Friday, 4 September 2026

Excel Will Outlive Us All


Just came across a really interesting blog for Data Analytics and Statistics folks, and offering up a sample of the most recent blog.  


Excel Will Outlive Us All, And Data Analysts Can't Escape It




If you’re learning data analytics, it won’t take long before someone tells you Excel is “outdated” or “not a real data tool.”


Ignore them.


Excel isn’t going anywhere, even if you hope that it did.



While you might assume that SQL or Power BI and Tableau will occupy your work, the fact is that Excel will be used at some point, and there are some pretty good reasons why.



There is no data role "too advanced" to use spreadsheets. Even a simple request from a stakeholder to provide an output in CSV will be a reason for its continued usage.



Some companies even use Excel as their main reporting tool (something I know all too well).



Why?



Because it’s simple, flexible, and nearly everyone knows how to open a spreadsheet.



I work in government now. I’ve worked in finance. I know people in retail, healthcare, manufacturing, education, non-profits... And you know what? Excel is in all of those industries.



I'd even go as far as to say it’s one of the most important tools you can know as a data analyst. And no, I am not saying it is THE most important tool, but it is one of them, because it’s often the fastest and easiest way to:


Clean up a small, messy dataset.


QA (quality assure) a new report.


Do a quick calculation before a meeting.


Create a draft of a dashboard layout.


Share results with people who don’t have access to BI tools.


And even people in Tableau or Power BI-heavy organizations will pull some data into Excel because... well, sometimes you just need a quick look or an offline copy.



So instead of thinking Excel is just another "basic" tool, why not learn what makes it so useful?



Keep reading and I'll share what you should know.


======================================================

And that is exactly what she does.  So if your a Data-Sort, check it out.


On This Day in Math - September 4

  


The science of pure mathematics may claim to be the most original creation of the human spirit.
~A. N. Whitehead

The 247th day of the year; 247 is the smallest number which can be expressed as the difference between two integers such that together, they contain all digits 0-9. (spoilerthe two numbers are written at the bottom of this post)

The digits of 247 sum to its smallest prime factor (247 = 13 x 19 and 2 + 4 + 7 = 13) *Prime Curios (How many of the composite days of the year sum to one of their prime factors?)

247 is the 13th Pentagonal number ( n x (3n-1)/2) . The average of the first n pentagonal numbers, is the nth Triangular number. Like all pentagonal numbers, it is the sum of the n consecutive numbers starting with n. so the 13th pentagonal number is 13 + 14 + 15 + ... 25 = 247


See More Math Facts about every Year Day Here



EVENTS




No date on this.  I found it on the LinkedIn account of Tao (Steven) Zheng and loved the ideas.  


"In traditional Chinese cosmology, the compass and square are the primary tools of creation held by the creator deities Fú xī 伏羲 and Nǚ wā 女媧, symbolizing the establishment of cosmic and moral order. Fuxi holds the jǔ 矩, or try-square, to represent the Earth, while Nüwa holds the guī 規, or compass, to represent the heavens and the celestial circle. This is the origin of the Chinese saying tiān yuán dì fāng 天圓地方 (Heaven is round, Earth is square).

The combined term for these tools, guī jǔ 規矩, which literally means “compass and try-square”, figuratively translates to rules, standards, moral behaviour, and good conduct. This metaphor originates from ancient carpentry, where these instruments were necessary to draw perfect right angles and circles. The Confucian philosopher Mencius (c. 371 – 289 BC) adopted the term guī jǔ 規矩 to describe how sages establish proper human relations and ethical standards:"  






1675 John Collins, after mentioning Tschirnhaus in a letter to James Gregory, writes: “... there being present with him a Dane named George Moorh who lately published in low Dutch, two little Books the one named Euclides Danicus where he pretends to perform all Euclids problems with a paire of Compasses only without Ruler, and another entitled Euclides Curiosus, wherein with a Ruler and a forke (or the Compasses at one opening) he performs the same ... ” See MT 53(1960), 127–132. (Mohr was a friend of Tschirnhaus, and he spent his last few years as a guest in his house.)

Mohr’s priority was uncovered only in the 20th century (by a Danish mathematician named Julius Petersen in 1928.   Peterson was an early influence on Graph theory, and the Peterson graph is named for him.).

This book, proving the Mohr–Mascheroni theorem 125 years earlier than Lorenzo Mascheroni, would languish in obscurity until its rediscovery in 1928.


*Wik



1740, Philip Naudé the younger (1684-1747) wrote Euler from Berlin to ask “how many ways can the number 50 be written as a sum of seven different positive integers?” The problem seems to have captured Euler’s imagination. Euler gave his first answer on April 6, 1741, in a paper he read at the weekly meeting of the St. Petersburg Academy. (Wm Dunham says that Euler replied by mail within a few days, and apologized for the delay as he had been suffering from poor eyesight.) That paper was published ten years later and is number 158 on Eneström’s index. Euler solved the problem in a different way in the Introductio in analysin infinitorum, E101,published in 1748, and made more improvements in a paper De partitione numerorum, “On the partition of numbers,” E191, written in 1750, published in 1753. Late in his life, in 1769, he returned to the problem in De partione numerorum in partes tam numero quam specie datas, “On the partition of 2 numbers into a given kind or number of parts,” E394, published in 1770. *Ed Sandifer, How Euler Did It ( A single letter revisited and the solution expanded over a thirty year period. Euler was a little of a mathematical bulldog.)(Euler got 522 for the answer to Naude's question)

Restricted partitions satisfy some additional condition. Notable among these are distinct partitions, where each summand is different, and odd partitions, where each summand is odd. For each positive number, the number of partitions with odd parts is equal to the number of partitions with distinct parts, denoted by {d(n)}. This result was proved by Leonhard Euler in 1748.




1749  Voltaire wrote to one of Émilie du Châtelet's friends :-

Mme du Châtelet informs you that this night, being at her desk working on Newton, she felt a little call. The little call was a daughter, who appeared in an instant. She was laid on a quarto book of geometry. The mother has gone to lie down and, if she were not asleep, she would be writing to you.

Sadly, du Châtelet died 6 days later.

*MacTutor, SAU

Mme du Châtelet translated Newton’s Principia Mathematica into French—a translation still used today—while Voltaire popularized Newton’s ideas in France with her help. She also critiqued and shaped many of his works through discussion and collaboration.  PBnotes

Portrait by Maurice Quentin de La Tour



1751 Leonhard Euler writes to Christian Goldbach with a conjecture about the number of dissections of a polygon into triangles by using diagonals.  He would continue to work on the problem and would eventually share the concept with Johann Andreas von Segner. In the Goldbach letter, Euler gave a product formula for the seqeunce that is now commonly called the Catalan Numbers.\( \frac{2 * 6 * 10 \dots  (4n-10}{2*3*4 \dots (n-1}\). Segner was the first to give the recursive formula .

