Wednesday, 29 October 2025

Barycenter....History and Etymology of Math terms

 On This Day in Math - October 29 Barycenter : The word barycenter is another term for the center of gravity or centroid. The Greek root is barus which generally refers to weighty or heavy. The more ancient Indo-European root seems to have come from a word like "gwerus" and has relatives in our words for gravity and grave.

The term "centroid" is of recent coinage (1814). William Whewell (1794–1866) is well-known for coining numerous scientific terms (“scientist,” “anode,” “cathode,” etc.) . Given his linguistic creativity and active engagement in mathematics around 1814, some attribute centroid to him, though no surviving text can confirm this specifically. Centroid is used as a substitute for the older terms "center of gravity" and "center of mass" when the purely geometrical aspects of that point are to be emphasized. The term is peculiar to the English language; 

Another word derived from the same root is baryon, the name for a family of particles that are heavier (more massive) than mesons. The word barometer also comes from the same root and is so named because, in a sense, it measures how heavy the air is. Another related word still in current use is baritone, which literally means heavy voiced. The science names for the chemical barium and the ore from which we obtain it, barite, also called "heavy spar", are both from the same root.


The History of Math web site at St. Andrews University in Scotland credits the creation of barycenters to August Möbius (1790-1868):

In 1827 Möbius published Der barycentrische Calcul, a geometrical book which studies transformations of lines and conics. The novel feature of this work is the introduction of barycentric coordinates. Given any triangle ABC then if weights a, b and c are placed at A, B and C respectively then a point P, the center of gravity, is determined. Möbius showed that every point P in the plane is determined by the homogeneous coordinates [a,b,c], the weights required to be placed at A, B and C to give the center of gravity at P. The importance here is that Möbius was considering directed quantities, an early appearance of vectors.


On This Day in Math - October 29

   





Allez en avant, et la foi vous viendra
Push on and faith will catch up with you.

~Jean d'Alembert [advice to those who questioned the calculus](probably also great for students struggling with mathematics at any level)


The 302nd day of the year; There are 302 ways to play the first three moves in checkers.

302 is the sum of three consecutive squares 92+102+112  

302 is a semiprime, 2 x 151.  Its reversal 203 = 7 x 29, is also a semiprime


EVENTS


1669 Newton, aged twenty-six, appointed Lucasian Professor at Cambridge. This post required Newton to lecture once each week on “some part of Geometry, Astronomy, Geography, Optics, Statics, or some other Mathematical discipline,” and to deposit ten of those lectures in the library each year. The students were required to attend, but like all other requirements they ignored this one too. We know of only three people who attended a lecture at Cambridge by Newton. [Westfall 208–210; Works, 3, xv] *VFR

The post was founded in 1663 by Henry Lucas, who was Cambridge University's Member of Parliament in 1639–1640, and it was officially established by King Charles II on 18 January 1664. It was described by The Daily Telegraph as one of the most prestigious academic posts in the world. Since its establishment, the professorship has been held by, among others, Isaac Newton, Charles Babbage, George Stokes, Joseph Larmor, Paul Dirac, and Stephen Hawking.

Michael Elmhirst Cates FRS FRSE HonFInstP  is the 19th Lucasian Professor of Mathematics at the University of Cambridge and has held this position since 1 July 2015. He was previously Professor of Natural Philosophy at the University of Edinburgh, and has held a Royal Society Research Professorship since 2007. His work focuses on the theory of soft matter, such as polymers, colloids, gels, liquid crystals, and granular material.

The First Lucasian Professor at Cambridge was Isaac Barrow

Statue of Isaac Barrow in the chapel of 
Trinity College, Cambridge*Wik



1675 Leibniz first used the integral sign. Also first used “d”. He also constructed what he calls the “triangulum characteristicum,” which had been used before him by Pascal and Barrow. [Cajori, History of Mathematical Notations, vol. 2, p. 2; Struik’s Source Book mistakenly has 26 October]

VFR Historical notes for the calculus classroom ,
In these same pages he will write examples of the integrals of x2 and x3,and then illustrate that a constant multiple may be taken outside the integral as shown in the image below.

On the left is Liebniz integral sign with a vincula in place of todays parentheses to show that he is integrating the quantity (a/b) l   Then the open bottomed box is Liebniz symbol for equality,then he shows the constant (a/b) multiplied by the integral of l .

At this point, Leibniz does not include the dx, as in \( \int x^2 = \frac{x^3}{3} \)  even though it seems his definition of an integral as a summation would seem to require it.  By 1686 he will adopt it, as he wrote \( \int \rho dx \)


1745/46 The first Polish encyclopedia, titled Nowe Ateny, or “New Athens,” was published.  It differed greatly in style from the encyclopedias of today. It included entries for dragons, headless humans, and an ant that could eat a pound of meat. The author had little time for mundane entries like “horse,” whose description was simply “What a horse is like, anyone can see.” *Britannica





1856 William Rowan Hamilton submits a paper on "New Roots of Unity" which will be the foundation of his Icosian Calculus, and the Icosagon game he used as a simplification of the operations of the group. The symbols of the icosian calculus can be equated to moves between vertices on a dodecahedron. Hamilton’s work in this area resulted indirectly in the terms Hamiltonian circuit and Hamiltonian path in graph theory. *Wik
The game set shown below included numbered pegs that could track your path around the twenty vertices of the dodecahedron


1878 Patent issued for Odhner calculating machine. *VFR Willigot T. Odhner was granted a patent for a calculating machine that performed multiplications by repeated additions. The patent, a modified and compact version of Gottfried von Leibniz stepped wheel, was acquired and embodied in Brunsviga calculators that sold into 1950s.*CHM





