developed further by Ilya Prigogine. De Donder was an associate and friend of Albert Einstein. *Wik

1934 Gordon Bell (August 19, 1934 - ) is born Digital Equipment Corporation​ (DEC) innovator . In his 23 years at DEC, Bell developed several of the company's most successful minicomputers as well as its well-known VAX machine. One the world's top computer architects, Bell is considered by many to be the father of the minicomputer and is also an authority on supercomputing. The author of several books, Bell's awards include the National Medal of Technology and the IEEE Von Neumann Medal. *CHM

1939 Alan Baker born in London (19 August 1939 - ). In 1970 he received a Fields Medal for his work on Hilbert’s seventh problem which dealt with transcendental numbers. *VFR In mathematics, a transcendental number is a number (possibly a complex number) that is not algebraic—that is, it is not a root of a non-constant polynomial equation with rational coefficients. The most prominent examples of transcendental numbers are π and e. The word transcendental seems to have been created by Liebniz. In 1900, David Hilbert posed an influential question about transcendental numbers, Hilbert's seventh problem: If a is an algebraic number, that is not zero or one, and b is an irrational algebraic number, is ab necessarily transcendental? The affirmative answer was provided in 1934 by the Gelfond–Schneider theorem. This work was extended by Alan Baker in the 1960s in his work on lower bounds for linear forms in any number of logarithms (of algebraic numbers). *Wik

1973 Olga Holtz (August 19, 1973 - ) is a Russian mathematician specializing in numerical analysis. She received the Sofia Kovalevskaya Award in 2006 and the European Mathematical Society Prize (2008). Since 2008, she is a member of the Young Academy of Germany.

Holtz's early mathematical development was largely due to her parents, who were both programmers.

After winning a €1,000,000 Sofia Kovalevskaya Award in 2006, Holtz built her research group at the Technical University Berlin, [ where she became a Professor of applied mathematics while concurrently serving as an Associate, then Full Professor of Mathematics at University of California, Berkeley. Since then, Holtz has garnered additional honors. The European Mathematical Society awarded her its 2008 prize, and the European Research Council awarded her €880,000 Starting Grant in August 2010. In 2015 she was elected as a fellow of the American Mathematical Society "for contributions to numerical linear algebra, numerical analysis, approximation theory, theoretical computer science, and algebra".

Holtz, who considered a career in music before deciding on mathematics, performs with the Berlin Philharmonic Choir and practices ballroom dancing, (in her spare time????)*Wik

DEATHS

1662 Blaise Pascal died (19 June 1623 – 19 August 1662). I can not be brief about a life that contained so much in such a short time, so I mention his death. Sickly for most of his life (autopsies showed he had a deformed skull), he grew much worse in 1662. Pascal was also in a severe depression after his sister's death the year. On the night before his death he went into convulsions and received the sacraments. His last words were "May God never abandon me." He was thirty-nine years old at the time of his death. He is buried in the cemetery of Saint-Étienne, the little church where he worshiped regularly in the fifth district of Paris, near the Parthenon. There is a simple small marker near the front of the church. While frequently overlooked today, it was a prestigious church during Pascal's life. *Wik Among Pascal's lesser known inventions, it seems that he may have established the first commercial bus line in Paris.  The profits were all to go to the monastery in Port Royal.*Peter L. Bernstein, Against the Gods

1703 John Wallis (23 Nov 1616, 19 Aug 1703) British mathematician who introduced the infinity math symbol. Wallis was skilled in cryptography and decoded Royalist messages for the Parliamentarians during the Civil War. Subsequently, he was appointed to the Savilian Chair of geometry at Oxford in 1649, a position he held until his death more than 50 years later. Wallis was part of a group interested in natural and experimental science which became the Royal Society, so Wallis is a founder member of the Royal Society and one of its first Fellows. Wallis contributed substantially to the origins of calculus and was the most influential English mathematician before Newton. *TIS In addition to the infinity sign, and the use of it's reciprocal for infinitesimals, he also is credited with the idea of number line. He also probably originated the terms "mantissa" and "continued fraction". The commonly repeated idea that he refused to believe negative numbers were "less than zero" is dispelled by his use of the number line to show 5 - 8 = -3 in his "Treatise on Algebra", in 1685. *personal correspondence from Professor Phillip Beeley, Wallis Project, Oxford Univ.

1822 Jean Baptiste Joseph chevalier Delambre (19 September 1749, Amiens – 19 August 1822, Paris) was a French mathematician and astronomer. He was also director of the Paris Observatory, and author of well-known books on the history of astronomy from ancient times to the 18th century. Delambre was one of the first astronomers to derive astronomical equations from analytical formulas. His name is also one of the 72 names inscribed on the Eiffel tower. Delambre died in 1822 and was interred in the Père Lachaise Cemetery in Paris.