The sequence is named after Eugène Charles Catalan, who discovered the connection to parenthesized expressions during his exploration of the Towers of Hanoi puzzle. 

The name “Catalan numbers” originated from John Riordan  (April 22, 1903 – August 27, 1988).

In 1988, it came to light that the Catalan number sequence had been used in China by the Mongolian mathematician Mingantu by 1730


1821 On  September 4th, 1821, Michael Faraday discovered that a vertically mounted wire carrying an electric current would rotate continuously round a magnet sticking out of a bowl of mercury. He named this phenomenon electro-magnetic rotations. *engineering-timelines.com




1865 First Department Store, The Bon Marché, (French: “Good Buy”), department store in Paris, founded as a small shop in the early 19th century. By about 1865 it had become the world’s first true department store. In 1876 the shop was given a new building, with skylighted interior courts, designed by the engineer Alexandre-Gustave Eiffel and architect Louis-Auguste Boileau.

Other Early Contenders for the First Department Store:

Mitsukoshi (Tokyo, 1673): Originating as the Echigoya kimono shop, it evolved over centuries into a full department store, making it the oldest retail business ancestor to transition into the department store model.

Harding, Howell & Co. (London, 1796): Located at 89 Pall Mall, this Georgian enterprise is widely considered the first true department store because it was divided into distinct specialized departments for furs, jewelry, millinery, and haberdashery. Users on Quora generally reach a consensus that this was the earliest modern precursor. 

Le Bon Marche'



1893 “The proof of the transcendency of π will hardly diminish the number of circle-squarers, however; for this class of people has always shown an absolute distrust of mathematicians and a contempt for mathematics that cannot be overcome by any amount of demonstration.” Felix Klein in The Evanston Colloquium. Lectures on Mathematics (1894), pp. 52–53. *VFR

In his old age, the English philosopher Thomas Hobbes convinced himself that he had succeeded in squaring the circle, a claim refuted by John Wallis as part of the Hobbes–Wallis controversy. During the 18th and 19th century, the false notions that the problem of squaring the circle was somehow related to the longitude problem, and that a large reward would be given for a solution, became prevalent among would-be circle squarers.

Even after it had been proved impossible, in 1894, amateur mathematician Edwin J. Goodwin claimed that he had developed a method to square the circle. The technique he developed did not accurately square the circle, and provided an incorrect area of the circle which essentially redefined 𝜋 as equal to 3.2. Goodwin then proposed the Indiana pi bill in the Indiana state legislature allowing the state to use his method in education without paying royalties to him. The bill passed with no objections in the state house, but the bill was tabled and never voted on in the Senate, amid increasing ridicule from the press.

Felix Klein



1899 A 1904 academic calendar marked this day as the day Dedekind died. He wrote the publisher saying that while 4 September might be correct, 1899 certainly was not, for on that day he had enjoyed a stimulating mathematical discussion with his dinner guest and honored friend, Georg Cantor. *VFR

Dedekind




1963 India issued a stamp honoring Dadabhoy Naoroji (1825–1917), mathematician and stateman. [Scott #376]. *VFR


1988 Only a few seconds before ignition, a computer halts an engine test in preparation for the launch of the space shuttle Discovery. The shuttle engine's computerized controllers determined that a valve was not closing fast enough and sent a major component failure command from the computer to all three engines, telling them not to fire. The test and computer system were part of NASA efforts to ensure the safety of Discovery, whose flight would be the first since the Challenger explosion in 1986. *CHM




BIRTHS


973 Al-Biruni born (born 5 September 973 in Kath, Khwarezm, now region in Uzbekistan, died 13 December 1048 in Ghazni). He wrote 15 works on mathematics, three of which are extant.*VFR
Al-Biruni is regarded as one of the greatest scholars of the medieval Islamic era and was well versed in physics, mathematics, astronomy, and natural sciences, and also distinguished himself as a historian, chronologist and linguist. He was conversant in Chorasmian, Persian, Arabic, Sanskrit and Turkic, and also knew Greek, Hebrew and Syriac. He spent a large part of his life in Ghazni in modern-day Afghanistan, capital of the Ghaznavid dynasty which ruled eastern Iranian lands and the northwestern Indian subcontinent. In 1017 he traveled to the Indian subcontinent and became the most important interpreter of Indian science to the Islamic world. He is given the titles the "founder of Indology" and the "first anthropologist". He was an impartial writer on custom and creeds of various nations, and was given the title al-Ustdadh ("The Master") for his remarkable description of early 11th-century India. He also made contributions to Earth sciences, and is regarded as the "father of geodesy" for his important contributions to that field, along with his significant contributions to geography. 

In his Codex Masudicus (1037), Al-Biruni theorized the existence of a landmass along the vast ocean between Asia and Europe, or what is today known as the Americas. He argued for its existence on the basis of his accurate estimations of the Earth's circumference and Afro-Eurasia's size, which he found spanned only two-fifths of the Earth's circumference, reasoning that the geological processes that gave rise to Eurasia must surely have given rise to lands in the vast ocean between Asia and Europe. He also theorized that at least some of the unknown landmass would lie within the known latitudes which humans could inhabit, and therefore would be inhabited.*Wik

The statue of Al-Biruni in United Nations Office in Vienna



1809 Luigi Menabrea (September 4, 1809 – May 24, 1896) was a French-born soldier and engineer who made contributions to elasticity theory and became prime-minister of Italy.*SAU

Ada Lovelace, while interested in Babbage’s machines , came to translate and annotate an article written by the Italian mathematician and engineer Luigi Federico Menabrea, “Notions sur la machine analytique de Charles Babbage” (1842; “Elements of Charles Babbage’s Analytical Machine”). Her detailed and elaborate annotations (especially her description of how the proposed Analytical Engine could be programmed to compute Bernoulli numbers) were excellent; “the Analytical Engine,” she said, “weaves algebraic patterns, just as the Jacquard-loom weaves flowers and leaves.” *Britannica




1848 Heinrich Bruns (4 Sept 1848 in Berlin, Germany - 23 Sept 1919 in Leipzig, Germany) was interested in astronomy, mathematics and geodesy and worked on the three body problem showing that the series solutions of the Lagrange equations can change between convergent to divergent for small perturbations of the constants on which the coefficients of the time depend..*SAU




1890 Johannes Gaultherus van der Corput (4 September 1890 – 13 September 1975) was a Dutch mathematician, working in the field of analytic number theory.

He was appointed professor at the University of Fribourg (Switzerland) in 1922, at the University of Groningen in 1923, and at the University of Amsterdam in 1946. He was one of the founders of the Mathematisch Centrum in Amsterdam, of which he also was the first director. From 1953 on, Van der Corput worked in the United States at the University of California, Berkeley, and the University of Wisconsin–Madison.

