Sunday, 13 September 2026

On This Day in Math - September 14

 



Mathematicians have tried in vain to this day to discover some order in the sequence of prime numbers, and we have reason to believe that it is a mystery into which the human mind will never penetrate.
~Leonhard Euler


The 257th day of the year; 257 is a prime number of the form 223+1 and therefore a Fermat prime. It is currently the second largest known Fermat prime.

257 is the third consecutive number (255,256,257) for which the regular n-gon is constructible with straightedge and compass. The 255th day of the year; 255= 28-1 is the product of three distinct Fermat Primes, 3*5*17, 256=28 is a power of two, and 257 is a Fermat Prime *HT to Don S. McDonald ‏@McDONewt  (Goldbach used the fact that all Fermat Numbers are 2 + product of all smaller Fermat Primes to prove that no two Fermat Numbers share a common prime divisor)

257 = 44 + 1 It is the largest known prime of the form nn + 1. *Prime Curios

More than 90% of all positive integers are composite numbers that have a lowest prime factor of 257 or less.

2257 - 1 is the largest number in Mersenne's list of primes in the preface to his Cogitata Physica-Mathematica (1644), it later turned out to be Composite. * Dan Garbowitz ‏@DGoneseventh

Ones and zeros, 257 written in different bases, 1000000012, 100014   10116





EVENTS


In 1716, Boston Light, the first lighthouse in America was first lighted just before sunset. Located on Little Brewster Island to mark the entrance to Boston, Massachusetts, harbour, has guided ships since then. Building it was authorized 23 Jul 1715 by the Boston Light Bill. In the 1600s, treacherous rocks caused countless loss of lives. False signal fires lit in the wrong places by “wreckers” lured ships aground to plunder. Boston Light was blown up by the British in 1776, but rebuilt in 1783 by Governor John Hancock. The lighthouse is also the last remaining manned station in the U.S.




1752 The first day of the Gregorian calendar in Britain and its colonies. 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.” Benjamin Franklin wrote 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. The Act also rectified other dating anomalies, such as changing the start of the legal year from 25 March to 1 January (except in Scotland where they had changed the New Year to Jan 1 in 1600.)  

Benjamin Franklin, who was then 46, didn't think about losing 10 days. He looked on the bright side, and advised his readers to do the same. He gave the following advice to readers of his newspaper, Poor Richard's Almanac: Do not to look upon the loss of 10 days with wonder or scorn. Do not regret the removal of 10 days from the calendar. All those who love sleep can console themselves by thinking about how wonderful it will be to go to bed on the second of the month and to sleep until the morning of the 14th.
 
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
In 1755 William Hogarth’s satirical print, “An Election Entertainment,” was published. It contains a Tory sign bearing the inscription “Give us our eleven days.” (out the window).  Despite thousands of tales of ignorant peasants protests and riots, there seems to be no true records of such an event. Historian Robert Poole  has written, "the riots, like the Snarks, are universally known, but defy detection."

*HT toGianluca Spizzo who noted: "… two centuries later!
Voltaire wrote on this his famous wit, that Protestants preferred to disagree with the Sun than agree with the Pope… "





1792 
In a letter from Bernardino Ferrari to Sebastiano Canterzani describes the interest created by Galvani's "Frog" experiment. Writing from Milan he said "Now here the experiments are also repeated in ladies’ salons, and they furnish a good spectacle to all. " *Walter Bernardi, The Controversy on Animal Electricity (web post)




1814 Francis Scott Key wrote “The Star-Spangled Banner.” Actually he wrote a poem called "Defence of Fort McHenry" . The Poem was written by the 35-year-old lawyer and amateur poet after witnessing the bombardment of Fort McHenry by the British Royal Navy ships in Chesapeake Bay during the Battle of Fort McHenry in the War of 1812. The tune was actually a popular British tune written for a mens social club in London which had become popular in the US too. It became the official National Anthem on March 3, 1931 when President Hoover signed a Congressional resolution to that effect. Mathematics??? umm, OK, the song has a range of 1 1/2 octaves, so the highest note has a frequency that is the square root of eight times the lowest note. *wik (by the way all you patriotic types, sing the second verse)


Fort Meade, near Sturgis, South Dakota is often called the “birthplace” of the national anthem.   In 1892  Colonel Caleb H. Carlton, commander of the 8th Cavalry at Fort Meade, decided that the United States ought to have a national song that would be treated with the dignity accorded to national anthems in other countries.

According to Carlton's later account, he and his wife had discussed the subject. His wife, Sadie Carlton, suggested The Star-Spangled Banner. Carlton agreed because of the extraordinary circumstances under which Francis Scott Key had written it in 1814 and because of its association with the American flag.
 Carlton then ordered that The Star-Spangled Banner be played at the daily retreat ceremony, when the flag was lowered, and required those present to stand and show respect. He also had it played at parades and concerts. 
Carlton didn't simply establish the practice at Fort Meade and leave it there.
He actively promoted the idea elsewhere. He told visiting South Dakota Governor Charles Sheldon about the custom. He subsequently discussed it with Pennsylvania officials and, most importantly, communicated with Secretary of War Daniel S. Lamont.
Carlton later recalled that Lamont subsequently issued an order requiring "The Star-Spangled Banner" to be played at every Army post at evening retreat.*HT to Dr David M Grabitske for giving me the note about Ft Mead.




1858 
 The Donati Comet was first seen and named after its discoverer, Giovanni Battista Donati, at Florence earlier in the year. It was the second-brightest comet of the nineteenth century It reached perihelion on 30 Sep 1858.  On Sep 14th, the night before his third debate with Stephen Douglas, Abraham Lincoln sat on the porch of the Jonesboro, Illinois hotel and viewed the comet with a friend.  On Sept. 27,  It became the first comet to be photographed. The English photographer Warren De La Rue captured the comet on a collodion plate using a telescope at the Royal Observatory, Greenwich.


1959 Bank of America accepts the ERMA (Electronic Recording Method of Accounting) system. This revolutionary system digitized checking for the Bank of America by creating a computer-readable font. A special scanner read account numbers preprinted on checks in magnetic ink. The system was developed at the Stanford Research Institute in Menlo Park, California.*CHM
An early check, demonstrating the features developed by SRI: account numbers and Magnetic Ink Character Recognition.



1959 Life Magazine cover story is picture of the first seven Nasa Astronauts.


2015 Einstein was right, when large Gravitational events happen in space, they produce a gravitational wave pulsing through the universe at the speed of light. The Laser Interferometer Gravitational-Wave Observatories (LIGO) recorded the first evidence on this date of a gravitational wave which had resulted from a merging of a pair of black holes each of about 30 solar masses which had merged about 1.3 billion light years ago. As of December of 2018, LIGO has recorded eleven gravitational wave events, ten from mergers of black holes, and one from a collision of two neutron stars. *Wik, *The Perfectionists, Simon Winchester.