1887 Alvan Clark (8 Mar 1804, 19 Aug 1887)American astronomer whose family became the first significant manufacturers of astronomical instruments in the U.S. His company manufactured apparatus for most American observatories of the era, including Lick and Pulkovo, and others in Europe. In 1862, while testing a telescope, Clark discovered the companion star to Sirius, which had previously been predicted but until then never sighted. The 18½-in objective telescope he used was subsequently delivered to the Dearborn Observatory, Chicago. His sons, Alvan Graham Clark and George Bassett Clark, continued the business. The unexcelled 40-in refractor telescopes for the 40-in Yerkes observatory was made by Alvan Graham Clark*TIS

1910 Eugène Rouché (18 August 1832 at Sommières, Hérault, France - 19 August 1910 at Lunel, Hérault) died on the day following his seventy-eighth birthday. A French Geometer who edited Laguerre's "Collected Works". He also is known for Rouche's Theorem on Complex functions. *SAU

1957 Maurice Kraitchik (April 21, 1882, Minsk - August 19, 1957, Bruxelles) was a Belgian mathematician, author, and game designer. His main interests were the theory of numbers and recreational mathematics.
He is famous for having inspired the two envelopes problem in 1953, with the following puzzle in La mathématique des jeux:
Two people, equally rich, meet to compare the contents of their wallets. Each is ignorant of the contents of the two wallets. The game is as follows: whoever has the least money receives the contents of the wallet of the other (in the case where the amounts are equal, nothing happens). One of the two men can reason: "Suppose that I have the amount A in my wallet. That's the maximum that I could lose. If I win (probability 0.5), the amount that I'll have in my possession at the end of the game will be more than 2A. Therefore the game is favorable to me." The other man can reason in exactly the same way. In fact, by symmetry, the game is fair. Where is the mistake in the reasoning of each man?

Kraitchik wrote several books on number theory during 1922-1930 and after the war, and from 1931 to 1939 edited Sphinx, a periodical devoted to recreational mathematics.

During World War II, Kraïtchik emigrated to the United States, where he taught a course at the New School for Social Research in New York City on the general topic of "mathematical recreations." *Wik

1951 Michael H. Freedman (21 April 1951 in Los Angeles, California, ). In 1986 he received a Fields Medal for his proof of the four-dimensional Poincar´e conjecture. *VFR [The Poincaré conjecture, one of the famous problems of 20th-century mathematics, asserts that a simply connected closed 3-dimensional manifold is a 3-dimensional sphere. The higher dimensional Poincaré conjecture claims that any closed n-manifold which is homotopy equivalent to the n-sphere must be the n-sphere. When n = 3 this is equivalent to the Poincaré conjecture. Smale proved the higher dimensional Poincaré conjecture in 1961 for n at least 5. Freedman proved the conjecture for n = 4 in 1982 but the original conjecture remained open until settled by G Perelman who was offered the 2006 Fields medal for his proof. ] *Wik

1957 Carl-Gustaf Arvid Rossby (28 Dec 1898, 19 Aug 1957) Swedish-U.S. meteorologist who first explained the large-scale motions of the atmosphere in terms of fluid mechanics. His work contributed to developing meteorology as a science. Rossby first theorized about the existence of the jet stream in 1939, and that it governs the easterly movement of most weather. U.S. Army Air Corps pilots flying B-29 bombing missions across the Pacific Ocean during World War II proved the jet stream's existence. The pilots found that when they flew from east to west, they experienced slower arrival times and fuel shortage problems. When flying from west to east, however, they found the opposite to be true. Rossby created mathematical models (Rossby equations) for computerized weather prediction (1950).*TIS

1964 Hugo Gernsback (August 16, 1884 – August 19, 1967), born Hugo Gernsbacher, was a Luxembourgish-American inventor, writer, editor, and magazine publisher, best known for publications including the first science fiction magazine. His contributions to the genre as publisher were so significant that, along with the novelists H. G. Wells and Jules Verne, he is sometimes called "The Father of Science Fiction". In his honour, annual awards presented at the World Science Fiction Convention are named the "Hugos" *Wik

1968 George Gamow (4 Mar 1904,19 Aug 1968) Russian-born American nuclear physicist, cosmologist and writer who was one of the foremost advocates of the big-bang theory, which desribes the origin of the universe as a colossal explosion that took place billions of years ago. In 1954, he expanded his interests into biochemistry and his work on deoxyribonucleic acid (DNA) made a basic contribution to modern genetic theory. *TIS
Einstein is often quoted as saying that his use of a "cosmological constant" in his equations for the General Theory of Relativity was his "greatest blunder".  Recently (2013) I read that Mario Livio suspected that the quote had been made up by Gamow and first appears in a Scientific American article in 1956.  He quotes Gamow's history of "antics" and a quote from his wife that  ""In more than twenty years together, Geo has never been happier than when perpetuating a practical joke." *Rebecca J Rosen, The Atlantic

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, 18 August 2017

On This Day in Math - August 18

The total number of Dirichlet's publications is not large: jewels are not weighed on a grocery scale.
~Karl F. Gauss

The 230th day of the year; 230 is the smallest number such that it and the next number are both sphenic numbers, the product of three distinct primes (230 = 2*5*23 and 231 = 3*7*11). *Prime Curios (can there be three consecutive numbers that are the product of three (or n) distinct primes

Their are 230 possible crystal shapes that can tile space (this counts the chiral reflections as separate). This is the analogy of the better known 17 "wallpaper groups" which tile the plane. Interestingly, both were proved by the same man, Evgraf Fedorov, in 1891. He did the plane problem the hard way, he proved the case for space first, then worked backwards to the plane.