Van der Corput introduced the Van der Corput lemma, a technique for creating an upper bound on the measure of a set drawn from harmonic analysis, and the Van der Corput theorem on equidistribution modulo 1.

He became member of the Royal Netherlands Academy of Arts and Sciences in 1929, and foreign member in 1953. He was a Plenary Speaker of the ICM in 1936 in Oslo. *Wik




1899 Hildegard Rothe-Ille, Hildegard Ille, (Sep 4, 1899– Dec 1, 1942), was a German mathematician.

She was one of Issai Schur’s doctoral students. According to Alexander Soifer, “Van der Waerden walked away from Ramseyan prehistory. Issai Schur, on the other hand, continued to produce Ramseyan mathematics, and moreover directed and inspired his PhD students Richard Rado, Hildegard Ille and Alfred Brauer to do the same.”

She received her doctorate in mathematics in 1924. Beginning on April 1, 1925, she was a year-long scholarship holder at the Kaiser Wilhelm Institute for Physics, which was headed by Albert Einstein at the time. She was the only woman to receive a scholarship from that institute in that academic year, and she received a higher scholarship than her male counterparts did.

She taught at the Chamisso school in Berlin-Schöneberg from 1926 until 1928. After marrying in 1928, due to German law she was not allowed to work for pay; however, she did review papers about mathematics. Under the name Hildegard Rothe she reviewed 40 papers which had been published between 1926 and 1928, and under the name Hildegard Rothe-Ille she reviewed 129 papers which had been published between 1930 and 1937, before having to flee from the Nazi regime in 1937.

The 1940 United States census records that she was a part-time teacher of German at William Penn College.*Wik



1906 Max Ludwig Henning Delbrück (September 4, 1906 – March 9, 1981)
Delbrück was a German-American biophysicist and Nobel laureate.
Delbrück studied astrophysics, shifting towards theoretical physics, at the University of Göttingen. After receiving his Ph.D. in 1930, he traveled through England, Denmark, and Switzerland. He met Wolfgang Pauli and Niels Bohr, who got him interested in biology.
In 1937, he moved to the United States to pursue his interests in biology, taking up research in the Biology Division at Caltech on genetics of the fruit fly Drosophila melanogaster.
Delbrück was one of the most influential people in the movement of physical scientists into biology during the 20th century. Delbrück's thinking about the physical basis of life stimulated Erwin Schrödinger to write the highly influential book, What Is Life?. Schrödinger's book was an important influence on Francis Crick, James D. Watson and Maurice Wilkins who won a Nobel prize for the discovery of the DNA double helix. *TIA

In What is Life?,Schrödinger  tried to show how some of the problems of biology could be attacked by physicists, and the example he used of a successful strategist was Delbrück. James Watson, who would co-discover the structure of DNA in 1953, had taken courses with Delbrück at Cold Spring Harbor, but he confessed that it was the Delbrück of Schrödinger’s book, not the real life Max, who was his hero and inspiration. The three leaders of the Phage Group, Delbrück (often referred to as the Pope), Hershey (the Saint) and Salvador Luria (the Priest), shared the Nobel Prize in Medicine/Physiology in 1969. *LHorg



1927 John McCarthy (September 4, 1927 – October 24, 2011) was an American computer scientist and cognitive scientist. He was one of the founders of the discipline of artificial intelligence. He co-authored the document that coined the term "artificial intelligence" (AI), developed the programming language family Lisp, significantly influenced the design of the language ALGOL, popularized time-sharing, and invented garbage collection.

McCarthy spent most of his career at Stanford University. He received many accolades and honors, such as the 1971 Turing Award for his contributions to the topic of AI, the United States National Medal of Science, and the Kyoto Prize.






DEATHS


1784 César-François Cassini de Thury Died (17 Jun 1714, 4 Sep 1784)French astronomer and geodesist (Cassini III), who continued surveying work he began while assisting his father, Jacques Cassini (Cassini II), resulting in the first topographical map of France produced by modern principles. His grandfather, Giovanni Domenico Cassini (Cassini I) discovered four satellites of Saturn, a band on planet's surface, and that its ring was subdivided. Cassini I was the first to assume effective direction (1671) of the new observatory established by the Académie Royale des Sciences in Paris, which his descendants in turn continued. Cassini III was the first official director of the observatory when the post was created by the king in 1771. His son was Jean-Dominique Cassini (Cassini IV).*TIS He produced the first reliable maps of France. *SAU




1822 Josiah Meigs (August 21, 1757 – September 4, 1822) was an American academic, journalist and government official meteorologist and mathematician, born.*Wik This freethinking Democrat left his professorship at Yale for political reasons and became president of the University of Georgia. He applied Galileo’s formula for fallen bodies to the nine day’s fall of Lucifer and his angels, to determine that Hell was 1,832,308,363 miles deep. [Struik, Origins of American Science, p. 370] *VFR




1881 George Palmer Williams (Woodstock, Vermont, April 13, 1802-Ann Arbor, September 4, 1881) He graduated Bachelor of Arts from the University of Vermont in 1825, and then studied about two years in the Theological Seminary at Andover, Massachusetts. He did not complete the course, but took up teaching, which proved to be his life work.
He was Principal of the Preparatory School at Kenyon College, Ohio, from 1827 to 1831. In 1831 he was elected to the chair of Ancient Languages in the Western University of Pennsylvania, but after two years he returned to Kenyon College, where he remained until called, in 1837, to the branch of the incipient University of Michigan at Pontiac.
In 1841, when the College proper was opened at Ann Arbor, he was made Professor of Natural Philosophy. In 1854 he was transferred to the chair of Mathematics and in 1863 to the chair of Physics. From 1875 to 1881 he was Emeritus Professor of Physics.
He received the degree of Doctor of Laws from Kenyon College in 1849. The University Senate in a memorandum relative to his death declared that: "Dr. Williams welcomed the first student that came to Ann Arbor for instruction; as President of the Faculty he gave diplomas to the first class that graduated, and from the day of his appointment to the hour of his death his official connection with the University was never broken."
In 1846 he was ordained to the ministry of the Protestant Episcopal Church; but he did no regular parish work, except for a short time in Ann Arbor. He was first and last a teacher, beloved by his colleagues and pupils and universally respected and honored.
Some years before his death the alumni raised a considerable fund, the proceeds of which were to be paid to him during his lifetime and after his death were to be used for maintaining a professorship named in honor of his memory. *Hinsdale and Demmon, History of the University of Michigan 221



1969 Marcel Riesz died (16 November 1886 – 4 September 1969) His interests ranged from functional analysis to partial differential equations, mathematical physics, number theory and algebra. Later in his career he also worked on Clifford algebras and spinors. The first period of his work, from the beginning of his doctoral research up to around the beginning of World War I, concentrated on the theory of series, in particular the summability theory of power series, trigonometric series and Dirichlet series. In 1914 he gave an interpolation formula for trigonometric polynomials. This was an important discovery and the formula now appears in most texts on interpolation. It leads to quick proofs of Bernstein's inequality and Markov's inequality. Another highlight from this period is his beautiful proof of Fatou's theorem which give conditions under which the power series of an analytic function converges to a point on its circle of convergence. *SAU