BIRTHS


1648 Caspar (or Kaspar) Neumann (14 September 1648 – 27 January 1715) was a German professor and clergyman from Breslau with a special interest in mortality rates. His collection and publication of the births and deaths in Breslaw were the foundation of E. Halley's, An Estimate of the Degrees of the Mortality of Mankind, drawn from curious Tables of the Births and Funerals at the City of Breslaw; with an Attempt to ascertain the Price of Annuities upon Lives presented to the Royal Society. Halley noted that no similar records existed of sufficient quantity in an area where the population was stable.
He first did an apprenticeship as a pharmacist. He finished his higher school education at Breslau's Maria-Magdalen grammar school. In 1667 he became a student of theology at the university of Jena, and on Nov. 30, 1673 was ordained as a priest, having been requested as a traveling chaplain for Prince Christian, the son of Ernest I, Duke of Saxe-Gotha. On his return home, following a two-year journey through west­ern Ger­ma­ny, Switz­er­land, north­ern It­a­ly, and south­ern France, he became a court-chaplain at Altenburg, and married the daughter of J. J. Rabe, physician in ordinary to the prince of Saxe-Friedenstein. In 1678 he was made the deacon of St. Maria-Magdalen in Breslau and became pastor in 1689. *Wik He was a student of Erhard Weigel



1713 Johann Kies (September 14, 1713—July 29, 1781) a German astronomer and mathematician. Born in Tübingen, Kies worked in Berlin in 1751 alongside Jérôme Lalande in order to make observations on the lunar parallax in concert with those of Nicolas Louis de Lacaille at the Cape of Good Hope.
From 1742 to 1754, at the recommendation of the mathematician Leonhard Euler, he was made professor of mathematics at Berlin's Academy of Sciences and astronomer at its observatory.
He subsequently taught also at the Collegium of Tübingen. From 1754 to 1755, Kies served as director of the Astronomisches Rechen-Institut in Heidelberg.
Kies was one of the first to propagate Newton's discoveries in Germany, and dedicated two of his works to the Englishman: De viribus centralibus (Tübingen, 1758) and De lege gravitatis (Tübingen, 1773). Kies is also the author of a work on lunar influences: De influxu lunae in partes terrae mobiles (Tübingen, 1769). He wrote many other works, both in French and in Latin, on astronomy.
Kies corresponded with Euler from 1747 to 1767. Their correspondence consists of 8 letters, all of which were written by Kies.
The crater Kies on the Moon is named in his honor. *TIA



1769 (Baron) Friedrich Wilhelm Heinrich Alexander von Humboldt (14 Sep 1769; 6 May 1859) was a German natural scientist, archeologist, explorer and geographer, who made two major expeditions to Latin America (1799-1804) and to Asia (1829). During the first, equipped with the best scientific instruments, he surveyed and collected geological, zoological, botanical, and ethnographic specimens, including over 60,000 rare or new tropical plants. He charted and made observations on a cold ocean current along the Peruvian coast, now named, the Humboldt Current. In geology, he made pioneering observations of stratigraphy, structure and geomorphology; he understood the connections between volcanism and earthquakes. Humboldt named the Jurassic System. *TIS
Basalt prisms at Santa María Regla, Mexico by Alexander von Humboldt, *Wik 




1837 Nicolai Vasilievich Bugaev (14 Sept 1837 , 11 June 1903) His research was mainly on analysis and number theory. Bugaev gave proofs of theorems stated without proof by Liouville. He wrote on algebraic integrals of certain differential equations. His work in Moscow was to lead to the creation of the Moscow school of the theory of functions of a real variable in 1911, eight years after his death by Egorov, one of his students. Sonin was another of Bugaev's pupils who went on to make a major contribution to mathematics.
Bugaev's most important work in number theory was based on an analogy between some operations in number theory and the operations such as differentiation and integration in analysis. Bugaev built a systematic theory of discontinuous functions which he called arithmology. *SAU



1858 Henry Burchard Fine (September 14, 1858 – December 22, 1928) born in Chambersburg, Pennsylvania. Fine began his time as a Princeton undergraduate studying Greek and Latin, but a mathematics tutor, George B. Halstead, convinced him to switch his considerable talents to mathematics. He ranked highest academically in his Class of 1880 for all four years, during which he caught the attention of President James McCosh. As a result, Fine was among a small group of highly talented undergraduates whom McCosh invited to his house for informal seminars and nurtured as future faculty.

After graduation, Fine remained at Princeton (then called the College of New Jersey) for a year of post-graduate work followed by three more years as a tutor. Then, as Germany was the leading center of mathematics scholarship, he went to the University of Leipzig to study mathematics with Felix Klein under whom he earned his PhD in one year.The mathematics building at Princeton is named in his honor. (Fine Hall is the tallest building on the campus)







1887 Karl Taylor Compton (14 Sep 1887; 22 Jun 1954) American educator and physicist who directed development of radar during WW II. His research included the passage of photoelectrons through metals, ionization and the motion of electrons in gases, fluorescence, the theory of the electric arc, and collisions of electrons and atoms. In 1933, President Roosevelt asked him to chair the new Scientific Advisory Board. When the National Defense Research Committee was formed in 1940, he was chief of Division D (detection: radar, fire control, etc.) In 1941, he was in charge of those divisions concerned with radar within the new Office of Scientific Research and Development (OSRD). Afterwards he was cited for personally shortening the duration of the war. (Brother of Arthur H. Compton, American Physicist and Nobel Laureate.)*TIS In the famous photo of physicists in the Solvay Conference, Compton is one of only two Americans Present.
He was president of the Massachusetts Institute of Technology (MIT) from 1930 to 1948.




1891 Ivan Matveevich Vinogradov (14 Sept 1891 , 20 March 1983) Vinogradov used trigonometric series to attack deep problems in analytic number theory.
In analytic number theory, Vinogradov's method refers to his main problem-solving technique, applied to central questions involving the estimation of exponential sums. In its most basic form, it is used to estimate sums over prime numbers, or Weyl sums. It is a reduction from a complicated sum to a number of smaller sums which are then simplified. He also used this technique on the Dirichlet divisor problem, allowing him to estimate the number of integer points under an arbitrary curve. This was an improvement on the work of Georgy Voronoy.

In 1918 Vinogradov proved the Pólya–Vinogradov inequality for character sums.
Vinogradov served as director of the Mathematical Institute for 49 years. For his long service he was twice awarded the order of The Hero of the Socialist Labour. The house where he was born was converted into his memorial – a unique honour among Russian mathematicians. As the head of a leading mathematical institute, Vinogradov enjoyed significant influence in the Academy of Sciences and was regarded as an informal leader of Soviet mathematicians, not always in a positive way: his anti-Semitic feelings led him to hinder the careers of many prominent Soviet mathematicians. *Wik




1906 Franz Rellich (September 14, 1906–September 25, 1955) was an Austrian-Italian mathematician. He made important contributions in mathematical physics, in particular for the foundations of quantum mechanics and for the theory of partial differential equations
Among Rellich's most important mathematical contributions are his work in the perturbation theory of linear operators on Hilbert spaces. Although the origins and applications of the problem are in quantum mechanics, Rellich's approach was completely abstract.