EVENTS

1709 Cotes writes to Newton in hopes of prompting the revision of the Principia which Newton had promised to deliver in "a fortnights time.". The revised papers (through Prop XXXIII) would be delivered by Cotes neighbor Whiston in September when he returned from London. *Correspondence of Sir Isaac Newton and Professor Cotes, pg 3

1783 The 1783 Great Meteor was an unusually bright Bolide observed on August 18, 1783, from the British Isles at a time when such phenomena were not well understood. The meteor was the subject of much discussion in the Philosophical Transactions of the Royal Society and was the subject of a detailed study by Charles Blagden. *Wik Christopher Goulding reproduced this Paul Sandby watercolor of the meteor as seen from the terrace of Windsor Castle on 18 August 1783. Goulding lists the observers as James Lind, the Italian physicist Dr Tiberio Cavallo (1749-1809), Dr. Lockman (the Canon of St George's, Windsor), Thomas Sandby (the brother of the artist), and two unknown women.*GeoCosmo History

1813 On August 18, 1913, at the famous Monte Carlo casino, black came up 26 times in a row. Supposedly the house made a fortune against people betting that the long overdue red HAD to show up. *PB Personal notes

In 1868, Pierre Janssan discovered helium in the solar spectrum during eclipse, but did not recognize it as a new element. The first evidence of helium was observed on August 18, 1868 as a bright yellow line with a wavelength of 587.49 nanometers in the spectrum of the chromosphere of the Sun. The line was detected by French astronomer Janssen during a total solar eclipse in Guntur, India. This line was initially assumed to be sodium. English astronomer Norman Lockyer observed a yellow line in the solar spectrum during the same eclipse, which he named the D3 Fraunhofer line because it was near the known D1 and D2 lines of sodium. He concluded that it was caused by an element in the Sun unknown on Earth. Lockyer and English chemist Edward Frankland named the element with the Greek word for the Sun, Helios. Terrestrial helium was found about 10 years later by William Ramsay. *Wik

1877 Asaph Hall discovered Phobos, a satellite of Mars. The two moons of Mars, Phobos and Deimos, were found when American astronomer Hall identified them after a long search, although their existence had been a source of speculation before. The possibility of Martian moons had been speculated long before Hall's discovery. The astronomer Johannes Kepler (1571–1630) even predicted their number correctly, although with faulty logic: he wrote that since Jupiter had four known moons and Earth had one, it was only natural that Mars should have two.
Perhaps inspired by Kepler (and quoting Kepler's third law), Jonathan Swift's satire Gulliver's Travels (1726) refers to two moons in Part 3, Chapter 3 (the "Voyage to Laputa"), in which the astronomers of Laputa are described as having discovered two satellites of Mars orbiting at distances of 3 and 5 Martian diameters, and periods of 10 and 21.5 hours, respectively. The actual orbital distances and periods of Phobos and Deimos of 1.4 and 3.5 Martian diameters, and 7.6 and 30.3 hours, respectively.
Hall discovered Deimos on August 12, 1877 at about 07:48 UTC and Phobos on August 18, 1877, at the US Naval Observatory in Washington, D.C., at about 09:14 GMT (contemporary sources, using the pre-1925 astronomical convention that began the day at noon, give the time of discovery as August 11, 14:40 and August 17 16:06 Washington mean time respectively)*Wik In the words of Asaph Hall, "Of the various names that have been proposed for these satellites, I have chosen those suggested by Mr Madan of Eton, England, viz: Deimos for the outer satellite; Phobos for the inner satellite. These are generally the names of the horses that draw the chariot of Mars.”

1881 “The matter is so perfectly clear that we cannot be amazed enough how the mathematicians so stubbornly insist on mystifying it.” Comment of Friedrich Engels on a manuscript of Karl Marx on the differential calculus. *VFR

1913 On August 18, 1913, at the famous Monte Carlo casino, black came up 26 times in a row. Supposedly the house made a fortune against people betting that the long overdue red HAD to show up. *PB Personal notes

1978 Henri Cohen gives lecture to confirm Roger Apery's proof that Apéry's constant ζ(3) is irrational. In June 1978 Roger Apéry gave a talk entitled "Sur l'irrationalité de ζ(3)." During the course of the talk he outlined proofs that ζ(3) and ζ(2) were irrational, the latter using methods simplified from those used to tackle the former rather than relying on the expression in terms of π. Due to the wholly unexpected nature of the result and Apéry's blasé and very sketchy approach to the subject many of the mathematicians in the audience dismissed the proof as flawed. Three of the audience members suspected Apéry was onto something, though, and set out to confirm his proof.
Two months later these three—Henri Cohen, Hendrik Lenstra, and Alfred van der Poorten—finished their work, and on August 18 Cohen delivered a lecture giving full details of Apéry's proof. Following the talk Apéry himself took to the podium to explain the source of some of his ideas. *Wik

BIRTHS

 *@sciencemuseum
1685 Brook Taylor born (18 August 1685 – 29 December 1731). Remembered in introductory Calculus classes for Taylor's Theorem and Taylor series. His 1713 "Methodus.." was the first book published on the calculus of finite differences and also the first use of Taylor's Theorem.
In his 1715 essay Linear Perspective, Taylor set forth the true principles of the art in an original and more general form than any of his predecessors; but the work suffered from the brevity and obscurity which affected most of his writings, and needed the elucidation bestowed on it in the treatises of John Joshua Kirby (1754) and Daniel Fournier. *Wik

1832 Eugène Rouché (18 August 1832 at Sommières, Hérault, France, -19 August 1910 at Lunel, Hérault) French Geometer who edited Laguerre's "Collected Works". He also is known for Rouche's Theorem on Complex functions. *SAU

1861 William J Greenstreet (18 Aug 1861 in Milton, Kent, England
- 28 June 1930 in Burghfield Common, Reading, England) graduated from Cambridge and became headmaster of Marling School Stroud. He is best-known as the long-running editor of the Mathematical Gazette. *SAU