1984 Ernst Carl Gerlach Stueckelberg (February 1, 1905, September 4, 1984) was a Swiss mathematician and physicist. In 1938 he recognized that massive electrodynamics contains a hidden scalar, and formulated an affine version of what would become known as the Abelian Higgs mechanism. He also proposed the law of conservation of baryon number. In 1953 he and the mathematician Andre Petermann discovered the renormalization group.
He was awarded the Max Planck medal.*Wik




1996  Joan Elisabeth Lowther Murray, MBE (née Clarke; 24 June 1917 – 4 September 1996) was an English cryptanalyst and numismatist who worked as a code-breaker at Bletchley Park during the Second World War. Although she did not personally seek the spotlight, her role in the Enigma project that decrypted the German secret communications earned her awards and citations, such as appointment as a Member of the Order of the British Empire (MBE), in 1946.

 Clarke and Turing had been close friends since soon after they met, and continued to be until Turing's death in 1954. They shared many hobbies and had similar personalities. They became very good friends at Bletchley Park. Turing arranged their shifts so they could work together, and they also spent much of their free time together. In early 1941, Turing proposed marriage to Clarke, and subsequently introduced her to his family. Although he privately admitted his homosexuality to her—she was reportedly unfazed by the revelation—Turing decided that he could not go through with the marriage, and broke up with Clarke in mid-1941. Clarke later admitted that she suspected Turing's homosexuality for some time, and it was not much of a surprise when he made the admission to her.




2011 Hans Grauert (8 February 1930 in Haren, Emsland, Germany – 4 September 2011) was a German mathematician. He is known for major works on several complex variables, complex manifolds and the application of sheaf theory in this area, which influenced later work in algebraic geometry. Together with Reinhold Remmert he established and developed the theory of complex-analytic spaces. He became professor at the University of Göttingen in 1958, as successor to C. L. Siegel. The lineage of this chair traces back through an eminent line of mathematicians: Weyl, Hilbert, Riemann, and ultimately to Gauss. Until his death, he was professor emeritus at Göttingen.   Grauert was awarded a fellowship of the Leopoldina. *Wik




247 = 50123 - 49876



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, 3 September 2026

Updating the History of the Pigeon Hole Theorem

  


 The Pigeon Hole Principle......The basic idea behind this mathematical principle is what students would call common sense; if there are n objects to be placed in m receptacles (with m less than n), at least two of the items must go into the same container. While the idea is common sense, in the hands of a capable mathematician it can be made to do uncommon things. The late Alexander Bogomolny used the principle to argue that there must be at least two persons in New York City with the same number of hairs on their head. This "counting hairs" approach dates back to the earliest version of the principal I have ever seen.

The same axiom is often named in honor of Dirichlet who used it in solving Pell's equation. The pigeon seems to be a recent addition, as Jeff Miller's web site on the first use of some math words gives, "Pigeon-hole principle occurs in English in Paul Erdös and R. Rado, A partition calculus in set theory, Bull. Am. Math. Soc. 62 (Sept. 1956)" (although they credit Dedekind for the principle). In a recent discussion on a history group Julio Cabillon added that there are a variety of names in different countries for the idea. His list included "le principe des tiroirs de Dirichlet", French for the principle of the drawers of Dirichlet, and the Portugese "principio da casa dos pombos" for the house of pigeons principle and "das gavetas de Dirichlet" for the drawers of Dirichlet. It also is sometimes simply called Dirichlet's principle and most simply of all, the box principle. Jozef Przytycki wrote me to add, "In Polish
we use also:"the principle of the drawers of Dirichlet"
that is 'Zasada szufladkowa Dirichleta' ". I received a note that said, "Dirichlet first wrote about it in Recherches sur les formes quadratiques à coefficients et à indéterminées complexes (J. reine u. angew. Math. (24 (1842) 291 371) = Math. Werke, (1889 1897), which was reprinted by Chelsea, 1969, vol. I, pp. 533-618. On pp. 579-580, he uses the principle."

 Dirichlet


He doesn't give it a name. In later works he called it the "Schubfach Prinzip" [which I am told means "drawer principle" in German]

The idea has been around much longer than Dirichlet, however, as I found out in June of 2009 when Dave Renfro sent me word that the idea pops up in the unexpected (at least by me) work, "Portraits of the seventeenth century, historic and literary", by Charles Augustin Sainte-Beuve. During his description of Mme. de Longuevillle, who was Ann-Genevieve De Bourbon, and lived from 1619 to 1679 he tells the following story:

Anne-Geneviève de Bourbon


"I asked M. Nicole (See below for description of M. Nicole) one day what was the character of Mme. de Longueville's mind; he told me she had a very keen and very delicate mind in knowledge of the character of individuals, but that it was very small, very weak, very limited on matters of science and reasoning, and on all speculative matters in which there was no question of sentiment ' For example,' added he, ' I told her one day that I could bet and prove that there were in Paris at least two inhabitants who had the same number of hairs upon their head, though I could not point out who were those two persons. She said i could not be certain of it until I had counted the hairs of the two persons. Here is my demonstration/ I said to her: M lay it down as a fact that the best-fiimbhed (not sure what this word was supposed to be, ..Plumbed??) head does not possess more than 200,000 hairs, and the most scantily furnished head b that which has only 1 hair. If, now you suppose that 200,000 heads all have a different number of hairs, they must each have one of the numbers of hairs which are between 1 and 200,000; for if we suppose that there were 2 among these 200,000 who had the same number of hairs, I win my bet But suppose these 200,000 inhabitants all have a different number of hairs, if I bring in a single other inhabitant who has hairs and has no more than 200,000 of them, it necessarily follows that this number of hairs, whatever it b, will be found between 1 and 200,000, and, consequently, b equal in number of hairs to one of the 200,000 heads. Now, as instead of one inhabitant more than 200,000, there are, in all, nearly 800,000 inhabitants in Paris, you see plainly that there must be many heads equal in number of hairs, although I have not counted them.' Mme. de Longuevillle still could not understand that demonstration could be made of the equality in number of hairs, and she always maintained that the only way to prove it was to count them. "

The M. Nicole who demonstrated the principal was Pierre Nicole, (1625 -1695), one of the most distinguished of the French Jansenist writers, sometimes compared more favorably than Pascal for his writings on the moral reasoning of the Port Royal Jansenists. It may be that he had picked up the principal from Antoine Arnauld, another Port Royal Jansenist who was an influential mathematician and logician. Here is a segment from his bio at the St. Andrews Math History site.