Rellich successfully worked on many partial differential equations with degeneracies. For instance, he showed that in the elliptic case, the Monge-Ampère differential equation, while not necessarily uniquely soluble, can have at most two solutions.

Particularly relevant to physics was Rellich's mathematical clarification of the outgoing Sommerfeld conditions.
.*Wik 




1914 Robert Sinclair Dietz (14 Sep 1914; 19 May 1995) was an American geophysicist and oceanographer who set forth a theory (1961) of seafloor spreading (a term he coined), in which new crustal material continually upswells from the Earth's depths along the mid-ocean ridges and spreads outward at a rate of several inches per year. While a student Dietz identified the Kentland structure in Indiana as a meteoric impact site. His professors steered him toward marine geology. He became the founder and director of the Sea Floor Studies Section at the Naval Electronics Laboratory (1946-1963). He also achieved prominence by studying meteorite craters, both on Earth and on the moon and arguing that these impact craters were common. He died of a heart attack.*TIS
 While at the Scripps Institution of Oceanography he observed the nature of the Emperor chain of seamounts that extended from the northwest end of the Hawaiian Island–Midway chain and speculated over lunch with Robert Fisher in 1953 that something must be carrying these old volcanic mountains northward like a conveyor belt.  





1920 Alberto Pedro Calderón (September 14, 1920- April 16, 1998) was one of the leading mathematicians of the 20th century. He was born in Mendoza, Argentina. His name is associated with the University of Buenos Aires, but first and foremost with the University of Chicago, where Calderón and his mentor, the distinguished analyst Antoni Zygmund, started one of the longest (more than 30 years) and most productive collaborations in mathematical history. Together they developed the ground-breaking theory of singular integral operators, thus creating the "Chicago School of (hard) Analysis" (sometimes simply known as the "Calderón-Zygmund School"); this has been one of the most influential movements in pure mathematics, but with remarkable applications to science and engineering as well. Calderón’s work, characterized by great originality, elegance and power reshaped the landscape of mathematical analysis and ranged over a wide variety of topics: from singular integral operators to partial differential equations, from interpolation theory to Cauchy integrals on Lipschitz curves, from ergodic theory to inverse problems in electrical prospection. Calderón’s work has also had a powerful impact on practical applications including signal processing, geophysics, and tomography. *Wik



1926 Hans-Joachim Bremermann​ (14 September, 1926 - 21 February, 1996) was a German-American mathematician and biophysicist. He worked on computer science and evolution, introducing new ideas of how mating generates new gene combinations. Bremermann's limit, named after him, is the maximum computational speed of a self-contained system in the material universe.
 Bremermann's limit, named after him, is the maximum computational speed of a self-contained system in the material universe.
Bremermann came to the United States in 1952 and held a research associate position at Stanford University. In 1953, he was appointed a research fellow at Harvard University. He returned to Münster for 1954–55.

After returning to the United States, he was a mathematics researcher at the Institute for Advanced Study in Princeton (1955–57), and then appointed assistant professor at the University of Washington, Seattle (1957–58). He then spent another year researching at Princeton (1958–59), this time in physics.

In 1959, he became an associate professor of mathematics at University of California, Berkeley, where he remained for the rest of his career, being promoted to full professor in 1966. He held chairs at Berkeley in mathematics and biophysics. By the 1960s, his work had turned towards the theory of computation and evolutionary biology, in which he studied complexity theory, genetic search algorithms, and pattern recognition.

In 1978 he gave the "What Physicists Do" series of lectures at Sonoma State University, discussing physical limitations to mathematical understanding of physical and biological systems. He continued work in mathematical biology through the 1980s, developing mathematical models of parasites and disease, neural networks, and AIDS epidemiology and pathology. He retired from the University of California in 1991.*Wik



1936 Leone Minna Burton (née Gold; 14 September 1936 – 1 December 2007) was a professor of education in mathematics and science, working in London teacher education colleges in the 1970s, the Open University in the 1980s and, from 1992, the University of Birmingham. At the South Bank Polytechnic (now London South Bank University), she helped establish the first MSc in Mathematics Education in the UK. After retiring in 2001 she became Honorary Professor at King's College London, and Visiting Fellow in the Cambridge University Faculty of Education. She was noted for her influence as a researcher and doctoral supervisor, setting up national and international research networks in the developing area of mathematics education.
Leone Burton's contribution to mathematics education focused on researching the practices of working mathematicians and arguing their relevance for school teaching and learning. This research is included in what is now termed the field of ethnomathematics which examines how mathematics is related to the culture in which it is developed. At the Open University, Burton collaborated in creating innovative courses in teacher education, Developing Mathematical Thinking, that emphasized the role of problem solving in mathematics and argued that teachers should be aware of mathematical reasoning as well as mathematical content. A subsequent publication, Thinking Mathematically, written in 1982 with Mason and Stacey, brought these ideas to an international teacher audience focusing on teachers' own knowledge of using and applying mathematics.

From 1984 to 1988 Burton was international convenor for the International Organization of Women and Mathematics Education and visiting professor at institutions in Asia. She played a major role in shifting teachers’ perceptions in relation to girls and mathematics in the UK and other places around the world. Burton founded the monograph series International Perspective on Mathematics Education with the Greenwood Publishing group in 2001 which published three monographs between 2002 and 2006. This monograph series was subsequently renamed International Perspectives on Mathematics Education: Cognition, Equity and Society in honor of her pioneering work on equity and gender issues in mathematics education, edited by Bharath Sriraman, and published by Information Age Publishing.

Her final book, Mathematicians as Enquirers, used interviews to characterize the ways professional mathematicians learn, including enquiry, visualization and collaboration. This research showed that the ways mathematicians learn are consistent with principles recognized in mathematics education research as suitable for school learning.






DEATHS

1638 Pierre Vernier (19 Aug 1584, 14 Sep 1638) French mathematician who developed the vernier scale, which enabled instruments to make more accurate linear or angular measurements. He first described it in a work entitled La construction, l'usage et les propriétés du cadran nouveau (1631)*. It consists of a small graduated scale or arc made to slide along a larger fixed scale or arc to enable determining the increment between two graduations of the larger scale. The ten divisions of the smaller, vernier scale are equal to nine of the fixed scale. For example, calipers with a larger scale graduated in tenths of inches can be read by use of the vernier scale to within one-hundredths of an inch. Vernier scales are also used on sextants and mercury
column barometers.*TIS
The vernier scale was invented in its modern form in 1631 by Vernier), but its use was described in detail in English in Navigatio Britannica (1750) by John Barrow, the mathematician and historian. In some languages, this device is called a nonius. It was also commonly called a nonius in English until the end of the 18th century. Nonius is the Latin name of the Portuguese astronomer and mathematician Pedro Nunes (1502–1578) who in 1542 invented a related but different system for taking fine measurements on the astrolabe (nonius) that was a precursor to the vernier. The French astronomer Jérôme Lalande (1732-1807) popularized the name of the instrument as a "vernier" in his book on astronomy (1764) *Wik