1929 "Black Tuesday", the great USA stock market crash. About 16 million shares were traded, and the Dow lost an additional 30 points, or 12%.. "Anyone who bought stocks in mid-1929 and held onto them saw most of his or her adult life pass by before getting back to even." Richard M. Salsman *Wik

 In fact it wasn't until October of 1954 before it regained its 1929 High,  The Dow Jones Industrial Average dropped significantly from a high of around 381 in September 1929 to a low of 41.22 in July 1932, losing nearly 90% of its value during the 1929 crash and subsequent Great Depression. After reaching this low point, it gradually began to recover, peaking again in 1937 before experiencing another sharp decline in 1937-1938. By 1940, the index had not yet returned to its 1929 peak but was on an upward trend, finishing the year around 150.




1964 Asteroid "Lucifer" is discovered by astronomer Elizabeth Roemer. amhistorymuseum ‏@amhistorymuseum Roemer was the winner of the 1946  National Westinghouse Science Talent Search, and became Professor Emerita, Lunar and Planetary Laboratory, University of Arizona. *Smithsonian Institution Archives (Ok, it's pure trivia, but is she somehow related to Ole, who first measured the speed of light???)

Elizabeth Roemer was an active member of the astronomy community until her death in 2016. She became a member of the Friends of Lowell Observatory in 2006, as well as a member of the Percival Lowell Society.

1930 Lucifer, provisional designation 1964 UA, is a carbonaceous asteroid from the outer regions of the asteroid belt, approximately 34 kilometers in diameter. It was discovered on 29 October 1964, by American astronomer Elizabeth Roemer at the Flagstaff station (NOFS) of the United States Naval Observatory (USNO). It is named after Lucifer, the "shining one" or "light-bearer" from the Hebrew Bible.




1985 On October 29th, 1985, the 329th birthday of Edmond Halley, the British threw a big party in honor of the return of Halley's Comet. The Halley's Comet Royal Gala was held at Wembley Conference Centre, London. It was a combination Variety Show and "Who's Who" in British Society, hosted by Princess Anne of the British Royal Family. *Joseph M. Laufer, Halley's Comet Society, USA

Halley's Comet was approaching Earth in 1985, making the 1985-86 apparition the most significant for centuries and the subject of major scientific and public interest. During this time, ground-based telescopes and several spacecraft, including the European Space Agency's Giotto probe, were deployed for close-up studies, though the comet's closest approach to Earth was in April 1986. Halley's Comet was last visible from Earth in 1986 and is not expected to return until 2061.  *PB

TIME Magazine Cover: Halley's Comet - Dec. 16, 1985 




In 1991, space probe Galileo become the first human object to fly past an asteroid, Gaspra, making its closest approach at a distance of 1,604 km, passing at a speed of 8 km/sec (5 mi/sec). The encounter provided much data, including 150 images, which showed Gaspra has numerous craters indicating it has suffered numerous collisions since its formation. Gaspra is about 20-km long and orbits the Sun in the main asteroid belt between Mars and Jupiter. Gaspra, asteroid 951, was discovered by Ukrainian astronomer Grigoriy N. Neujamin (1916) who named it after a Black Sea retreat. In the photograph, subtle color variations have been exaggerated by NASA to highlight changes in reflectivity, surface structure and composition. *TIS



1998, Nearly four decades after he became the first American to orbit Earth, John Glenn is relaunched into space. *@HISTORYmag

 Nearly four decades after his famous orbital flight, the 77-year-old Glenn became the oldest human ever to travel in space. During the nine-day mission, he served as part of a NASA study on health problems associated with aging.



On Oct. 29, 1998, the gavel came down at the auction of an ugly-looking medieval manuscript (first image above). Splotched with mildew, displaying a Greek prayer book of no special interest, the codex appeared to have little going for it except its age, which was 13th century. But one important feature had brought bidders from around the globe and on the phone to Christie’s in New York: the manuscript was a palimpsest, which means the parchment had been scraped and reused, and there was another text, several centuries older and only faintly visible, lying under the prayer text. That "other text" proved to be a collection of seven of the works of Archimedes, in Greek, including a treatise, "The Method," for which no other copy exists.

The Archimedes palimpsest first came to light in 1906, when Johan Heiberg, a scholar of ancient Greek mathematics, had examined it in Constantinople and recognized the underlying script as Archimedean. The manuscript subsequently turned up in the library of a French collector, then disappeared for 75 years, and then emerged again in 1998, when Christie’s offered it up at auction (second image). When the gavel dropped, the winning bid was an even $2 million (with another $200,000 in premiums added on top). *Linda Hall Org