1897 Bern Dibner (18 Aug 1897; 6 Jan 1988 ) Ukrainian-American engineer and science historian. Dibner worked as an engineer during the electrification of Cuba. Realizing the need for improved methods of connecting electrical conductors, in 1924, he founded the Burndy Engineering Company. A few years later, he became interested in the history of Renaissance science. Subsequently, he began collecting books and everything he could find that was related to the history of science. This became a second career as a scholar that would run parallel with his life as a businessman. He wrote many books and pamphlets, on topics from the transport of ancient obelisks, to authorative biographies of many scientific pioneers, including Volta, inventor of the electric battery, and Roentgen, discoverer of the X ray. *TIS

1910 Paul Turán (18 Aug 1910,26 Sept 1976) Paul Erdos, who co-authored many papers with Turan wrote:
Probably the most important, most enduring and most original of Turán's results are in his power sum method and its applications. I was there when it originated in 1938. Turán mentioned these problems and told me that they were not only interesting in themselves but their positive solution would have many applications. Their importance first of all is that they lead to interesting deep problems of a completely new type; they have quite unexpectedly surprising consequences in many branches of mathematics - differential equations, numerical algebra, and various branches of function theory.
In fact Turán invented the power sum method while investigating the zeta function and he first used the method to prove results about the zeros of the zeta function.*SAU

DEATHS

1652 Florimond DeBeaune died (7 October 1601, Blois – 18 August 1652, Blois). His name is attached to one of the ﬁrst problems ever posed in diﬀerential equations. *VFR DeBeaune was a friend of Descartes, and helped van Schooten write the Latin Translation of Descartes "Geometrie". De Beaune asked to find a curve for which the subtangent had a fixed length. De Beaune did not give this curve a name, but it has come to be called by his name. Leibniz solve De Beaune's question in his first paper on calculus in 1684. *Ed Sandifer, How Euler Did It. (Oct 2008)
In a 1638 letter to Descartes, de Beaune posed the problem of solving the differential equation

$\frac{\operatorname{d}y}{\operatorname{d}x}=\frac{\alpha}{y-x}$

now seen as the first example of the inverse tangent method of deducing properties of a curve from its tangents.
His Tractatus de limitibus aequationum was reprinted in England in 1807; in it, he finds upper and lower bounds for the solutions to quadratic equations and cubic equations, as simple functions of the coefficients of these equations. His Doctrine de l'angle solide and Inventaire de sa bibliothèque were also reprinted, in Paris in 1975. Another of his writings was Notae breves, the introduction to a 1649 edition of Descartes' La Géométrie. *Wik

1823 André-Jacques Garnerin (31 Jan 1769, 18 Aug 1823) French aeronaut, the first person to use a parachute regularly and successfully. He perfected the parachute and made jumps from greater altitudes than had been possible before. On 22 October 1797, at age 28, Garnerin made his first jump above the Parc Monceau in Paris. He dropped from a hot-air balloon at 3000 feet. His parachute, with 36 ribs and lines, was semi-rigid, somewhat resembling an umbrella. The descent was a success, except that he shook back and forth violently while falling. The physicist Lalande, who attended the event, suggested improving air flow with a small opening at the top of the canopy. Garnerin died aged 41. While preparing balloon equipment, a beam struck his head inflicting a mortal wound. *TIS

1960 Carlo Emilio Bonferroni (28 Jan 1892 in Bergamo, Italy - 18 Aug 1960 in Florence, Italy) His articles are more of a contribution to probability theory than to simultaneous statistical inference. He also had interests in the foundations of probability. He developed a strongly frequentist view of probability denying that subjectivist views can even be the subject of mathematical probability. *SAU He is best known for the Bonferroni inequalities, and gives his name to (but did not devise) the Bonferroni correction in statistics. *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

Thursday, 17 August 2017

On This Day in Math - August 17

Base eight is just like base ten, really… if you're missing two fingers!
~Tom Lehrer, "New Math"

The 229th day of the year; 229 is a prime, and is the smallest prime that added up to the reversal of its digits yields another prime, (229 + 922) = 1151 (can you find the next one?)

The sum of the digits of 229 is prime (13) and the sum of squares of the digits is also prime (89).

extra: 229 is the difference between 3³ and 4⁴ *jim wilder ‏@wilderlab

EVENTS

1585 The Roanoak Colony in Virginia (to later become known as the "lost" colony) was founded on this day by Sir Walter Raleigh's agents, led by Ralph Lane. If you don't know why that is on a math page, read more here.

1655 William Oughtred writes to John Wallis to praise his methods in "Arithmetica Infinitorum" . It was received too late to be included in the first edition, but was included in the 1695 second edition.  *The Arithmetics of Infinitesimals, J. Stedall, pg 11

1762 The Board of Longitude Grants £500 to Christopher Irwin for his marine chair. Marine chairs, despite often having been ignored by modern scholars in favor of the chronometer and lunar-distance approaches to estimating longitude, reappeared throughout the history of the British Commissioners of the Longitude. Christopher Irwin of Ireland generated a lot of national and international interest in the late 1750s and early 1760s with his design. The Board funded the finishing and sea trial of it, granting him £500 on 17 August 1762. Nevil Maskelyne considered the chair alongside the lunar-distance method and one of John Harrison's longitude timekeepers on his 1763 trip to Barbados. (Maskelyne, who in 1765 would become Astronomer Royal and a Commissioner of Longitude, reported that the invention was useless. *Cambridge Digital Library

1771 Joseph Priestley sets out to test the rejuvenating effect of mint growing in a sealed container. He placed a candle in the covered glass and let it burn out in the presence of the mint. Ten days later he would return to the experiment and relight the candle and found, "it burned perfectly well in it." *Steven Johnson, The Invention of Air

1811 “Having to conduct my grandson through his course of mathematics, I have resumed the study with great avidity. It was ever my favorite one. We have no theories there, no uncertainties remain on the mind; all is demonstration and satisfaction.” So wrote Thomas Jefferson (1743– 1826) to Benjamin Rush. Taken from The Writings of Thomas Jefferson, edited by A. A. Lipscomb, vol. 13 (1903), p. 75, as quoted from Cajori, Mathematics in Liberal Education, p. 109, which is a collection of interesting quotations on the value of mathematics.  The following year, his 70th, Jefferson describes his early affection for mathematics in a letter to William Duane "When I was young, mathematics was the passion of my life." *John Fauval, lecture at Univ of Va.