1712 Giovanni Domenico Cassini (8 Jun 1625, 14 Sep 1712) Italian-French astronomer who discovered (1675) the dark gap subdividing Saturn's rings into two parts, now known as Cassini's Division. He stated that Saturn's ring, believed by Huygens to be a single body, was actually composed of small particles. Cassini also discovered four of Saturn's moons: Iapetus (Sep 1671), Rhea (1672) and on 21 Mar 1684,* Tethys and Dione. He compiled new tables (1662) on the annual motion of the Sun. He observed shadows of four Galilean satellites on Jupiter (1664), and measured its rotation period by studying the bands and spots on its surface. He determined the period of rotation of Mars (1666), and attempted the same for Venus. His son Jacques was also an astronomer.*TIS (There were four consecutive Cassini generations to hold the post at the French Observatory. After Giovanni came Giovanni's son Jacques, then his grandson César-François Cassini de Thury, and finally his great grandson Jean-Dominique Cassini, Conte de Cassini.)
The Cassini spaceprobe, launched in 1997, was named after him and became the fourth to visit Saturn and the first to orbit the planet. It met it's end falling into the atmosphere of Saturn on the 15 September, 2017.




1835 The Rt. Rev. John Mortimer Brinkley D.D. (ca. 1763 (Baptized 31 Jan,1763, Woodbridge, Suffolk – 14 September 1835, Dublin) was the first Royal Astronomer of Ireland and later Bishop of Cloyne.
He graduated B.A. in 1788 as senior wrangler and Smith's Prizeman, was elected a fellow of the college and was awarded M.A. in 1791. He was ordained at Lincoln Cathedral in the same year, and in 1792 became the second Andrews Professor of Astronomy in the University of Dublin, which carried the new title of Royal Astronomer of Ireland. Together with John Law, Bishop of Elphin, he drafted the chapter on "Astronomy" in William Paley's Natural Theology. His main work concerned stellar astronomy and he published his Elements of Plane Astronomy in 1808. In 1822 he was elected a Foreign Honorary Member of the American Academy of Arts and Sciences. He was awarded the Copley Medal by the Royal Society in 1824. Brinkley's observations that several stars shifted their apparent place in the sky in the course of a year were disproved at Greenwich by his contemporary John Pond, the Astronomer Royal. In 1826, he was appointed Bishop of Cloyne in County Cork, a position he held for the remaining nine years of his life. Brinkley was elected President of the Royal Astronomical Society in 1831, serving in that position for two years.
He died in 1835 at Leeson Street, Dublin and was buried in Trinity College chapel. He was succeeded at Dunsink Observatory by Sir William Rowan Hamilton. *Wik



1882 Georges Leclanché  9 October 1839 – 14 September 1882 ) French engineer who invented the wet cell Leclanché battery (1866), ancestor of the familiar carbon-zinc dry cell batteries used to power portable electric lights and electronic devices. His wet cell, provided an e.m.f. of about 1.5 volts. A porous pot containing manganese dioxide and a carbon rod as current collector was immersed in an electrolyte of ammonium chloride solution with a negative terminal of zinc metal. From 1867, Leclanché gave full-time attention to his invention, which was adopted the following year by the Belgian telegraph service. He opened a factory to manufacture the battery. In 1881, J.A. Thiebaut had the idea of packing the chemicals in a zinc cup. Carl Gassner made the first commercially successful "dry" cell.*TIS




1912 Georg Landsberg (30 Jan 1865 , 14 Sept 1912) studied the theory of functions of two variables and also the theory of higher dimensional curves. In particular he studied the role of these curves in the calculus of variations and in mechanics.
He worked with ideas related to those of Weierstrass, Riemann and Heinrich Weber on theta functions and Gaussian sums. His most important work, however was his contribution to the development of the theory of algebraic functions of a single variable. Here he studied the Riemann-Roch theorem.
He was able to combine Riemann's function theoretic approach with the Italian geometric approach and with the Weierstrass arithmetical approach. His arithmetic setting of this result led eventually to the modern abstract theory of algebraic functions.
One of his most important works was Theorie der algebraischen Funktionen einer Varaiblen (Leipzig, 1902) which he wrote jointly with Kurt Hensel. This work remained the standard text on the subject for many years. *SAU



1916 Pierre-Maurice-Marie Duhem (10 Jun 1861, 14 Sep 1916) was a French physicist, philosopher of science and mathematician who emphasized a history of modern science based on evolutionary metaphysical concepts. He had a wide variety of mathematical interests from mechanics and physics to philosophy and the history of mathematics. Duhem studied magnetism following the work of Gibbs and Helmholtz and also worked on thermodynamics and hydrodynamics producing over 400 papers. He maintained that the role of theory in science is to systematize relationships rather than to interpret new phenomena.*TIS

Kai Wenz reached out and sent a link to point out one of Duhem's big contributions to thermodynamics.  My thanks to Kai for sharing, and please enjoy:   https://www.linkedin.com/posts/kai-wenz_equations-physics-thermodynamics-activity-7342461354475241472-Rrhc?utm_source=share&utm_medium=member_android&rcm=ACoAAD7cn3wBl6ENNa5xUGyD1St4HSISx-8nfLA




1925 Charles Tweedie (27 June 1868 , 14 Sept 1925) studied at Edinburgh, Göttingen and Berlin. He returned to Edinburgh as assistant to Prof. George Chrystal. In the autumn of 1892 he became an assistant in the mathematics department at the University of Edinburgh under Professor Chrystal and became an official soon after, as Chrystal's right-hand man.
He served as a Schools Inspector and published works on the History of Mathematics. He became President of the EMS in 1903 and an honorary member in 1915. *SAU



1926 Johan Ludvig Emil Dreyer (13 Feb 1852, 14 Sep 1926) Danish astronomer who compiled the New General Catalog of Nebulae and Clusters of Stars, (NGC) in 1888. When he became Director of the Armagh Observatory in 1882, financially it was destitute, with no prospect of replacing its aging instruments. Though Dreyer obtained a new 10-inch refractor by Grubb, the lack of funding for an assistant, precluded him from a continuation of traditional positional astronomy. Instead he concentrated on the compilation of observations made earlier. The NGC he listed 7840 objects and in its supplements (1895, 1908) he added a further 5386 objects. It still remains one of the standard reference catalogs.*TIS




1932 Ernest Julius Wilczynski (13 Nov 1876 , 14 Sept 1932) began his research career as a mathematical astronomer. This interest lasted until he was appointed to Berkeley. By that time he had published over a dozen papers in astronomy, but his interests moved towards differential equations which arose in his study of the dynamics of astronomical objects. From there his interests became pure mathematical interests in differential equations. However, Wilczynski's main work was in projective differential geometry and ruler surfaces. He extended Halphen's work, devised new methods and extended the theory of curves to surfaces.*SAU



1973 Eleanor Pairman Brown (8 June 1896, 14 Sept 1973) graduated from Edinburgh. She went to London where she worked with Karl Pearson and then went to the USA where she gained a doctorate from Radcliffe College ( only the third woman to receive a doctorate in math from Radcliffe College in Massachusetts )   *SAU 
Eleanor Pairman graduated with an MA in 1917 with first class honors in mathematics and natural philosophy, after which she was awarded a three-year Vans Dunlop scholarship which permitted her to continue her studies at any university. Pairman read two papers at meetings of the Edinburgh Mathematical Society early in 1918.