BIRTHS

1897 Edwin James George Pitman  (29 October 1897 – 21 July 1993)  was born in Melbourne on 29 October 1897 and died at Kingston near Hobart on 21 July 1993.  In 1920 he completed the degree course and graduated B.A. (1921), B.Sc. (1922) and M.A. (1923). In the meantime he was appointed Acting Professor of Mathematics at Canterbury College, University of New Zealand (1922-23). He returned to Australia when appointed Tutor in Mathematics and Physics at Trinity and Ormond Colleges and Part-time Lecturer in Physics at the University of Melbourne (1924-25). In 1926 Pitman was appointed Professor of Mathematics at the University of Tasmania, a position he held until his retirement in 1962.
Pitman described himself as 'a mathematician who strayed into Statistics'; nevertheless, his contributions to statistical and probability theory were substantial.
Pitman was active in the formation of the Australian Mathematical Society in 1956. He also took an active part in the Summer Research Institutes organized by the Mathematical Society, and used them as a sounding board for his research on statistical inference.
He was a renowned member of the Statistical Society of Australia, attending its biennial conferences. In 1978 the Statistical society established the Pitman Medal.
Pitman presented the first systematic account of non-parametric inference and lectured extensively on the subject, both in Australia and in the United States. The kernel of the subject, as described by him, is 'Suppose that the sum of two samples A, B is the sample C. Then A, B are discordant if A is an unlikely sample from C.' Again, he writes, 'The approach to the subject, starting from the sample and working towards the population instead of the reverse, may be a bit of a novelty'; and later, 'the essential point of the method is that we do not have to worry about the populations which we do not know, but only about the sample values which we do know'.
The notes of the 'Lectures on Non-parametric Inference' given in the United States, though never published, have been widely circulated and have had a major impact on the development of the subject. Among the new concepts introduced in these Lectures are asymptotic power, efficacy, and asymptotic relative efficiency.
A major contribution to probability theory is his elegant treatment of the behavior of the characteristic function in the neighborhood of the origin, in three papers. This governs such properties as the existence of moments. There are also interesting properties of the Cauchy distribution, and of subexponential distributions.
On his death, on 21 July 1993, Edwin was buried at the Hobart Regional Cemetery in Kingston. He lives on in the memory of many of us who are grateful for his life and legacy.
*Evan J. Williams, Australian Academy of Science




1910 Dan Pedoe (29 October 1910, London – 27 October 1998, St Paul, Minnesota, USA) was an English-born mathematician and geometer with a career spanning more than sixty years. In the course of his life he wrote approximately fifty research and expository papers in geometry. He is also the author of various core books on mathematics and geometry some of which have remained in print for decades and been translated into several languages. These books include the three-volume Methods of Algebraic Geometry (which he wrote in collaboration with W. V. D. Hodge), The Gentle Art of Mathematics, Circles: A Mathematical View, Geometry and the Visual Arts and most recently Japanese Temple Geometry Problems: San Gaku (with Hidetoshi Fukagawa). *Wik   [His book on San Gaku is one of the most beautiful math books I have ever owned.  Many of the temple plaques are the work of working peasants who learned and created beautiful geometric works as offerings to the gods. Soddy's hexlet, thought previously to have been discovered in the west in 1937, had been discovered on a sangaku dating from 1822.]

Replica of Sangaku at Hōtoku museum in Samukawa Shrine.




1925 Nathan Joseph Harry Divinsky (October 29, 1925 – June 17, 2012) was a Canadian mathematician, university professor, chess master, chess writer, and chess official. Divinsky was also known for being the former husband of the 19th prime minister of Canada, Kim Campbell. Divinsky and Campbell were married from 1972 to 1983.

Divinsky received a Bachelor of Science from the University of Manitoba in 1946. He received a Master of Science in 1947, and a PhD in Mathematics under A. A. Albert in 1950 from the University of Chicago after which he returned to Winnipeg and was on the staff of the Mathematics Department of the University of Manitoba for most of the '50s. Divinsky then moved to Vancouver where he served as a mathematics professor, and also as an assistant dean of science, at the University of British Columbia in Vancouver, where he spent the remainde] of his professional career.

He was featured in many segments relating to mathematics and chess on the Discovery Channel Canada program @discovery.ca, now called Daily Planet. During the first two seasons of the show, he presented a weekly contest segment emphasizing math puzzles.

Divinsky served on the Vancouver School Board, from 1974 to 1980, and was the Chair from 1978 to 1980. He served as an alderman on Vancouver's city council from 1981 to 1982.

Divinsky learned his early chess as a teenager at the Winnipeg Jewish Chess Club, along with Yanofsky. He tied for 3rd–4th places in the Closed Canadian Chess Championship, held at Saskatoon 1945, with 9.5/12, along with John Belson; the joint winners were Yanofsky and Frank Yerhoff at 10.5/12. In the 1951 Closed Canadian Chess Championship, held at Vancouver, Divinsky scored 6/12 to tie for 5th–7th places. He won the Manitoba Championship in both 1946 and 1952, and finished runner-up in 1945. He tied for first place in the 1959 Manitoba Open. Divinsky scored 7.5/11 at Bognor Regis 1966, finishing in a tie for 7–13th places.

He represented Canada twice at the Chess Olympiads, in 1954 at Amsterdam (second reserve board, 0.5/1), and in 1966 at Havana (second reserve board, 4.5/8). Divinsky served as playing captain for both teams, and was the non-playing captain for the 1988 Canadian Olympiad team.[9] Divinsky attained the playing level of National Master in Canada, and received through the Commonwealth Chess Association (founded by English Grandmaster Raymond Keene) the honorary title of International Master (although he did not receive this title officially from FIDE, the World Chess Federation).

Divinsky was also a Life Master at Bridge from 1972.