1825 A royal decree granted Niels Henrik Abel, then 23, sufficient funds for a year’s travel in France and Germany. *VFR

1877 Asaph Hall discovered Phobos, inner satellite of Mars. The two moons of Mars, Phobos and Deimos, were found when American astronomer Hall identified them after a long search, although their existence had been a source of speculation before. The possibility of Martian moons had been speculated long before Hall's discovery. The astronomer Johannes Kepler (1571–1630) even predicted their number correctly, although with faulty logic: he wrote that since Jupiter had four known moons and Earth had one, it was only natural that Mars should have two.
Perhaps inspired by Kepler (and quoting Kepler's third law), Jonathan Swift's satire Gulliver's Travels (1726) refers to two moons in Part 3, Chapter 3 (the "Voyage to Laputa"), in which the astronomers of Laputa are described as having discovered two satellites of Mars orbiting at distances of 3 and 5 Martian diameters, and periods of 10 and 21.5 hours, respectively. The actual orbital distances and periods of Phobos and Deimos of 1.4 and 3.5 Martian diameters, and 7.6 and 30.3 hours, respectively.
Hall discovered Deimos on August 12, 1877 at about 07:48 UTC and Phobos on August 18, 1877, at the US Naval Observatory in Washington, D.C., at about 09:14 GMT (contemporary sources, using the pre-1925 astronomical convention that began the day at noon, give the time of discovery as August 11, 14:40 and August 17 16:06 Washington mean time respectively)*Wik
In the words of Asaph Hall, "Of the various names that have been proposed for these satellites, I have chosen those suggested by Mr Madan of Eton, England, viz: Deimos for the outer satellite; Phobos for the inner satellite. These are generally the names of the horses that draw the chariot of Mars. "

1896 Mrs. Bridget Driscoll of Croydon, Surrey, became the 1st pedestrian in Britain to die after being hit by a car. Mrs Driscoll, a 44 year old housewife, who was traveling from Old Town, Croydon to a folk-dancing display in Crystal Palace, was hit by a demonstration car traveling at 4mph (according to the driver, Arthur Edsel) . She died within minutes of receiving a head injury.
At her inquest, Coroner William Percy Morrison said he hoped that "such a thing would never happen again" and was the first to apply the term ‘accident’ to violence caused by speed. Coroners across the country have followed his example ever since. *Road Safety Center Cardiff.

1934 Dunham Jackson personalizes a book. Harold Bacon recalls that Jackson was an inspired writer of limericks. When Bacon purchased Jackson's "The Theory of Approximations" he took it to Jackson's office and requested he sign it, suggesting a limerick. Without any visible prethought Jackson wrote on the flyleaf:
There was a young fellow named Bacon
Whose judgement of books was mistaken
In a moment too rash
He relinquished some cash
And his faith in the Author was shaken
August 17, 1934
*Steven Krantz, Mathematical Apocrypha Redux
Harold M Bacon was a long-serving calculus professor at Stanford where a teaching award in his name has been created since his death in 1992.

1941 When Herbert Robbins saw the proof sheet of the title page of What is Mathematics? with only the name Richard Courant on it, his ﬁrst reaction was “My god, the man’s a crook.” Realizing that a quiet meeting on their co-authorship of the book would be impossible, Robbins wrote Courant on this date that, while the custom might be different in Europe, in this country the junior author did receive credit. Courant backed down, and so today we know this lovely book as one by Courant and Robbins. For the two sides of this story see Constance Reid, Courant in Gottingen and New York. The Story of an Improbable Mathematician (Springer 1976), 223– 226 and 230–232 as well as “An interview with Herbert Robbins,” The College Mathematics Journal, 15(1984), 4–6. *VFR

1966 Launch of Pioneer 7, American solar satellite. Studied prominences and solar atmosphere. *NSEC

BIRTHS
1601 Pierre de Fermat (17 Aug 1601; 12 Jan 1665) French mathematician, often called the founder of the modern theory of numbers. Together with Rene Descartes, Fermat was one of the two leading mathematicians of the first half of the 17th century. He anticipated differential calculus with his method of finding the greatest and least ordinates of curved lines. He proposed the famous Fermat's Last Theorem while studying the work of the ancient Greek mathematician Diophantus. He wrote in pencil in the margin, "I have discovered a truly remarkable proof which this margin is too small to contain," that when the Pythagorean theorem is altered to read an + bn = cn, the new equation cannot be solved in integers for any value of n > 2 . *TIS

1936 Margaret Heafield Hamilton (August 17, 1936 - ) is a computer scientist, systems engineer and business owner. She was Director of the Software Engineering Division of the MIT Instrumentation Laboratory, which developed on-board flight software for the Apollo space program. In 1986, she became the founder and CEO of Hamilton Technologies, Inc. in Cambridge, Massachusetts. The company was developed around the Universal Systems Language based on her paradigm of Development Before the Fact (DBTF) for systems and software design.
In one of the critical moments of the Apollo 11 mission, Hamilton's team's work prevented an abort of the landing on the Moon. Among other things, Hamilton credits the Apollo Guidance Computer (AGC) together with its asynchronous executive as a foundation that provided the means for her to design systems software that included AGC error detection and recovery mechanisms such as the Display Interface Routines, the purpose of which was to warn the astronauts in case of an emergency, by interrupting the astronaut's normal mission sequence displays and replacing them with priority displays (e.g., the priority displays of the 1201 and 1202 alarms that took place during the Apollo 11 landing). Three minutes before the Lunar lander reached the Moon's surface, several computer alarms were triggered. The computer was overloaded with incoming data, because the rendezvous radar system (not necessary for landing) updated an involuntary counter in the computer, which stole cycles from the computer. Due to its robust architecture, the computer was able to keep running; the Apollo onboard flight software was developed using an asynchronous executive so that higher priority jobs (important for landing) could interrupt lower priority jobs.