In 1918 Pairman joined the staff of Karl Pearson's Department of Applied Statistics, which comprised the Biometric Laboratory and Francis Galton Laboratory for National Eugenics, at University College London. Pairman's role in the Galton Laboratory was that of a human computer. She was referenced as one of a number of women contributors in the 1917 Galton Laboratory publication A study of the long bones of the English skeleton Part I, co-authored by Julia Bell and Karl Pearson and which sought to identify "racial differences in man".

In 1919, Pairman co-authored with Karl Pearson the paper "On Corrections for the Moment-Coefficients of Limited Range Frequency Distributions When there are Finite or Infinite Ordinates and Any Slopes at the Terminals of the Range" published in the journal Biometrika.  

One of her instructors, Cargill G. Knott, wrote a letter of recommendation saying: "With fitting opportunity she has every promise of a distinguished and useful career." Pairman arrived in New York on 12 October 1919 and went on to Cambridge, Massachusetts to study at Radcliffe College, an all-women's college closely associated with the all-male Harvard College. There she studied under George David Birkhoff. Her thesis was titled 'Expansion Theorems for Solution of a Fredholm's Linear Homogeneous Integral Equation of the Second Kind with Kernel of Special Non-Symmetric Type' and was awarded a PhD in 1922. When she received her doctorate she was only the third woman to be awarded a PhD in mathematics from Radcliffe College. In that same year she married a fellow grad student, Bancroft Brown.

The couple moved to Hanover, N.H. in 1922 so Bancroft could assume a teaching position at Dartmouth College, which, at the time, was a men's school with an all-male faculty but occasionally admitting women as graduate students. Later, Pairman published a joint paper with Rudolph E. Langer in 1927.

About 1950, Pairman started focusing on teaching mathematics to blind students, learning Braille and learning how to make diagrams using her sewing machine and other household items. Her daughter Margaret later wrote, “Geometry was a particular problem, because you really need diagrams. Braille is done on paper like thin cardstock. So she rounded up all kinds of household implements like pinking shears and pastry wheels and such and created diagrams that could be felt with the fingers, like the Braille symbols. Apparently nobody had ever done this before."





2011 Rudolf Ludwig Mössbauer (31 Jan 1929 - 14 September 2011) German physicist and co-winner (with American Robert Hofstadter) of the Nobel Prize for Physics in 1961 for his researches concerning the resonance absorption of gamma-rays and his discovery in this connection of the Mössbauer effect. The Mössbauer effect occurs when gamma rays emitted from nuclei of radioactive isotopes have an unvarying wavelength and frequency. This occurs if the emitting nuclei are tightly held in a crystal. Normally, the energy of the gamma rays would be changed because of the recoil of the radiating nucleus. Mössbauer's discoveries helped to prove Einstein's general theory of relativity. His discoveries are also used to measure the magnetic field of atomic nuclei and to study other properties of solid materials. *TIS
Rudolf Mössbauer was an excellent teacher. He gave highly specialized lectures on numerous courses, including Neutrino Physics, Neutrino Oscillations, The Unification of the Electromagnetic and Weak Interactions and The Interaction of Photons and Neutrons With Matter. In 1984, he gave undergraduate lectures to 350 people taking the physics course. He told his students: “Explain it! The most important thing is, that you are able to explain it! You will have exams, there you have to explain it. Eventually, you pass them, you get your diploma and you think, that's it! – No, the whole life is an exam, you'll have to write applications, you'll have to discuss with peers... So learn to explain it! You can train this by explaining to another student, a colleague. If they are not available, explain it to your mother – or to your cat!” *Wik




2018  Branko Grünbaum ( October 2, 1929  in Osijek , Croatia ; September 14, 2018 in Seattle , Washington) was an Israeli mathematician of Yugoslavian descent who worked on discrete geometry.
A scholarship allowed Grünbaum to spend from September 1958 to June 1960 at the Institute for Advanced Study at Princeton, USA. Branko and Zdenka, with their son Ram, sailed on the T.S.S. Olympia arriving in New York on 5 September 1958 having left Lisbon exactly one month earlier. From New York they travelled by train to Princeton. After two years at Princeton, they spent one year in Seattle at the University of Washington where their second son Daniel Grünbaum was born on 2 November 1960. The family had spent the summer of 1960 at the University of California, Los Angeles, living during this time in Santa Monica. While in Seattle, Grünbaum accepted a position at the Hebrew University in Jerusalem.

There now arose a complication with his marriage. Branko and Zdenka's Orthodox Jewish marriage had been annulled because Branko's mother was not Jewish. In the City of Seattle, on 5 September 1961, Branko Grünbaum and Zdenka Bienenstock were married by a Justice of the Peace at 9:30 a.m. just before they left the United States for Jerusalem. Back at the Hebrew University his career went extremely well and he was promoted to Associate Professor in 1964. By this time he had over fifty publications and, let us note at this point, that he carried on with a remarkably high publication rate throughout his life; MathSciNet list 271 publications in total.

Grünbaum now felt slightly uneasy in Israel since, despite having a Jewish father, he had been declared a non-Jew since his mother was not Jewish. This eventually contributed to his decision to leave Israel and emigrate to North America. In 1965 he went to Michigan State University to spend a sabbatical year. While there he learnt of another marriage being annulled in similar circumstances to his own and the Israeli immigrant from the mixed marriage had her passport and citizenship revoked; this tipped the balance. It was not an easy decision, however, since Zdenka had been half way through her Ph.D. studies in Chemistry when they left Israel and she would have liked to have returned to complete the degree. Grünbaum had two possible places in North America which were particularly attractive because of his interest in geometry, the University of Toronto where Donald Coxeter was a professor, and the University of Washington in Seattle where he could work with Victor Klee. He chose the University of Washington where he was appointed to a full professorship in 1966 and remained there for the rest of his career until he retired in 2001. *SAU






Credits :
*CHM=Computer History Museum
*FFF=Kane, Famous First Facts
*NSEC= NASA Solar Eclipse Calendar
*RMAT= The Renaissance Mathematicus, Thony Christie
*SAU=St Andrews Univ. Math History
*TIA = Today in Astronomy
*TIS= Today in Science History
*VFR = V Frederick Rickey, USMA
*Wik = Wikipedia
*WM = Women of Mathematics, Grinstein & Campbell

Saturday, 12 September 2026

On This Day in Math - September 13

 


Proof is the idol before whom the pure mathematician tortures himself.

~Sir Arthur Eddington


The 256th day of the year; 256 is the smallest composite to composite power,44.

Paul Erdos conjectured that no power of 2 is the sum of distinct powers of three.

from jim wilder @ wilderlab √256 = 2 • 5 + 6

The sum of the cubes of the first 256 odd numbers is a perfect number. \( \sum\limits_{i=0}^{255} (2i+1)^3 = 8589869056\) the 6th perfect number. 