1925 Klaus Friedrich Roth (29 October 1925 – 10 November 2015) German-born British mathematician who was awarded the Fields Medal in 1958. His major work has been in number theory, particularly the analytic theory of numbers. He solved in the famous Thue-Siegel problem (1955) concerning the approximation to algebraic numbers by rational numbers (for which he won the medal). Roth also proved in 1952 that a sequence with no three numbers in arithmetic progression has zero density (a conjecture of Erdös and Turán of 1935).*TIS






DEATHS


1783 Jean le Rond D'Alembert (16 Nov 1717, 29 Oct 1783) was abandoned by his parents on the steps of Saint Jean le Rond, which was the baptistery of Notre-Dame, qv in Section 7-A-1. Foster parents were found and he was christened with the name of the saint. [Eves, vol. II, pp. 32 33. Okey, p. 297.] When he became famous, his mother attempted to reclaim him, but he rejected her. *VFR Known for his work in various fields of applied mathematics, in particular dynamics. In 1743 he published his Traité de dynamique (Treatise on Dynamics). The d'Alembert principle extends Newton's third law of motion, that Newton's law holds not only for fixed bodies but also for free moving bodies. D'Alembert also wrote on fluid dynamics, the theory of winds, the properties of vibrating strings and conducted experiments on the properties of sound . His most significant purely mathematical innovation was his invention and development of the theory of partial differential equations. He published eight volumes of mathematical studies (1761-80). He was editor of the mathematical and scientific articles for Denis Diderot's Encyclopédie.*TIS




1917 Giovanni Battista Guccia (21 Oct 1855 in Palermo, Italy - 29 Oct 1914 in Palermo, Italy) Guccia's work was on geometry, in particular Cremona transformations, classification of curves and projective properties of curves. His results published in volume one of the Rendiconti del Circolo Matematico di Palermo were extended by Corrado Segre in 1888 and Castelnuovo in 1897. *SAU




1921 Konstantin Alekseevich Andreev (26 March 1848 in Moscow, Russia - 29 Oct 1921 Near Sevastopol, Crimea) Andreev is best known for his work on geometry, although he also made contributions to analysis. In the area of geometry he did major pieces of work on projective geometry. Let us note one particular piece of work for which he has not received the credit he deserves. Gram determinants were introduced by J P Gram in 1879 but Andreev invented them independently in the context of problems of expansion of functions into orthogonal series and the best quadratic approximation to functions. *SAU




1931 Gabriel Xavier Paul Koenigs (17 January 1858 Toulouse, France – 29 October 1931 Paris, France) was a French mathematician who worked on analysis and geometry. He was elected as Secretary General of the Executive Committee of the International Mathematical Union after the first world war, and used his position to exclude countries with whom France had been at war from the mathematical congresses.
He was awarded the Poncelet Prize for 1913.*Wik




1933 Paul Painlevé ( 5 December 1863 – 29 October 1933)  worked on differential equations. He served twice as prime-minister of France. *SAU

Some differential equations can be solved using elementary algebraic operations that involve the trigonometric and exponential functions (sometimes called elementary functions). Many interesting special functions arise as solutions of linear second order ordinary differential equations. Around the turn of the century, Painlevé, É. Picard, and B. Gambier showed that of the class of nonlinear second order ordinary differential equations with polynomial coefficients, those that possess a certain desirable technical property, shared by the linear equations (nowadays commonly referred to as the 'Painlevé property') can always be transformed into one of fifty canonical forms. Of these fifty equations, just six require 'new' transcendental functions for their solution. These new transcendental functions, solving the remaining six equations, are called the Painlevé transcendents, and interest in them has revived recently due to their appearance in modern geometry, integrable systems and statistical mechanics *Wik



1951 Robert Aitken (31 Dec 1864, 29 Oct 1951) American astronomer who specialized in the study of double stars, of which he discovered more than 3,000. He worked at the Lick Observatory from 1895 to 1935, becoming director from 1930. Aitken made systematic surveys of binary stars, measuring their positions visually. His massive New General Catalogue of Double Stars within 120 degrees of the North Pole allowed orbit determinations which increased astronomers' knowledge of stellar masses. He also measured positions of comets and planetary satellites and computed orbits. He wrote an important book on binary stars, and he lectured and wrote widely for the public. *TI



1959 Edith Clarke (February 10, 1883 – October 29, 1959) was an American electrical engineer. She was the first woman to be professionally employed as an electrical engineer in the United States, and the first female professor of electrical engineering in the country. She was the first woman to deliver a paper at the American Institute of Electrical Engineers; the first female engineer whose professional standing was recognized by Tau Beta Pi, the oldest engineering honor society and the second oldest collegiate honor society in the United States; and the first woman named as a Fellow of the American Institute of Electrical Engineers. She specialized in electrical power system analysis and wrote Circuit Analysis of A-C Power Systems.

After being orphaned at age 12, she was raised by an older sister. She used her inheritance to study mathematics and astronomy at Vassar College, where she graduated in 1908.


Unable to find work as an engineer, Clarke went to work for General Electric as a supervisor of computers in the Turbine Engineering Department. During this time, she invented the Clarke calculator, an early graphing calculator, a simple graphical device that solved equations involving electric current, voltage and impedance in power transmission lines. The device could solve line equations involving hyperbolic functions ten times faster than previous methods. She filed a patent for the calculator in 1921 and it was granted in 1925.

She was offered a job by GE as a salaried electrical engineer in the Central Station Engineering Department – the first professional female electrical engineer in the United States. She retired from General Electric in 1945.

Her background in mathematics helped her achieve fame in her field. On February 8, 1926, as the first woman to deliver a paper at the American Institute of Electrical Engineers' (AIEE) annual meeting, she showed the use of hyperbolic functions for calculating the maximum power that a line could carry without instability. The paper was of importance because transmission lines were getting longer, leading to greater loads and more chances for system instability, and Clarke's paper provided a model that applied to large systems.


In 1943, Clarke wrote an influential textbook in the field of power engineering, Circuit Analysis of A-C Power Systems, based on her notes for lectures to GE engineers. This two-volume textbook teaches about her adaption of the symmetrical components system, in which she became interested while working for the second time at GE.

In 1947, she joined the faculty of the Electrical Engineering Department at the University of Texas at Austin, making her the first female professor of electrical engineering in the country.