P Nicole


-------------------------
He published Port-Royal Grammar in 1660 which was strongly influenced by Descartes' Regulae. In Port-Royal Grammar Arnauld argued that mental processes and grammar are virtually the same thing. Since mental processes are carried out by all human beings, he argued for a universal grammar. Modern linguistic theorists consider this work as the beginnings of the modern approach their subject. Arnauld's next work was Port-Royal Logic which was another book of major importance. It was also strongly influenced by Descartes' Regulae and also gave a first hand account of Pascal's Méthode. This work presented a theory of ideas which remained important in philosophy courses until comparatively recent times. In 1667 Arnauld published New Elements of Geometry. This work was based on Euclid's Elements and was intended to give a new approach to teaching geometry rather than new geometrical theorems."
He was a correspondent of Gottfried Wilhelm Leibniz, and of course Pascal, who wrote the Pascal "Provincial Letters" in support of Arnauld. I enjoyed the quote about him from the Wikipedia bio: "His inexhaustible energy is best expressed by his famous reply to Nicole, who complained of feeling tired. 'Tired!' echoed Arnauld, 'when you have all eternity to rest in?"

I have not been able to find any thing in Arnauld's personal writing at this time to confirm that he was aware of or used the Pigeon-hole Principle. I have also seen a comment that there is a book by Henry (or Henrik) van Etten (pseudonym of Jean Leurechon, who coined the term thermometer) , circa 1624, which uses the method for problems involving "if there are more pages than words on any page" and various other illustrations. The writer suggests that the problem is in the French version but not the English translation. Would love to hear from someone who can confirm, and perhaps send a digital image.






The earliest known hearing aid, called an ear trumpet, was described by Belgian scientist and high school rector Jean Leurechon in his book Récréations-Mathématiues, in 1624. The book described how to make your own ear trumpet as there were no manufacturers of the device at that time.


 

On This Day in Math - September 3


If it's just turning the crank it's algebra,
but if it's got an idea in it, it's topology.

~Solomon Lefschetz

The 246th day of the year; 246 is a sphenic (wedge) composite since it is the product of three distinct prime factors, 246 = 2x3x41. (what would be the next sphenic number?)

246 is also equal to the sum  9C2 + 9C4 + 9C6 (9 choose 2,4,6)

246 = 233 + 13 (13th Fibonacci number plus 13) *Derek Orr@Derektionary

246 is the smallest number whose complete factorization contains the first four digits (and no others) 246 = 2*3*41

Algebra Fact @AlgebraFact points out that: "Tao, et all, have proved that there are infinitely many primes 246 apart." On the way to proving, hopefully, that there are an infinity of twin primes.

246 is an untouchable number, a number that can not be formed from the proper divisors of any number. Paul Erdos proved there are an infinite number of them. The early ones are 2, 5, 62, 88, 96... There are only 29 untouchable year dates, but very unevenly divided by the century groups. 5 below 100, 5 more before 200, then 12 between 200 and 300, and 8 between 300 and 400.


246 is a palindrome in base 5(1441) and base 9(303)

246 can be expressed as the sum of three (not distinct) squares. 14^2 + 5^2 + 5*2

The "aliquot sequence" of a number is the chain of results following from iterating the sum of the aliquot factors. The Chain for 246 is 258, 270, 450, 759, 393, 135, 105, 87, 33, 15, 9, 4, 3, 1, 0. *Wikipedia

See More Math Facts for every Year Day here



EVENTS


1457  Georg Peurbach observed a lunar eclipse from a site near Vienna. He measured the duration of the eclipse and then found the time of the midpoint. It was eight minutes earlier than the time predicted by the Alphonsine Tables.These tables, prepared in Toledo, Spain, for King Alfonso X, were completed in 1252. Based on Ptolemy's theory, they represented the best data available in Peurbach's time. Peurbach produced a new collection of tables of eclipse calculations in Tabulae Ecclipsium which he completed around 1459. When he observed eclipses on 3 July and 27-28 December 1460 he was able to compare the times with the predictions contained in his own tables.

image  Georg von Peuerbach: Theoricarum novarum planetarum testus, Paris 1515



1752 The dates 3 to 13 September did not exist in England in 1752 due to the conversion to the Gregorian calendar. Poor Richard’s Almanac for 1752 carried the catchy heading, “September hath XIX days.” Much of Europe made the change in 1582, and since 1600 was a leap year under the Gregorian but not the Julian calendar, England had to omit eleven days, not ten. *VFR England and the American Colonies dropped the Roman era Julian Calendar, which had become 10 days out of synchrony with the solar cycle, and adopted the Gregorian Calendar. People rioted in the streets thinking the government stole 11 days of their lives. Instituted by Pope Gregory XIII in 1582, the calendar has 365 days with an extra day every four years (the leap year) except in years divisible by 100 but not divisible by 400. Thus, the calendar year has an average length of 365.2422 days. It moved the day's date up from September 3rd to September 14th. Some other countries, including Russia, did not change until the twentieth century.*TIS


1803 John Dalton makes the first entry in his first meteorological notebook. Dalton came to his views on atomism through his interest in meteorology. The volumes contain daily meteorological observations, vol. 1 covering from 1 Apr 1803 to 20 Mar 1816.  By September 3, 1803 he made a logbook entry that day titled, “Observations on the Ultimate Particles of Bodies and their Combinations.” It was the first use of symbols to represent the elements of modern chemistry.




1806 Francois Arago and Jean-Baptiste Biot leave Paris for Spain to finish the measurement of the Paris Meridian.  Arago had been picked to head the completion of the task while a 19yr old student at the Ecole Polytechnique.  He was nominated by his professor, Dennis Poisson and appointed on Feb 2, 1805 to finish the work began by Mechain and Delambre.  *Amir D Aczel, Pendulum, pg 75-78

François Arago was sent to the municipal college of Perpignan, where he began to study mathematics in preparation for the entrance examination of the École Polytechnique. Within two years and a half he had mastered all the subjects prescribed for examination, and a great deal more, and, on going up for examination at Toulouse, he astounded his examiner by his knowledge of J.-L. Lagrange 's work. 