Hamilton has published over 130 papers, proceedings, and reports concerned with the 60 projects and six major programs in which she has been involved. *Wik

1954 Ingrid Daubechies ( born 17 August 1954- ) is a Belgian physicist and mathematician. She is currently Professor in the mathematics and applied mathematics departments at Princeton University. In January 2011 she moved to Duke University as a Professor in mathematics. She is the first woman president of the International Mathematical Union (2011–2014). She is best known for her work with wavelets in image compression. In 2000 Daubechies became the first woman to receive the National Academy of Sciences Award in Mathematics, presented every 4 years for excellence in published mathematical research. The award honored her "for fundamental discoveries on wavelets and wavelet expansions and for her role in making wavelets methods a practical basic tool of applied mathematics."
In January 2005, Daubechies became just the third woman since 1924 to give the Josiah Willard Gibbs Lecture sponsored by the American Mathematical Society. Her talk was on "The Interplay Between Analysis and Algorithm."*Wik

DEATHS

1786 Death of Frederick the Great. Euler's interest in lotteries began at the latest in 1749 when he was commissioned by Frederick the Great to render an opinion on a proposed lottery. The first of two letters began 15 September 1749. A second series began on 17 August 1763.

1924 Pavel Samuilovich Urysohn, Pavel Uryson (February 3, 1898, Odessa – August 17, 1924, Batz-sur-Mer) is best known for his contributions in the theory of dimension, and for developing Urysohn's Metrization Theorem and Urysohn's Lemma, both of which are fundamental results in topology. His name is also commemorated in the term Menger-Urysohn dimension and in the term Urysohn integral equation. The modern definition of compactness was given by him and Pavel Alexandrov in 1923.*Wik

1927 (Erik) Ivar Fredholm (7 Apr 1866,17 Aug 1927) Swedish mathematician who founded modern integral equation theory. *TIS

1969 Otto Stern (17 Feb 1888; 17 Aug 1969 at age 81) German-American scientist and winner of the Nobel Prize for Physics in 1943 for his development of the molecular beam as a tool for studying the characteristics of molecules and for his measurement of the magnetic moment of the proton. *TIS

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

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, 16 August 2017

On This Day in Math - August 16

Projective geometry is all geometry.
~Arthur Cayley

The 228th day of the year; 228 is the number of ways, up to rotation and reflection, of dissecting a regular 11-gon into 9 triangles.

228 + 1,  822 + 1, and (228 + 822) + 1 are all primes. Is there another such year day?

228 in binary is written 11100100 notice that this is all four possible two digit binary combinations in descending order, 11, 10, 01, 00.

EVENTS

1878 Hermite writes to Sylvester at Johns Hopkins concerned about his accepting a Math Chair in America to questioned the ability of the American people to contribute to research-level mathematics. Only three years later he would be reading the paper of Fabian Franklin, a young assistant mathematics instructor at Johns Hopkins, before the French Academy. The paper was on a short, purely graphic, proof of Euler's theorem on pentagonal numbers. *Karen Hunger Parshall, David E. Rowe; The Emergence of the American Mathematical Research Community, 1876-1900

In 1898, the loop-de-loop Roller Coaster was patented by Edwin Prescott.*TIS The vertical loop is not a recent roller coaster innovation. Its origins can be traced back to the 1850s when centrifugal railways were built in France and Great Britain. In 1901 Prescott built the Loop-the-Loop at Coney Island. This ride used the modern teardrop-shaped loop and a steel structure, however more people wanted to watch the attraction, rather than ride. No more looping roller coasters were built until 1976 when Revolution opened at Six Flags Magic Mountain.*Wik

1966 Stephen Smale, University of California, Berkeley, received the Fields Medal at the International Congress of Mathematicians in Moscow for his work on dynamical systems. Ten days later on the steps of Moscow University he will make a speech condemning American
military activity in Vietnam and Soviet military involvement in Hungary. *VFR

1983 Poland issued a stamp celebrating the 50th anniversary of the Enigma Decoding Machine. VFR

BIRTHS

1744 Pierre (-François-André) Méchain (16 Aug 1744; 20 Sep 1804). a French astronomer and hydrographer at the naval map archives in Paris recruited by Jean Delambre. He was a mathematical progidy. In 1790, they were chosen by the National Assembly to establish a decimal system of measurement based on the meter. Since this was defined to be one ten-millionth of the distance between the Earth's pole and the equator, Mechain led a survey of the meridian arc from Dunkirk, France, to Barcelona, Spain. Through his astronomical observations, Mechain discovered 11 comets and provided 26 additions to Messier's catalog. He calculated the orbits of the two comets he found in 1781. Mechain died of yellow fever while making further surveys for the meridian measurement. *TIS