Ms. Clarke died in 1959 at the age of seventy-six.

Her calculator was a dynamic nomogram






1993 Lipman Bers (May 22, 1914 – October 29, 1993) was an American mathematician born in Riga who created the theory of pseudoanalytic functions and worked on Riemann surfaces and Kleinian groups. He was also known for his work in human rights activism.

Bers' doctoral work was on the subject of potential theory. While in Paris, he worked on Green's function and on integral representations. After first moving to the US, while working for YIVO, he researched Yiddish mathematics textbooks rather than pure mathematics.

At Brown, he began working on problems of fluid dynamics, and in particular on the two-dimensional subsonic flows associated with cross-sections of airfoils. At this time, he began his work with Abe Gelbart on what would eventually develop into the theory of pseudoanalytic functions. Through the 1940s and 1950s he continued to develop this theory, and to use it to study the planar elliptic partial differential equations associated with subsonic flows. Another of his major results in this time concerned the singularities of the partial differential equations defining minimal surfaces. Bers proved an extension of Riemann's theorem on removable singularities, showing that any isolated singularity of a pencil of minimal surfaces can be removed; he spoke on this result at the 1950 International Congress of Mathematicians and published it in Annals of Mathematics.

Later, beginning with his visit to the Institute for Advanced Study, Bers "began a ten-year odyssey that took him from pseudoanalytic functions and elliptic equations to quasiconformal mappings, Teichmüller theory, and Kleinian groups". With Lars Ahlfors, he solved the "moduli problem", of finding a holomorphic parameterization of the Teichmüller space, each point of which represents a compact Riemann surface of a given genus. During this period he also coined the popular phrasing of a question on eigenvalues of planar domains, "Can one hear the shape of a drum?", used as an article title by Mark Kac in 1966 and finally answered negatively in 1992 by an academic descendant of Bers. In the late 1950s, by way of adding a coda to his earlier work, Bers wrote several major retrospectives of flows, pseudoanalytic functions, fixed point methods, Riemann surface theory prior to his work on moduli, and the theory of several complex variables. In 1958, he presented his work on Riemann surfaces in a second talk at the International Congress of Mathematicians 

In 1961, Bers was elected a Fellow of the American Academy of Arts and Sciences, and in 1965 he became a Fellow of the American Association for the Advancement of Science. He joined the National Academy of Sciences in 1964. He was a member of the Finnish Academy of Sciences, and the American Philosophical Society. He received the AMS Leroy P. Steele Prize for mathematical exposition in 1975 for his paper "Uniformization, moduli, and Kleinian groups". In 1986, the New York Academy of Sciences gave him their Human Rights Award. In the early 1980s, the Association for Women in Mathematics held a symposium to honor Bers' accomplishments in mentoring women mathematicians.*Wik

Photo by Paul Halmos *SAU



1993 Robert Palmer Dilworth (December 2, 1914 – October 29, 1993) was an American mathematician. His primary research area was lattice theory; his biography at the MacTutor History of Mathematics archive states "it would not be an exaggeration to say that he was one of the main factors in the subject moving from being merely a tool of other disciplines to an important subject in its own right". He is best known for Dilworth's theorem (Dilworth 1950) relating chains and antichains in partial orders; he was also the first to study antimatroids (Dilworth 1940). Dilworth advised 17 Ph.D. students and as of 2010 has 373 academic descendants listed at the Mathematics Genealogy Project, many through his student Juris Hartmanis, a noted complexity theorist.*Wik



2013 Douglas Samuel Jones (10 January 1922 – 29 November 2013) was a mathematician and electrical engineer known for his works in the field of electromagnetism.

In 1940, Jones began studying electrical engineering at Clarendon Laboratory of the Corpus Christi College, Oxford University.

Jones joined the RAF in 1942 and graduated MA in applied mathematics from Oxford in 1947. He then went to Massachusetts Institute of Technology to study electrical engineering, but switched to physics, studying under Victor Weisskopf, Herman Feshbach, and Robley Evans. In the same years he led a research team looking at equipment for night fighter operations. Awarded MBE in 1945 for his work with the RAF.

Jones then worked as a lecturer at Manchester University. In 1957 he was appointed chair of Mathematics at the University of Keele.

During his time at Keele, Jones wrote the book The Theory of Electromagnetism in 1964 which established him as a leader in this field.

In 1965, Jones was appointed to the Ivory Chair of Applied Mathematics at Queen's College, Dundee, then part of the University of St Andrews, but which became the University of Dundee in 1967.

Jones retired from the University of Dundee in 1992, gaining the title Emeritus Professor.

He was described by The Scotsman as "one of the most outstanding British mathematicians of his generation". *Wik

Jones received many honours for his outstanding contributions. He was elected a fellow of the Royal Society of Edinburgh (1967), a fellow of the Royal Society of London (1968), awarded the Keith Prize by the Royal Society of Edinburgh (1971-73), given an Honorary DSc from the University of Strathclyde (1975), awarded the Marconi Prize by the Institute of Electrical Engineers (1975), made an Honorary Fellow of Corpus Christi College Oxford (1980), awarded the Balthasar van der Pol Gold Medal by the International Union of Radio Science (1981), awarded the Naylor Prize and Lectureship of the London Mathematical Society (1986), elected a fellow of the Institution of Electrical Engineers (1989), made a life member of the Institute of Electrical and Electronics Engineers (2013).*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





Tuesday, 28 October 2025

Versine, Haversine... History and Etymology of Math Terms Versine

    Versine

The versine of an angle, A, is an almost extinct expression for the quantity 1-cos(A). Up to the 1600's this was probably the second most common trigonometric value used. The Latin word versed relates to turning, and the "versed sine" was, in essence, the sine turned 90 degrees.