Towards the close of 1803, Arago entered the École Polytechnique, Paris, but apparently found the professors there incapable of imparting knowledge or maintaining discipline. The artillery service was his ambition, and in 1804, through the advice and recommendation of Siméon Poisson, he received the appointment of secretary to the Paris Observatory. He now became acquainted with Pierre-Simon Laplace, and through his influence was commissioned, with Jean-Baptiste Biot, to complete the meridian arc measurements which had been begun by J. B. J. Delambre, and interrupted since the death of P. F. A. Méchain in 1804 *WIK

Arago by Charles de Steuben, *Wik



1806 F. Nichols sends a copy of his printing of Playfair's Geometry to Thomas Jefferson.
"Sir,—
I desire you to accept a copy of Playfair’s Geometry, which I reprinted last winter.
The corrections of grammatical inaccuracies, &. mentioned in the Advertisement, occur after Book I. There are few corrections in Book I.
The book is pretty correctly printed. The principal typographical errors appear at the end of the volume.
Some improvements will be made in another edition, if indeed another edition should ever be wanted.
Playfair’s Geometry is adopted at Cambridge in Massachusetts, Newhaven in Connecticut, & in a few private places of education. I have been informed that it will be introduced into other colleges.
It is a circumstance unfriendly to the reception of a new elementary work of science, designed for the use of students, that some teachers are unwilling to introduce any book into their seminaries, which they have not read at school or college.
I am, with respect, Sir, Your obedient Servant,
F. Nichols."
Jefferson would reply with thanks on 19 Sept.  *Natl. Archives
advertising in the Apr. 7, 1795, issue of the Massachusetts Mercury as "Francis Nichols, late professor of mathematics in the new college at Manchester"; author and bookseller at Philadelphia, 1802-14; member of the American Philosophical Society; bookseller at New York City, 1817-20)*Library of Congress

I have a copy of John Playfairs Geometry printed in 1804 in Edinburgh by Bell & Bradfute.  It was signed on the flyleaf by James Norgate, Caius College Cambridge in 1604.  On the inside of the cover it is signed by Pro James Boyst.  Below his signature is written, "Nov 7, 1946, Lord Plimton (unclear) bought this book off Plummer the Carpenter who bought it at the Boyst sale."  




1821 A Hurricane made landfall on this day in New York City and moved north into Connecticut. It would confuse and inspire William Redfield, and become the first hurricane tracked from beginning to end. While reviewing the storm damage on horseback across Connecticut Redfield noticed that trees in the northern parts of the state fell in the opposite direction from those he had witnessed further south. His interest led him to make a careful study of newspaper reports, letters and ships log an document the storm from beginning to end. He concluded, "This storm was exhibited in the form of a great whirlwind." Redfield was the first to give evidence to support that hurricanes are large circular vortexes. His study of this and other storms led to the classic meteorology paper, "On The Prevailing Storms of the Atlantic Coast." John Farrar, Professor of Mathematics and Natural Philosophy at Harvard University between 1807 and 1836, had made similar observations describing the hurricanes as “a moving vortex and not the rushing forward of a great body of the atmosphere”, after the Great September Gale of 1815..*Wik



1822 A wagon train containing three tons of books arrived at Allegheny College in Meadville, PA. They came from one of the finest private libraries in America, that of James Winthrop. He was a descendant of John Winthrop, first governor of the Massachussettts Bay Colony. His father was Professor of Mathematics and Natural Philosophy at Harvard and so the collection contained a number of important mathematical works. Winthrop was upset that Harvard had not given him an honorary degree and so he gave the books to Allegheny. [Allegheney College Alumni Bulletin, June 1933.] *VFR

It was, in a sense, Allegheny’s first capital campaign, and our first transformative gift. And it put Allegheny on the national map. Allegheny’s first President, Timothy Alden, in 1824 received an unsolicited letter, congratulating the College on its “good fortune of having become the objects of donations so liberal.”

“I had not expected there was such a private collection in the U.S.,” the author wrote. “We are just commencing the establishment of a University in Virginia but cannot flatter ourselves with the hope of such donations as have been bestowed on you.”

The letter was written by former President Thomas Jefferson. Dated Feb. 14, 1824, and penned from Monticello, the letter remains in the Pelletier Library Archives today.



1970  A record hailstone fell on Coffeyville, Kansas, the heaviest authenticated one to fall in the U.S. in the 20th century. Its weight was recorded as 1-lb 11-oz (0.77 kg) with 5.7-in (14.7 cm) diam. It broke the old record from 6 Jul 1928 at Potter, Nebraska, for one weighing about 1-lb 8-oz (0.68 kg), around 7-in diam. A newer U.S. record for size was set on 22 Jun 2003 in Aurora, Nebraska, when a hailstone was found about 7-in diam. (17.8 cm) and 18.75-in (46.6 cm) circumference. The world record was broken on 23 Jul 2010, by a hailstone found in Vivian, South Dakota at 1-lb 15-oz, (0.88 kg), 8.0-in (20 cm) diam., 18.6-in (47.3 cm) circumference. A larger hailstone is said to have fallen on 14 Apr 1986 that weighed 2-lb 4-oz (1.02 kg) during a hailstorm in Bangladesh that killed 92 people. (This might be more correctly referred to as a Hell Stone)


Later the record volume was broken.  According to the National Oceanic and Atmospheric Administration, a hailstone fell in Aurora, Nebraska, on June 22, 2003, which had a diameter of 7 inches and circumference of 18.75 inches. This hailstone, however, only weighed 1.3 pounds.




In 2000, NASA data showed the hole at just under 11 million square miles - the biggest it had ever been. Record low temperatures in the stratosphere are believed to have helped the expansion of the ozone hole during the southern hemisphere’s spring season. Antarctic ozone depletion starts in July, when sunlight triggers chemical reactions in cold air trapped over the South Pole during the Antarctic winter. It intensifies during August and September before tailing off as temperatures rise in late November of early December. Depletion of the ozone layer over Antarctica and the Arctic is being monitored because ozone protects Earth from harmful ultraviolet radiation. By 9 Sep 2000, the hole had grown over Chile, exposing a populated city for the first time. Image, compiled from NASA's Total Ozone Mapping Spectrometer instrument onboard the Earth Probe satellite, reveals how the ozone hole (in deep blue) has extended as far as southern Chile. *TIS


2009 Saturn's rings cross the plane of the Earth's orbit. This was the first such crossing since May 22, 1995, and another will not occur until March 23, 2025. *Wik

This sequence of images from the Hubble telescope documents a rare astronomical alignment: Saturn's magnificent ring system turned edge-on. This event occurs when the Earth passes through Saturn's ring plane, as it does about every 15 years.




BIRTHS


1780 Heinrich Christian Schumacher (September 3, 1780 – December 28, 1850)
Schumacher was a German astronomer. He was director of the Mannheim observatory from 1813 to 1815, and then became professor of astronomy in Copenhagen. From 1817 he directed the triangulation of Holstein, to which a few years later was added a complete geodetic survey of Denmark (finished after his death). For the sake of the survey an observatory was established at Altona, and Schumacher resided there permanently, chiefly occupied with the publication of Ephemerides (11 parts, 1822–1832) and of the journal Astronomische Nachrichten (founded by himself in 1821 and still being published), of which he edited thirty-one volumes. *TIA