1821 Arthur Cayley, (16 August 1821 – 26 January 1895) English mathematician who played a leading role in founding the modern British school of pure mathematics. He trained first as a lawyer, and from 1849, spent 14 years at the bar, during which time he maintained an interest in mathematics and published about 250 mathematical papers. In 1863, Cayley followed his passion and commenced a new career as professor of Pure Mathematics at Cambridge and during his tenure published 900 papers and notes covering nearly every aspect of modern mathematics. The legacy of his work in n-dimensional geometry was later applied in physics to the study of the space-time continuum. His work on matrices served as a foundation for quantum mechanics developed by Werner Heisenberg in 1925. *TIS

1836 Marc-Antoine Parseval des Chênes (April 27, 1755 – August 16, 1836) was a French mathematician, most famous for what is now known as Parseval's theorem, which presaged the unitarity of the Fourier transform.
He was nominated to the French Academy of Sciences five times, from 1796 to 1828, but was never elected. His only mathematical publications were, apparently, five papers, published in 1806 as Mémoires présentés à l'Institut des Sciences, Lettres et Arts, par divers savants, et lus dans ses assemblées. Sciences mathématiques et physiques. (Savants étrangers.) This combined the following earlier monographs:
1. "Mémoire sur la résolution des équations aux différences partielles linéaires du second ordre," (May 5, 1798).
2. "Mémoire sur les séries et sur l'intégration complète d'une équation aux différences partielles linéaires du second ordre, à coefficients constants," (April 5, 1799).
3. "Intégration générale et complète des équations de la propagation du son, l'air étant considéré avec ses trois dimensions," (July 5, 1801).
4. "Intégration générale et complète de deux équations importantes dans la mécanique des fluides," (August 16, 1803).
5. "Méthode générale pour sommer, par le moyen des intégrales définies, la suite donnée par le théorème de M. Lagrange, au moyen de laquelle il trouve une valeur qui satisfait à une équation algébrique ou transcendante," (May 7, 1804).
It was in the second, 1799, memoir in which he stated, but did not prove (claiming it to be self-evident), the theorem that now bears his name. He further expanded upon it in his 1801 memoir, and used it to solve various differential equations. The theorem was first printed in 1800 as a part (p. 377) of Traité des différences et des séries by Lacroix.
*Wik

1837 Joseph-Marie de Tilly,(16 Aug 1837 in Ypres, Belgium - 4 Aug 1906 in Munich, Germany) Belgian mathematician, born. In 1899 he was dismissed from his teaching post at the Ecole Militaire for unduly emphasizing the scientific education of future officers and using the notions of the inﬁnitely small and the differential. *VFR

1845 Gabriel Lippman (16 Aug 1845; 13 Jul 1921).French physicist, born Hollerich, Luxembourg, who received the Nobel Prize for Physics in 1908 for producing the first colour photographic plate. Lippmann was a giant of his day in classical physics research, especially in optics and electricity. He worked in Berlin with the famed Hermann von Helmholtz before settling in Paris to head (in 1886) the Sorbonne's Laboratories of Physical Research until his death. His inventions include an instrument for precisely measuring minute differences in electrical power and the "coleostat" for steady, long-exposure sky photography.*TIS

1884 Hugo Gernsback (August 16, 1884 – August 19, 1967), born Hugo Gernsbacher, was a Luxembourgish-American inventor, writer, editor, and magazine publisher, best known for publications including the first science fiction magazine. His contributions to the genre as publisher were so significant that, along with the novelists H. G. Wells and Jules Verne, he is sometimes called "The Father of Science Fiction". In his honour, annual awards presented at the World Science Fiction Convention are named the "Hugos" *Wik

1904 Wendell Meredith Stanley (16 August 1904 – 15 June 1971) was an American biochemist, virologist and Nobel laureate. Stanley was born in Ridgeville, Indiana, and earned a BS in Chemistry at Earlham College in Richmond, Indiana. He then studied at the University of Illinois, gaining an MS in science in 1927 followed by a Ph.D. in chemistry two years later. His later accomplishments include writing the book "Chemistry: A Beautiful Thing" and achieving his high stature as a Pulitzer Prize nominee.
Stanley was awarded the Nobel Prize in Chemistry for 1946. His other notable awards included the Rosenburger Medal, Alder Prize, Scott Award, and the AMA Scientific Achievement Award. He was also awarded honorary degrees by many universities both American and foreign, including Harvard, Yale, Princeton and the University of Paris. Most of the conclusions Stanley had presented in his Nobel-winning research were soon shown to be incorrect (in particular, that the crystals of mosaic virus he had isolated were pure protein, and assembled by autocatalysis)
Stanley married Marian Staples (1905-1984) in 1929 and had three daughters (Marjorie, Dorothy and Janet), and a son, (Wendell M. Junior). Stanley Hall at UC Berkeley (now Stanley Biosciences and Bioengineering Facility) and Stanley Hall at Earlham College are named in his honor. *Win