In 1835, James Inman introduced the term haversine to describe a value of 1/2 of the versine, "half-versine". The haversine was an important formula in spherical geometry and navigation, since it gave a simple way to find the approximate distance between two points on the earth using the Latitudes and Longitudes. If we consider two points on the unit sphere, with positions given as (lat1, long1) and (lat2, long2) in radians, then the distance between them is given by 

 

where dLat and dLong are the differences in the latitudes and longitudes. Tables for Navigation contained both Hav(x) and its inverse invHav(x) and the logs of these values to assist in prosthaphaeresis . To find the distances on the earth, the answer would be multiplied by the radius of the earth. According to Jeff Miller's web site, the word first appeared in the third edition of Navigation and Nautical Astronomy for the use of British Seamen.

The mathematical terms converse and inverse are both from the same root. Many other words come less directly from this root. A plow turns dirt up and over and creates a furrow, a straight line of dirt along the ground. Things laid out along a straight line were sometimes said to resemble the furrow and called verses, and thus words in a line of a poem became a verse. To reverse is to turn back, and the obverse side is the side you see when you turn something over, and your vertebra are the joints that allow you to turn.


On This Day in Math - October 28

   




"Big Fleas have little fleas upon their backs to bite 'em,

and little fleas have lesser fleas,

and so ad infinitum.

~Augustus De Morgan

The 301st day of the year; 301 is the sum of three consecutive primes starting at 97

\( 301 \equiv 1 Mod _b \) for every base,b, from 2 through 6   (Sixth grade version, if you divide 301 by any number 2 through 6, you get a remainder of 1)

301, like every odd number, is the difference of two consecutive squares, 151^2 - 150^2 .  It is also 25^2 - 18^2  (students should expand (x+7)^2 - x^2 to see why, and when this type of relation will next be useful.  




EVENTS

1386 Opening of the University of Heidelberg. It is the oldest university in Germany and was the third university established in the Holy Roman Empire. *Wik


1462 Archbishop Adolph of Nassau captured the city of Maintz and allowed his soldiers to plunder the city. This forced Gutenberg and his printers to flee, but rather than nipping printing in the bud, it forced its spread to Strasburg, Cologne, Basel, Augsburg, Ulm, Nuremberg, Subiaco, and by 1470, Paris. [G. H. Putnam, Books and Their Makers During the Middle Ages (1896),
p. 372]. *VFR


1636 Harvard College founded. The only mathematical master’s thesis in the U.S. before 1700 was at Harvard. This was in 1693 when the candidate took the affirmative position on “Is the quadrature of a circle possible?”. *VFR  The University web site has, "On September 8, 1636, Harvard, the first college in the American colonies, was founded. Who founded Harvard? Despite popular opinion (and a certain statue) John Harvard did not found Harvard, but he was the first major benefactor and he donated half of his estate and his library of more than 400 books to the School.(Read again, but keep in mind they had Masters candidates affirming the impossible, so math was not their best subject.)




1752  Euler writes to (?Goldbach?)  to say that he only knows of seven perfect numbers, those of the form \( (2^p -1)(2^{p-1}) \) with p = 2, 3, 5, 7, 13, 17, and 19.  He also says he is uncertain whether \(2^{31} - 1\) is prime (it is), and adds that if it has a factor , it will be of the form 64n+1. Numbers of the form \( 2^p -1|\) are called Mersenne primes, and as of Jan 2020, there were only 51 known.  *L E Dickson, History of the Theory of Numbers  *GIMPS   (On Oct 21, 2024 the addition of a new largest known Mersenne prime brings the total known to 52.  The new (and surely only temporary) largest known Mersenne Prime is 

2136,279,841 − 1.





1752 Euler publishes a paper listing the 161 numbers less than 15,000 for which \( n^2+1 \) is a prime. He also listed eight numbers for which \( n^4 + 1 \) is a prime; {1, 2, 4, 6, 16, 20, 24, and 34}.
He had described to Goldbach as early as July 9, 1743 a manor by which numbers of this form might be divisible.   *L. E. Dickson, History of the Theory of Numbers




1886 The Statue of Liberty was dedicated on Bedloe’s Island in New York Harbor. The sculptur Bartholin was present. The statue had almost been moved to another city when there was not enough interest in New York to pay the cost of building the pedestal.  Joseph Pulitzer, publisher of the World, a New York newspaper, announced a drive to raise $100,000 (the equivalent of $2.3 million today). Pulitzer pledged to print the name of every contributor, no matter how small the amount given.The drive captured the imagination of New Yorkers, especially when Pulitzer began publishing the notes he received from contributors. "A young girl alone in the world" donated "60 cents, the result of self denial."  As the donations flooded in, the committee resumed work on the pedestal. After five months of daily calls to donate to the statue fund, on August 11, 1885, the World announced that $102,000 had been raised from 120,000 donors, and that 80 percent of the total had been received in sums of less than one dollar.  *Wik

In this period when we need to remember that all Americans are immigrants, perhaps the second half of the plaque from  Emma Lazarus's  "The New Colossus"

"Keep, ancient lands, your storied pomp!" cries she

With silent lips. "Give me your tired, your poor,

Your huddled masses yearning to breathe free,

The wretched refuse of your teeming shore.

Send these, the homeless, tempest-tost to me,

I lift my lamp beside the golden door!"