1814 James Joseph,(Sylvester) (3 Sep 1814; 15 Mar 1897) youngest child of Abraham Joseph, born in London. The eldest son, an actuary, eventually migrated to the U.S. where, for unknown reasons, he took the surname Sylvester. The rest of the family soon followed suit, so that is how James Joseph Sylvester got his name. *VFR British mathematician who, with Arthur Cayley, founded the theory of algebraic invariants, algebraic-equation coefficients that are unaltered when the coordinate axes are translated or rotated. Beginning in 1833, he studied at St John's College, Cambridge. However, at this time signing a religious oath to the Church of England was required to graduate. Being Jewish, he refused and so he did not graduate. He taught physics at the University of London (1838-41), one of the few places which did not bar him because of his religion. Sylvester did important work on matrix theory, in particular, to study higher dimensional geometry. In 1851 he discovered the discriminant of a cubic equation. Earlier in his life, he tutored Florence Nightingale.*TIS (This idea of Sylvester tutoring Nightingale, to the best of my knowledge, originates from the Herbert Baker obituary. Karen Hunger Parshall, among others, has questioned the accuracy of this statement.)
He was instrumental in shaping graduate study and American mathematics in the later half of the 19th century as a professor at the Johns Hopkins University and as founder of the American Journal of Mathematics. *Wik
James Joseph Sylvester died, at age 83, after earlier suffering a paralytic stroke while working at his mathematics. *VFR
I came across a nice story about Sylvester on the wonderful "Cut-the-Knot" blog of Alexander Bogomolny. He writes, "Sylvester was one the greatest British mathematicians of the 19th century. He was known for his absentmindedness and poor memory; on one occasion he even denied the truth of one of his own theorems. "

In his youth his family was proud of the brilliant student.  While he was a teenager, his oldest brother, already in America, Aware that a group of Lottery contractors struggling with a difficult problem in combinations he suggested they contact his teenage brother James.  They did, and found his answer so complete that they paid him 500 dollars for his work.  





1869 Austrian chemist Fritz Pregl (3 September 1869 – 13 December 1930) Pegl began research on bile acids in 1904. With only tiny yields to study, he pioneered micro analytical techniques and designed a new balance capable of weighing 20 grams to an accuracy of 0.001 milligrams. Pregl was awarded the Nobel Prize in Chemistry 1923 for his efforts *RSC.org
In 1950, the department of the University of Graz where Fritz Pregl had worked was named the Institute of Medical Chemistry and Pregl Laboratory. Streets in Graz, Innsbruck, Vienna and Klagenfurt were named after him. In Slovenia, Pregl Awards have been bestowed annually since 2007 by the National Institute of Chemistry for the research work and for outstanding doctorates. Slovenian pupils are conferred Pregl Recognition Awards, whereas secondary school students are conferred Pregl Citations for excellent results in national competitions in chemistry. A square in Ljubljana is named after Pregl. The Fritz Pregl Prize has been awarded annually since 1931 in chemistry by the Austrian Academy of Sciences from the funds left at its disposal by Pregl. *Wik



1874 Fredrik (Carl Mülertz) Størmer (3 Sep 1874; died 13 Aug 1957) was a geophysicist and mathematician who developed a mathematical theory of auroral phenomena. An aurora is the light emitted by energetic protons and electrons at the top of Earth's atmosphere when they come in contact with solar wind particles. He also contributed both important photographic observations and mathematical data to the understanding of the polar aurora, of stratospheric and mesospheric clouds, and of the structure of the ionosphere. The discovery of the Van Allen Radiation Belts by James Van Allen confirmed with surprising accuracy Størmer's theoretical analysis of solar charged particle trajectories in Earth's magnetic field.*TIS



1883 Harold DeForest Arnold (September 3, 1883 – July 10, 1933) was an electronics engineer and pioneer of radio communication and telephony. He served as the first director of research at Bell Telephone Laboratories from 1925 to his death.
He initially studied under Albert A. Michelson but when he confided to Robert Andrews Millikan that he would probably have to commit suicide as he could not meet Michelson's requirement, Millikan took Arnold over as his own student. When Frank B. Jewett was looking for someone to work on repeaters for transcontinental telephony, Arnold was suggested by Millikan. Arnold worked at the University of Chicago from 1907 to 1909 and served as a professor at Mount Allison University, from 1909 to 1910 and then at University of Chicago (1910). In 1911 he joined the Western Electric Company under Edwin H. Colpitts. His earliest work was in the development of a vacuum-tube based amplifiers beginning with improvements to Lee De Forest's triode “audion”. He worked on innovations that made it possible to demonstrate the first radio transmission between Arlington, Virginia, and Paris, France, in October 1915. During World War I he served as a captain in the signal corps. He developed and refined manufacturing techniques for vacuum tubes, oxide coatings for filaments, and other innovations for reliability and ease of replacement. Permalloy and Perminvar were developed by his team and this helped improve signal quality in undersea cables. Arnold received the John Scott Medal in 1928 *Wik




1884 Solomon Lefshetz (3 September 1884 – 5 October 1972) born in Moscow. He invented the phrase “algebraic topology.” See A Century of Mathematics in America, Part I, 1988, p. 171. *VFR mathematician who did fundamental work on algebraic topology, its applications to algebraic geometry, and the theory of non-linear ordinary differential equations.*Wik



1905 Carl David Anderson (3 Sep 1905; 11 Jan 1991)American physicist who, with Victor Francis Hess of Austria, won the Nobel Prize for Physics in 1936 for his discovery of the positron, or positive electron, the first known particle of antimatter. He examined the photographs of cosmic rays taken as they passed through a Wilson cloud chamber in a strong magnetic field. Besides the curved paths of negative electrons, he found also paths deviating in the opposite direction, corresponding to positively charged particles - yet having the the same mass as an electron! Previously, Dirac had predicted such particles by theoretical solution to electromagnetic field equations. *TIS



*wik



1908 Lev Semenovich Pontryagin (3 September 1908 – 3 May 1988) One of the 23 problems posed by Hilbert in 1900 was to prove his conjecture that any locally Euclidean topological group can be given the structure of an analytic manifold so as to become a Lie group. This became known as Hilbert's Fifth Problem. In 1929 von Neumann, using integration on general compact groups which he had introduced, was able to solve Hilbert's Fifth Problem for compact groups. In 1934 Pontryagin was able to prove Hilbert's Fifth Problem for abelian groups using the theory of characters on locally compact abelian groups which he had introduced. *SAU [He was buried at the Novodevichie Memorial Cemetery in Moscow.]
Alexandre Zagoskin commented, "Lev Pontryagin completely lost his sight at the age of 14 due to an accident and was then helped by his schoolmates and his mother, who read to him the textbooks. His mother learned German to read him research papers when he studied at the university."   