(all perfect numbers (except 6) are the sum of the cubes of first 2n odd cubes for some (but not all) n) (so \( 28 = 1^3 + 3^3\) and \( 496=1^3 + 3^3 + 5^3 + 7^3\)  and \( 8128=  1^3 + 3^3 + 5^3 + 7^3 +9^3 + 11^3 + 13^3 + 15^3\) ).   


256 is the middle number in a run of three successive numbers which are all constructible regular n-gons. 255= 3*5*17, is the product of distinct Fermat Primes, 256=28 and is a power of two, and 257 is a Fermat Prime. *HT to Don S. McDonald ‏@McDONewt


See More Math Facts for every Year Date here




EVENTS

1763 Christopher Irwin’s marine chairs were loaded onto the Princess Louisa to head off to Barbados. Irwin’s chair was being tested alongside Tobias Mayer’s lunar tables and John Harrison’s sea watch.
On 13 September 1763, the log of Lieutenant Patrick Fotheringham records how the ship “Came alongside a Hoy with two Marine Chairs and apparatus for observing the Planet Jupiter in order to finding ye Longde. at Sea the Commissioners for ye Discovery to examine these Machines under ye Direction of Adml. Tyrrell in ye course of his Voyage; Do. came on Bd Mr. Christopher Erwin the Inventor of ye Marine Machine”. *Board of Longitude project, Greenwich


1789 Wm. Herschel writes to Wollaston, "I have found that Saturn has a satellite which has hitherto escaped our observation...".

In 1789, shortly after this 40 ft instrument was operational, Herschel discovered a new moon of Saturn: Enceladus, . Discovery of a second moon (Mimas) followed, within the first month of observation. As he told Sir Joseph Banks—he directed it to the heavens (August 28th, 1789) before it had half come to its proper lustre. The stars came out well, and no sooner had he got hold of Saturn than a sixth satellite stood revealed to view! Its “younger brother” was detected September 17th.  (I have no way of explaining the date of the letter being four days earlier than the stated date of the actual discovery.  

* buffalolib.org 


Francis Wollaston (23 November 1731, London – 31 October 1815) was an English priest and astronomer.He achieved some distinction as an astronomer, becoming a member of the Royal Society in 1769 and later serving on its council. He also produced a catalog of stars and nebulae in 1789, which was used by many including his friend, William Herschel, about which he comments near the bottom of the letter.

Wollaston was suspected of unorthodox beliefs, perhaps Unitarianism, a denial of the Trinity. His actual belief, which he kept secret, was much more distinctive. It was that "the Archangel Michael had created mankind and was subsequently incarnated as Jesus". *Wik



1844 The term ABELIAN INTEGRAL is found in a letter of Sept. 8, 1844, from William Henry Fox Talbot: "What is the definition of an Abelian Integral? for it appears to me that most integrals possess the Abelian property." The letter was addressed to John Frederick William Herschel, who, in his reply of Sept. 13, 1844, wrote: "I suppose the most general definition of an Abelian Integral might be taken to be this that between ∫(x) and ∫(φ(x)) there shall subsist an algebraical relation between several such functions."  As a postscript, he adds that "a very curious photographic novelty occurred to me a day or 2 ago" in which he describes how to use a negative to create a positive image.(Talbot's original contributions included the concept of a negative from which many positive prints can be made (although the terms negative and positive were coined by Herschel), and the use of gallic acid for developing the latent image. [The Talbot letters are available here. ] *Jeff Miller Web site & Wik



1883 Opening of the University of Texas at Austin and Galveston. *VFR

By popular election in September 1881, the Main University was located at Austin and the Medical Branch, at Galveston. The academic and law departments were organized, and on September 15, 1883, the University was formally opened in the incomplete west wing of the old Main Building.

Photograph of Old Main Building at UT featuring vine growth on building. A number of students and faculty walk on the sidewalks and lounge on the grass in front of and on the sides of the lawn. Architect F. E. Ruffini of Austin designed this building in the Victorian-Gothic style. The structure was built in three stages: the west wing was completed in 1883 for The University’s first class of 221 students *Un North Texas Portal to Texas History

image from 1925




1890 Scientific American carried an article featuring the latest writing technology for the classroom, a slate pen-tip eraser. The device, invented by Mrs Emma Hudson, nestled a piece of sponge inside a rubber casing which could be wetted to remove some, or all, of the marks on a student slate. (The first pencil tip eraser for a lead pencil had been invented in 1858.)  *Sci Am

 Even after pencils became cheap and widely available in the 19th century, slates remained a standard classroom tool for decades. The main reason was economics, Paper was surprisingly expensive for much of the 1800s. Even if a pencil itself was affordable, supplying every child with notebooks and replacement paper every year was a significant cost, especially in rural or poor districts.

Many schools emphasized drill and repetition and often lessons involved repetitive exercises:

arithmetic problems,  spelling practice, handwriting drills, copying sentences

Students might work through dozens of examples in a day. Using paper for every attempt would have consumed huge amounts of supplies. Slates allowed endless practice with no waste. 

 In 1900, individual hand-held slates had largely been phased out of urban elementary schools in favor of mass-produced wooden lead pencils and paper. Conversely, they remained the primary tool in nearly all rural, one-room schoolhouses. Because a significant portion of the population lived in rural areas at the turn of the century, slates were still incredibly common.

 Mass production of the modern wood-cased lead pencil with an attached eraser (the "penny pencil") took off right around 1900. This drastically lowered the cost of paper and pencil writing, which had previously made slates the cheaper option.

 The eventual demise of slates was accelerated shortly after 1900 due to health concerns over the "spit-and-rub" method used by children to clean them. Most regions phased them out entirely between 1905 and the 1930s. *PB Notes

Both my parents were in rural schools in the period from 1924-1934 and I never talked to them on this topic. If you are nearing 100 and remember ever using slates (and even more rare, a slate pencil) please share your memories and location.




1955 Minor Planet (3167) Babcock 1955 RS. Discovered 1955 September 13 at the Goethe Link Observatory at Brooklyn, Indiana. Named in memory of Harold D. Babcock (1882-1968) and in honor of his son Horace W. Babcock, (on whose birthday it was discovered, see BIRTHS below) astronomers at Mount Wilson Observatory, the latter also serving as director of Palomar Observatory. The elder Babcock's precise laboratory studies of atomic spectra allowed others to identify the first "forbidden" lines in the laboratory and to discover the rare isotopes of oxygen. With C. E. St. John and others, he extended Rowland's tables of the solar spectrum into the ultraviolet and infrared. The Babcocks ruled excellent large gratings, including those used in the coudé spectrographs of the 2.5-m and 5-m telescopes, and they measured the distribution of magnetic fields over the solar surface to unprecedented precision. The younger Babcock invented and built many astronomical instruments, including the solar magnetograph, microphotometers and automatic guiders. By combining his polarization analyzer with the spectrograph he discovered magnetic fields in other stars, and he developed important models of sunspots and their magnetism. (M 15089) Name proposed by F. K. Edmondson. *NSEC