(Hard to imagine some politicians today reading these words, sad. )





1899 Robert Goddard has a "Cherry Tree Dream" of space flight. He will forever remember this as his "anniversary day.:
He became interested in space when he read H. G. Wells' science fiction classic The War of the Worlds when he was 16 years old. His dedication to pursuing space flight became fixed on October 19, 1899. The 17-year-old Goddard climbed a cherry tree to cut off dead limbs. He was transfixed by the sky, and his imagination grew. He later wrote:

On this day I climbed a tall cherry tree at the back of the barn … and as I looked toward the fields at the east, I imagined how wonderful it would be to make some device which had even the possibility of ascending to Mars, and how it would look on a small scale, if sent up from the meadow at my feet. I have several photographs of the tree, taken since, with the little ladder I made to climb it, leaning against it.

It seemed to me then that a weight whirling around a horizontal shaft, moving more rapidly above than below, could furnish lift by virtue of the greater centrifugal force at the top of the path.

I was a different boy when I descended the tree from when I ascended. Existence at last seemed very purposive.


For the rest of his life he observed October 19 as "Anniversary Day", a private commemoration of the day of his greatest inspiration. *Wik




1938 The Indianapolis Star newspaper carried a story of a new proof of the Pythagorean Theorem by Ann Condit, a Junior at Central High School in South Bend, Ind.  Her proof is unique in that it used the midpoint of the hypotenuse is the origin of all auxiliary lines and triangles.  

In less than two years her proof would appear in Elisha Scott Loomis' 2nd edition of his  The Pythagorean Proposition, expanded to 344 proofs from the 230 proofs in his first edition. *David Acheson, The Wonder Book of Geometry
There seems to be little record of her adult life available, but sadly, I believe she died on March 4, 1969 at 47 years of age.  My thanks if anyone can supply nore information about her life.  


I believe this is her construction: 




On this day in 1952, Charles Coulson delivered his inaugural lecture as Rouse Ball Professor of Mathematics at the University of Oxford on The spirit of applied mathematics.
The Rouse Ball Professorship of Mathematics is one of the senior chairs in the Mathematics Departments at the University of Cambridge and the University of Oxford. The two positions were founded in 1927 by a bequest from the mathematician W. W. Rouse Ball. At Cambridge, this bequest was made with the "hope (but not making it in any way a condition) that it might be found practicable for such Professor or Reader to include in his or her lectures and treatment historical and philosophical aspects of the subject.
The current holders of the position (2023) are  Wendelin Werner[ at Cambridge and  Luis Fernando Alday at Oxford

W W Rouse Ball

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1957 Only three weeks after Sputnik went into space, young Denis Cox in Victoria, Australia sent a design for a spaceship addressed, "TO A TOP SCIENTIST AT Woomera ROCKET RANGE South Australia."  His design included locations for Australian Insignia, four Rolls Royce Engines, guided missiles, etc, but advised the scientists, "YOU PUT IN OTHER DETAILS".  
On September 24, 2009, an article on ABC Australia's web page indicated that "The Defence Science Technology Organisation is now finally organizing a letter from rocket scientists in response to the letter."


In 1965, the Gateway Arch (630' (190m) high) was completed in St. Louis, Missouri. This graceful sweeping tapered curve of stainless steel is the tallest memorial in the U.S. The architect of the catenary curve arch (correct children, it is NOT a parabola) was Eero Saarinen who won the design competition in 1947. It was constructed 1961-66 in the Jefferson National Expansion Memorial Park, established on the banks of the Mississippi River, on 21 Dec 1935, to commemorate the westward growth of the United States between 1803 and 1890. Cost for the $30 million national monument was shared by the federal government and the City of St. Louis. The memorial arch has an observation room at the top for visitors reached by trams running inside the legs of the arch.*TIS
The connection between Thomas Jefferson as the president who made the Louisiana Purchase and who created the English term Catenary should not go un-noted.  





BIRTHS


1703 Antoine Deparcieux (28 Oct 1703 in Clotet-de-Cessous, France - 2 Sept 1768 in Paris, France) was a French mathematician who is best known for an early work on annuities and mortality.*SAU

Among his constructions were:

A machine to raise water at Crécy castle
A pump for castle of Arnouville
A press for the production of tobacco
He also published many works, including:

Traité de trigonométrie rectiligne et sphérique (1738), approved by the Academy of Sciences
Nouveau traité de trigonométrie, (avec table des sinus et logarithmes) (1740)
Traité complet de Gnomonique (1741)
Essai sur les probabilités de la durée de la vie humaine (1746) ("Essay on the probabilities of the human lifespan"), which is the work for which he is best known[1]
Mémoire sur la courbure des ondes (1747)
In 1758, Deparcieux was elected a foreign member of the Royal Swedish Academy of Sciences.*Wik






1804 Pierre François Verhulst (28 October 1804, Brussels, Belgium – 15 February 1849, Brussels, Belgium) was a mathematician and a doctor in number theory from the University of Ghent in 1825. Verhulst published in 1838 the equation:

\( \frac{dN}{dt} = r N (1-\frac{N}{k}) \)

when N(t) represents number of individuals at time t, r the intrinsic growth rate and k is the carrying capacity, or the maximum number of individuals that the environment can support. In a paper published in 1845 he called the solution to this the logistic function, and the equation is now called the logistic equation. This model was rediscovered in 1920 by Raymond Pearl and Lowell Reed, who promoted its wide and indiscriminate use.*Wik