1970 Stanislav Konstantinovich Smirnov (3 September 1970 - ) is a Russian mathematician currently working at the University of Geneva, who was awarded the Fields Medal in 2010. His research focuses on the fields of complex analysis, dynamical systems and probability theory. *Wik





DEATHS


1595 Federico Commandino (1509 – September 5, 1575) died on this day. “In the sixteenth century, Western mathematics emerged swiftly from a millennial decline. This rapid ascent was assisted by Apollonius, Archimedes, Aristarchus, Euclid, Eutocius, Hero, Pappus, Ptolemy, and Serenus—as published by Commandino,” *VFR He translated the works of ancient mathematicians and was responsible for the publication of the works of Archimedes. He also translated the works of Aristarchus of Samos (On the masses and distances of the Sun and the Moon), Pappus of Alexandria (Mathematical collection), Hero of Alexandria (Pneumatics), and Euclid (Elements). Among his pupils was Guidobaldo del Monte. Commandino maintained a correspondence with the astronomer Francesco Maurolico.
The proposition known as Commandino's theorem** first appears in his work on centers of gravity, Liber de centro gravitatis solidorum in 1565. *Wik
**The four medians of a tetrahedron concur in a point which divides each tetrahedron median in the ratio 1:3, the longer segment being on the side of the vertex of the tetrahedron. Student's should compare this to the property of the medians of a triangle which concur at a point that divides the median in a 1:2 ratio.




1894 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




1910 Wilhelm Winkler (29 June 1884 in Prague, Bohemia (Austro-Hungarian Empire, now Czech Republic - 3 Sept 1984 in Vienna, Austria) After attending the trading high school in Gera, Winkler worked as a merchant in Eisenberg, following in the footsteps of his grandfather. In 1875 he gave up this trade and devoted his time entirely to astronomy. Advised by Carl Bruhns, director of the Leipzig University Observatory, he established an observatory on his estate in Gohlis near Leipzig. From 1878 Winkler regularly observed sunspots; other fields of his observational interests were comets, occultations of stars by the Moon, and Jupiter's satellites. *Uni Bonn Web page




1967 William P Milne (22 May 1881 in Longside, Aberdeenshire, Scotland - 3 Sept 1967 in Glack, Aberdeenshire, Scotland) studied at Aberdeen and Cambridge universities. He taught at Clifton College and then became Professor of Mathematics at Leeds. He published papers in Geometry including many in the Proceedings of the EMS. *SAU (Not to be confused with the William J Milne who, as President of the New York State Normal School in Albany, wrote many popular textbooks in arithmetic, algebra and geometry for high school use)



1992 Barbara McClintock (16 Jun 1902, 3 Sep 1992) American scientist regarded as one of the most important figures in the history of genetics. In the 1940s and 1950s McClintock's work on the cytogenetics of maize led her to theorize that genes are transposable - they can move around - on and between chromosomes. McClintock drew this inference by observing changing patterns of coloration in maize kernels over generations of controlled crosses. The idea that genes could move did not seem to fit with what was then known about genes, but improved molecular techniques of the late 1970s and early 1980s allowed other scientists to confirm her discovery. She was awarded the 1983 Nobel Prize in Physiology or Medicine, the first American woman to win an unshared Nobel Prize. *TIS

*Wik



1995 Bent Christiansen (7 May, 1921 - 3 Sept, 1996)  From his Obituary: "Bent was a legend in mathematics education in Denmark and the Nordic countries. His impact on the development of the teaching and learning of mathematics in primary and lower secondary education can hardly be over-estimated. He wrote textbooks and books on mathematics education, especially the very influential 'Goals and means in basic mathematics education' ('Mål og midler I den elementære matematikundervisning', 1967). He gave innumerable in-service courses and invited lectures at meetings and conferences. Naturally, he also served on hosts of national committees, including the Danish National Sub-Commission of ICMI (1961-1972). All this earned him a reputation as a charismatic, enthusiastic and extremely energetic mentor for generations of mathematics teachers, teacher trainers and colleagues."




2016  Jean-Christophe Yoccoz (May 29, 1957, September 3, 2016)  is a French mathematician , born on in Paris where he also died . He was awarded theFields Medalin 1994, and then became a professor at the Collège de Francein 1996. He is particularly known for his work on dynamical systems.


Jean-Christophe Yoccoz is the son of a physicist , Jean Yoccoz, appointed director of the CNRS's National Institute of Nuclear and Particle Physics in 1975 


Upon graduating from the ENS in 1979, he was appointed research fellow and then CNRS research fellow at the École Polytechnique , a position he held until 1988  . During this period, in the early 1980s , he completed his national service in cooperation with the Instituto de Matematica Pura e Aplicada in Rio de Janeiro . He defended his doctoral thesis at Paris-XI University in 1985 under the supervision of Michaël Herman of the Centre de mathématiques de l'École Polytechnique, before being awarded the Salem Prize in 1988. A strong chess player, he notably participated in the French Chess Championship in 1980  .

He was a professor at Paris-Sud University from 1988 to 1996  . He became a member of the Institut Universitaire de France in 1991  . He was awarded the Fields Medal in 1994 at the International Congress of Mathematicians in Zurich  for his work on the theory of dynamical systems . He was elected a member of the French Academy of Sciences on October 24, 1994, in the "  Mathematics  " section. He was also a member of the Brazilian Academy of Sciences . He was a professor at the Collège de France from 1996, holding the chair of differential equations and dynamical systems. From 2012 to 2016, he was a member of the board of directors of the Hugot Foundation at the Collège de France . He was part of the Bourbaki group . He died onSeptember 3, 2016following a long illness. His colleague and friend Pierre-Louis Lions , who had also received the Fields Medal in 1994, said of him upon hearing of his death   : "  He had a great speed of thought and analysis, was capable of flashes of brilliance.  

His work focuses primarily on dynamical systems. His study aims to "  understand the behavior of anything that can move, like the planets around the Sun  " . In this exploration of the boundary between chaos and regularity, Jean-Christophe Yoccoz has, for example, constructed tools, called "  Yoccoz puzzles  ," which allow spaces to be divided into small pieces in order to study them without losing sight of the whole  . He has thus "  significantly advanced the study of Mandelbrot fractals . *Wik 





2021  David Borwein (March 24, 1924 – September 3, 2021) was a Lithuanian-born Canadian mathematician, known for his research in the summability theory of series and integrals. He also did work in measure theory and probability theory, number theory, and approximate subgradients and coderivatives. He latterly collaborated with his son, Jonathan Borwein, and with B.A. Mares Jr. on the properties of single-variable and many-variable sinc integrals.

He formerly resided and worked in St. Andrews, Scotland, before moving to London, Ontario where he eventually became Head of Mathematics at the University of Western Ontario. He was also the president of the Canadian Mathematical Society (CMS). The David Borwein Distinguished Career Award given out by the CMS is named after him. He was an active researcher in summability theory, classical analysis, inequalities, matrix transformations, and was professor emeritus at the University of Western Ontario, department of Mathematics.

His wife of over 60 years, Bessie Borwein, is a prominent anatomist, and is professor emerita of anatomy at the University of Western Ontario.

In 2018 the Canadian Mathematical Society listed him in their inaugural class of fellows.

Borwein died in his sleep on September 3, 2021, at the age of 97.




247 = 50123 - 49876


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