Harold Delos Babcock





1959 Luna II hit the moon, being the first man-made object to do so.In 1959, the first space probe to strike the moon was the Soviet Luna 2, which crashed east of the Sea of Serenity. Thirty-six hours after its launch, it was the first man-made object to reach a celestial body. *TIS On September 15, 1959, the premier of the USSR, Nikita Khrushchev, presented to the American president Dwight D. Eisenhower a copy of the spherical pennant (used onboard the Luna 2) as a gift. That sphere is located at the Eisenhower Presidential Library and Museum in Abilene, Kansas.*Wik The actual time of collision was September 13, 1959, 21:02:24 UTC




1983 Osborne Computer declares bankruptcy, two years after producing the first portable computer, the 24-pound Osborne I. Designed by company founder Adam Osborne, the \($1,795\) machine included software worth about \($1,500\). The machine featured a 5-inch display, 64 kilobytes of memory, a modem, and two 5 1/4-inch floppy disk drives.
In April 1981, Byte Magazine Editor-in-Chief Chris Morgan mentioned the Osborne I in an article on Future Trends in Personal Computing. He wrote: I recently had an opportunity to see the Osborne I in action. I was impressed with it's compactness: it will fit under an airplane seat. (Adam Osborne is currently seeking approval from the FAA to operate the unit on board a plane.) One quibble: the screen may be too small for some people's taste.*CHM

*CHM



2007 Closing date for a prize for a solution to Fermat’s last theorem. Due to inflation the prize of one hundred thousand marks has long been worthless.*VFR (perhaps not completely worthless.) In 1908 The academy of sciences of Gottingen announced a prize of one hundred thousand marks, according to the will of Dr. Paul Wolfskehl, of Darmstadt, for the proof of Fermat’s great theorem. A German industrialist and amateur mathematician, Wolfskehl bequeathed 100,000 marks to the Göttingen Academy of Sciences to be offered as a prize for a complete proof of Fermat's Last Theorem. On 27 June 1908, the Academy published nine rules for awarding the prize. Among other things, these rules required that the proof be published in a peer-reviewed journal; the prize would not be awarded for two years after the publication; and that no prize would be given after 13 September 2007, roughly a century after the competition was begun. Wiles collected the Wolfskehl prize money, then worth $50,000, on 27 June 1997.
Prior to Wiles' proof, thousands of incorrect proofs were submitted to the Wolfskehl committee, amounting to roughly 10 feet (3 meters) of correspondence. In the first year alone (1907–1908), 621 attempted proofs were submitted, although by the 1970s, the rate of submission had decreased to roughly 3–4 attempted proofs per month. According to F. Schlichting, a Wolfskehl reviewer, most of the proofs were based on elementary methods taught in schools, and often submitted by "people with a technical education but a failed career". In the words of mathematical historian Howard Eves, "Fermat's Last Theorem has the peculiar distinction of being the mathematical problem for which the greatest number of incorrect proofs have been published."*Wik




2013  On this day in 2013, Timothy Gowers and Persi Diaconis were awarded honorary degrees during a special graduation ceremony which formed part of the University of St Andrews' 600th Anniversary celebrations.  They were two of seventeen "international scholars and thinkers", "some of the best minds of our generation", who were honored in this way.  *MacTutor SAU

Gowers



BIRTHS

1755  Oliver Evans, an American mechanic and inventor, was born in Delaware on Sep. 13, 1755.  Evans first came to prominence when he designed and constructed a fully automatic flour mill. Using bucket conveyor belts, Archimedean screws, rotating stirrers, and a variety of hoppers, his mill was able to receive grain, raise it to the top of the mill, distribute it to the milling machinery, grind it to different degrees of fineness, spread and dry the grain, and then package and distribute it, all without human intervention, except to turn the machinery off and on and make repairs when necessary.  The entire mill was driven by a waterwheel.  He received a patent for his automated mill (the third U.S. patent ever granted, signed by Thomas Jefferson, but lost in the patent office fire of 1836), and his brothers implemented his design in their mills on Red Clay Creek in Delaware.

Evans’ best known effort in the realm of steam power was his Oruktor Amphibolis (amphibious digger), a steam-powered dredge that he built for the city of Philadelphia and launched in 1805.  It is described as an amphibious vehicle, but as far as I can tell, the only reason it had wheels on it was to get it to the water, since it weighed in at 17 tons.  It was only marginally successful as a steam dredge, paddling around Philadelphia on the Schuylkill River, before being dismantled in 1808, but it became better known as the years went on, especially after Evans' death in 1819.  Wood engravings of the Oruktor were included in nearly every history of steam power from 1830 on.  *Linda Hall org

*Linda Hall org




1873 Constantin Caratheodory born. (13 Sep 1873; 2 Feb 1950) He worked on the calculus of variations and the theory of real functions. He is the only modern Greek mathematician “who does not suffer by comparison with the famous names of Greek antiquity.” *VFR.

At first he trained as an engineer, working on irrigation projects in Egypt (1896–1900). The long, solitary nights in the desert gave him time to study mathematics seriously on his own. This late turn is one of the more unusual stories in his career: he was nearly 30 before devoting himself to pure mathematics.

He studied mathematics at Göttingen (under Hilbert and Klein), then taught at Bonn, Göttingen, and Berlin.

In 1919, invited by Prime Minister Venizelos, he went to Smyrna to help establish a new Greek university.

He became rector and worked tirelessly to develop its curriculum and library. When Smyrna was destroyed during the Greco-Turkish War, Carathéodory personally arranged for the university’s library — about 30,000 volumes — to be saved. He oversaw their transfer by ship to Athens, where they later formed the core of the library of the University of Athens. His courage and quick action meant that an entire academic collection survived a city’s destruction.

Carathéodory was known for his sharp memory. Hilbert once teased him about it:  At Göttingen, Carathéodory would sometimes interrupt with, “Herr Professor, you proved this result in your lecture on November 17, 1905.”

Hilbert chuckled and is said to have replied: “Carathéodory, you are my living notebook.”

In his lectures, Carathéodory sometimes got so absorbed in computations that he would fill the blackboard with perfectly neat formulas, then suddenly exclaim (half to himself): “Yes! That’s elegant enough to be true.” His students recalled that he treated mathematics like a kind of art. AGerman mathematician of Greek origin who made important contributions to the theory of real functions and to the theory of point-set measure. He demonstrated that the calculus of variations (the theory of maxima and minima in curves) could be applied not just to smooth curves, but also those with corners. He also contributed to thermodynamics and helped develop Einstein's special theory of relativity. *TIS



1885 Wilhelm Blaschke  (13 Sep 1885; 17 Mar 1962) German mathematician whose major contributions to geometry concerned kinematics and differential geometry. Kinetic mapping (important later in the axiomatic foundations of various geometries) he both discovered and established it as a tool in kinematics. He also initiated topological differential geometry (the study of invariant differentiable mappings)*TIS



1912 Horace Welcome Babcock (13 Sep 1912; 29 Aug 2003) was a American astronomer, son of Harold Babcock. Working together, they were the first to measure the distribution of magnetic fields over the surface of the Sun. Horace invented and built many astronomical instruments, including a ruling engine which produced excellent diffraction gratings, the solar magnetograph, and microphotometers, automatic guiders, and exposure meters for the 100 and 200-inch telescopes. By combining his polarizing analyzer with the spectrograph he discovered magnetic fields in other stars. He developed important models of sunspots and their magnetism, and was the first to propose adaptive optics.*TIS



1913 Captain Herman_H._Goldstine (September 13, 1913 – June 16, 2004), mathematician, computer scientist and scientific administrator, was one of the original developers of ENIAC, the first of the modern electronic digital computers.*Wik



1920 William Bowen Bonnor ( 9 September 1920 – 17 August 2015) is a mathematician and gravitation physicist best known for his research into astrophysics, cosmology and general relativity. For most of his academic career he has been a professor of mathematics at the University of London.