1905 Marian Adam Rejewski (16 August 1905 – 13 February 1980) was a Polish mathematician and cryptologist who in 1932 solved the plugboard-equipped Enigma machine, the main cipher device used by Germany. The success of Rejewski and his colleagues Jerzy Różycki and Henryk Zygalski jump-started British reading of Enigma in World War II; the intelligence so gained, code-named "Ultra", contributed, perhaps decisively, to the defeat of Nazi Germany.
While studying mathematics at Poznań University, Rejewski had attended a secret cryptology course conducted by the Polish General Staff's Biuro Szyfrów (Cipher Bureau), which he joined full-time in 1932. The Bureau had achieved little success reading Enigma and in late 1932 set Rejewski to work on the problem. After only a few weeks, he deduced the secret internal wiring of the Enigma. Rejewski and his two mathematician colleagues then developed an assortment of techniques for the regular decryption of Enigma messages. Rejewski's contributions included devising the cryptologic "card catalog," derived using his "cyclometer," and the "cryptologic bomb."
Five weeks before the German invasion of Poland in 1939, Rejewski and his colleagues presented their results on Enigma decryption to French and British intelligence representatives. Shortly after the outbreak of war, the Polish cryptologists were evacuated to France, where they continued their work in collaboration with the British and French. They were again compelled to evacuate after the fall of France in June 1940, but within months returned to work undercover in Vichy France. After the country was fully occupied by Germany in November 1942, Rejewski and fellow mathematician Henryk Zygalski fled, via Spain, Portugal and Gibraltar, to Britain. There they worked at a Polish Army unit, solving low-level German ciphers. In 1946 Rejewski returned to his family in Poland and worked as an accountant, remaining silent about his cryptologic work until 1967. *Wik

1907 Dura Kurep (16 Aug 1907, 2 Nov 1993)The topics which Kurepa investigated are very varied but lie mostly within topology, set theory and number theory. He published over 200 papers but this number rises to over 700 items if we include books, articles and reviews. He was fascinated by the continuum hypothesis and the axiom of choice. Perhaps best known is his work on trees and partitions, especially Aronszajn and Suslin trees. His book The Theory of Sets written in Serbo-Croatian and published in 1951 illustrates his interests in that particular area. After introducing the fundamental concepts and elementary operations in Chapter 1, he looks at cardinal numbers in the second chapter, then partially ordered sets and ordinal numbers in the third. Chapter 4 is on topological and metric spaces, with the fifth and final chapter on limiting processes in analysis, measure theory, Borel and Souslin sets.
In number theory he made many contributions, but perhaps his most famous is his open problem on the left factorial function. In 1971 he published his definition of !n, the left factorial function, defined by
!n = 0! + 1! + 2! + 3! + ... + (n-1)!.
Kurepa conjectured that the greatest common divisor of !n and n! was 2 for all n > 1. There are many equivalent forms of the conjecture, but one of the most natural was given by Kurepa in the same 1971 paper, namely that !n is not divisible by n for any n > 2. If the left factorial conjecture is false we certainly know that it will fail for n > 1000000.*SAU
The same left factorial notation is more commonly used for the subfactorial used in derangements. Many mathematicians simply use "factorial sum" for Kurepa's !n. It is interesting that no one seems to have picked up on the use of an inverted exclamation point as suggested by G. Chrystal in his "Algebra, an Elementary Textbook for the Higher Classes of Secondary Schools and for Colleges", (1889 (pg 25))

1920 Richard Ernest Bellman (August 26, 1920 – March 19, 1984) was an American applied mathematician, celebrated for his invention of dynamic programming in 1953, and important contributions in other fields of mathematics. A Bellman equation, also known as a dynamic programming equation, is a necessary condition for optimality associated with the mathematical optimization method known as dynamic programming. Almost any problem which can be solved using optimal control theory can also be solved by analyzing the appropriate Bellman equation. The Bellman equation was first applied to engineering control theory and to other topics in applied mathematics, and subsequently became an important tool in economic theory. The "Curse of dimensionality", is a term coined by Bellman to describe the problem caused by the exponential increase in volume associated with adding extra dimensions to a (mathematical) space.*Wik

DEATHS

1705 Jakob Bernoulli . (27 December 1654 – 16 August 1705) He was so fascinated with the way the logarithmic spiral reproduces itself in its involute, its evolute, and its caustics of reﬂection and refraction, that he requested it be engraved on his tombstone, together with the inscription Eadem mutata resurgo (Though changed, I will arise the same). *VFR (the spiral on his tombstone is not logarithmic, but Archimedian... perhaps he is spinning in his grave even yet.)
He was one of the first to fully utilize differential calculus and introduced the term "integral" in integral calculus. Jacob Bernoulli's first important contributions were a pamphlet on the parallels of logic and algebra (1685), work on probability in 1685 and geometry in 1687. His geometry result gave a construction to divide any
triangle into four equal parts with two perpendicular lines.(a nice exercise to try) By 1689 he had published important work on infinite series and published his law of large numbers in probability theory. He published five treatises on infinite series (1682 - 1704). He was the first of the Bernoulli family of mathematicians. *TIS
Jacob Bernoulli’s Ars Conjectandi from 1713 is the first major book on the theory of probability and statistics. It is because of its 300 years anniversary that 2013 was named the international year of Statistics. The exhibited copy is in fact a first edition! It is showing the proof of the law of large numbers, one of the results for which it is famous. * University of Copenhagen Dept of Math Sciences

1920 Sir Joseph Norman Lockyer (17 May 1836, 16 Aug 1920) British astronomer who in 1868 discovered and named the element helium that he found in the Sun's atmosphere before it had been detected on Earth. He also applied the name chromosphere for the sun's outer layer. Lockyer discovered, together with Pierre J. Janssen, the prominences (red flames) that surround the solar disk. He was also interested in the classification of stellar spectra and developed the meteoric hypothesis of stellar evolution. His works include the books Contributions to Solar Physics (1873), The Sun's Place in Nature (1897) and Inorganic Evolution (1900). *TIS

1995 Thomas Brooke Benjamin​, FRS (15 April 1929 – 16 August 1995) was an English mathematical physicist and mathematician, best known for his work in mathematical analysis and fluid mechanics, especially in applications of nonlinear differential equations. *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