Bonnor's research was published in about 150 papers in various scientific journals. The most cited paper described the effect of gravitation on Boyle's law; this has been extensively used in the theory of star formation. Another well-cited paper applies Newtonian dynamics to the formation of galaxies in cosmology. However, most of Bonnor's research was on the theory of general relativity.*Wik






1921 Albert "Tommy" Wilansky (13 September 1921, St. John's, Newfoundland – 3 July 2017, Bethlehem, Pennsylvania) was a Canadian-American mathematician, known for introducing Smith numbers.

Wilansky was educated as an undergraduate at Dalhousie University, where he received an M.A. in mathematics in 1944. From 1944 to 1947 he was a graduate student at Brown University. In 1947 he received his Ph.D. with advisor Clarence Raymond Adams and dissertation An application of Banach linear functionals to the theory of summability.

From 1948 until his official retirement in 1992, Wilansky was a faculty member of the mathematics department of Lehigh University.

He was the university’s Distinguished Professor of Mathematics for the final 14 years of his tenure. During his 44 years at Lehigh he was a Fulbright visiting professor several times, at universities in Reading (1972–1973), London (1973), Tel Aviv (1981), and Berne (1981). Outside of academia he was a consultant for the Frankford Arsenal for the year 1957–1958.

Wilansky did research in analysis, specializing in summability theory, linear topological spaces, Banach algebras, and functional analysis. He was the author of several books and the author or co-author of more than 80 articles. He lectured at over 50 different universities. In 1969 he received the Mathematical Association of America's Lester R. Ford Award for his 1968 article Spectral Decomposition of Matrices for High School Students. *Wik

In number theory, a Smith number is a composite number for which, in a given number base, the sum of its digits is equal to the sum of the digits in its prime factorization in the same base. In the case of numbers that are not square-free, the factorization is written without exponents, writing the repeated factor as many times as needed.

Smith numbers  were so-named by Wilansky  as he noticed the property in the phone number (493-7775) of his brother-in-law Harold Smith:

4937775 = 3 · 5 · 5 · 65837   while  4 + 9 + 3 + 7 + 7 + 7 + 5 = 3 + 5 + 5 + (6 + 5 + 8 + 3 + 7) in base 10.

Other Smith numbers  are 4, 22, 27, 58, 85, 121, 166..... (OEIS A006753)



1923 Peter K Henrici (13 Sept 1923 , 13 March 1987) He made "major contributions to preserving and enriching our mathematical heritage. His books and papers have helped greatly in maintaining numerical analysis as a subject with beauty, order, and structure, in the spirit of the great pioneers of the past. He keeps reminding us to ask what Gauss would have done with a parallel computer - or with a pocket calculator."
"Henrici was truly an internationally recognized numerical analyst, having written 11 books and over 80 research papers. A very cultured person who was also a gifted pianist, he was an outstanding teacher particularly interested in helping younger mathematicians. His lectures showed great polish and inspired many. His guidance and unselfish contributions as an editor have helped make Numerische Mathematik the respected journal it is. For this alone, we owe him a great debt of gratitude." *SAU



1926 Sidney David Drell (September 13, 1926 – December 21, 2016) was an American theoretical physicist and arms control expert. He is a professor emeritus at the Stanford Linear Accelerator Center (SLAC) and a senior fellow at Stanford University's Hoover Institution. Drell is a noted contributor in the field of quantum electrodynamics and particle physics. The Drell–Yan process is partially named after him. He was one of the winners of the 2000 Enrico Fermi Award.*Wik





DEATHS


1296 Johannes Campanus (1220 in Novara, Italy - 13 Sept 1296 in Viterbo, Italy) also known as Campanus of Novara, was an Italian mathematician who published a Latin edition of Euclid's Elements. He also wrote on astronomy.*SAU

As a preacher, Campanus knew the Anabaptist prophet Melchior Hoffman (c.1495–1543). Hoffman had developed a Zwinglian view of the Eucharist. Martin Luther himself was alarmed at this. At a colloquy of preachers in Flensburg on 8 April 1529, Hoffman, Campanus, and others were put on the defensive. Hoffman maintained (against the "magic" of the Lutheran interpretation) that the function of the Eucharist, like that of preaching, is nothing more than an appeal for spiritual union with Christ.*Wik




1930  László Rátz (9 April 1863 in Sopron – 30 September 1930 in Budapest) was a Hungarian mathematics high school teacher best known for educating such people as John von Neumann and Nobel laureate Eugene Wigner. He was a legendary teacher of "Budapest-Fasori Evangélikus Gimnázium", the Budapest Lutheran Gymnasium, a famous secondary school in Budapest in Hungary.

Eugene Wigner recalled that, "Many teachers had great skill but none could invoke the beauty of the subject like Ratz."



1940 Myron Mathisson (15 Dec 1897 , 13 Sept 1940) was a Polish Jew known for his work on the equations of motion of bodies in general relativity and for developing a new method to analyze the properties of fundamental solutions of linear hyperbolic differential equations. In particular, he derived the equations for a spinning body moving in a gravitational field and proved, in a special case, the Hadamard conjecture on the class of equations that satisfy the Huygens principle. His work still exerts influence on current research.*Cornell Univ Library



1975 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



2021 Antony Hewish FRS FInstP (11 May 1924 – 13 September 2021) was a British radio astronomer who won the Nobel Prize for Physics in 1974 (together with fellow radio-astronomer Martin Ryle) for his role in the discovery of pulsars. ( Several prominent scientists protested the omission of Bell Burnell, though she maintained that the prize was presented appropriately given her student status at the time of the discovery) He  was also awarded the Eddington Medal of the Royal Astronomical Society in 1969

In late Nov 1967, using a radio telescope, Hewish and Ph.D. student Jocelyn Bell  observed an unusual signal corresponding to a sharp burst of radio energy at a regular interval of approximately one second. It is believed that rapidly rotating neutron stars with intense electromagnetic fields emit radio waves from their north and south poles. From a great distance, these radio emissions are perceived in pulses, similar to the way one sees the light from a lighthouse's rotating lantern. Hewish and Bell's discovery served as the first evidence of this phenomenon.





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