1845 Ulisse Dini (14 Nov 1845 in Pisa, Italy - 28 Oct 1918 in Pisa, Italy) Dini looked at infinite series and generalised results such as a theorem of Kummer and one of Riemann, the ideas for which had first emerged in work of Dirichlet. He discovered a condition, now known as the Dini condition, ensuring the convergence of a Fourier series in terms of the convergence of a definite integral. As well as trigonometric series, Dini studied results on potential theory. *SAU




1880 Michele Cipolla (born 28 October 1880 in Palermo; died 7 September 1947 in Palermo) was an Italian mathematician, mainly specializing in number theory.
He was a professor of Algebraic Analysis at the University of Catania and, later, the University of Palermo. He developed (among other things) a theory for sequences of sets and Cipolla's algorithm for finding square roots modulo a prime number. He also solved the problem of binomial congruence.*Wik



1937 Dr. Marcian Edward (Ted) Hoff, Jr. was born October 28, 1937 at Rochester, New York. He received a BEE (1958) from Rensselear Polytechnic Institute in Troy, NY. During the summers away from college he worked for General Railway Signal Company in Rochester where he made developments that produced his first two patents. He attended Stanford as a National Science Foundation Fellow and received a MS (1959) and Ph.D. (1962) in electrical engineering. He joined Intel in 1962. In 1980, he was named the first Intel Fellow, the highest technical position in the company. He spent a brief time as VP for Technology with Atari in the early 1980s and is currently VP and Chief Technical Officer with Teklicon, Inc. Other honors include the Stuart Ballantine Medal from the Franklin Institute.*CHM



1955 Bill Gates, cofounder and CEO of Microsoft Corporation, was born. Gates developed a version of BASIC for the Altair 8800 while being a student at Harvard. With the success of BASIC, he and co-developer Paul Allen​ founded Microsoft, which delivered an operating system for the IBM PC​, the Microsoft Word​ word processing program, the Window system software, and other programs. *CHM





DEATHS

1703 John Wallis (23 Nov 1616, 28 Oct 1703) British mathematician who introduced the infinity math symbol. Wallis was skilled in cryptography and decoded Royalist messages for the Parliamentarians during the Civil War. Subsequently, he was appointed to the Savilian Chair of geometry at Oxford in 1649, a position he held until his death more than 50 years later. Wallis was part of a group interested in natural and experimental science which became the Royal Society, so Wallis is a founder member of the Royal Society and one of its first Fellows. Wallis contributed substantially to the origins of calculus and was the most influential English mathematician before Newton. *TIS
Between 1643 and 1689 he served as chief cryptographer for Parliament and, later, the royal court. He is credited with introducing the symbol ∞ to represent the concept of infinity. 




1916 Cleveland Abbe (3 Dec 1838, 28 Oct 1916) U.S. astronomer and first meteorologist, born in New York City, the "father of the U.S. Weather Bureau," which was later renamed the National Weather Service. Abbe inaugurated a private weather reporting and warning service at Cincinnati. His weather reports or bulletins began to be issued on Sept. 1, 1869. The Weather Service of the United States was authorized by Congress on 9 Feb 1870, and placed under the direction of the Signal Service. Abbe was the only person in the country who was already experienced in drawing weather maps from telegraphic reports and forecasting from them. Naturally, he was offered an important position in this new service which he accepted, beginning 3 Jan 1871, and was often the official forecaster of the weather.*TIS



1918 Edward Bouchet (15 Sept 1852, New Haven, Conn – 28 Oct 1918, New Haven, Conn) was the first African-American to earn a Ph.D. in Physics from an American university and the first African-American to graduate from Yale University in 1874. He completed his dissertation in Yale's Ph.D. program in 1876 becoming the first African-American to receive a Ph.D. (in any subject). His area of study was Physics. Bouchet was also the first African-American to be elected to Phi Beta Kappa.
Bouchet was also among 20 Americans (of any race) to receive a Ph.D. in physics and was the sixth to earn a Ph. D. in physics from Yale.
When Bouchet was born there were only three schools in New Haven open to black children. Bouchet was enrolled in the Artisan Street Colored School with only one teacher, who nurtured Bouchet's academic abilities. He attended the New Haven High School from 1866–1868 and then Hopkins School from 1868-1870 where he was named valedictorian (after graduating first in his class).
Bouchet was unable to find a university teaching position after college, most likely due racial discrimination. Bouchet moved to Philadelphia in 1876 and took a position at the Institute for Colored Youth (ICY). He taught physics and chemistry at the ICY for 26 years. The ICY was later renamed Cheyney University. He resigned in 1902 at the height of the W. E. B. Du Bois-Booker T. Washington controversy over the need for an industrial vs. collegiate education for blacks.
Bouchet spent the next 14 years holding a variety of jobs around the country. Between 1905 and 1908, Bouchet was director of academics at St. Paul's Normal and Industrial School in Lawrenceville, Virginia (presently, St. Paul's College). He was then principal and teacher at Lincoln High School in Gallipolis, Ohio from 1908 to 1913. He joined the faculty of Bishop College in Marshall, Texas in 1913. Illness finally forced him to retire in 1916 and he moved back to New Haven. He died there, in his childhood home, in 1918, at age of 66. He had never married and had no children.*Wik




1965 Luther Pfahler Eisenhart (13 January 1876 – 28 October 1965) was an American mathematician, best known today for his contributions to semi-Riemannian geometry.
Eisenhart was born in York, Pennsylvania, and graduated from Gettysburg College in 1896. He earned his doctorate in 1900 at Johns Hopkins University, where he was influenced (at long range) by the work of Gaston Darboux and at shorter range by that of Thomas Craig. During the next two decades, Eisenhart's research focused on moving frames after the French school, but around 1921 took a different turn when he became enamored of the mathematical challenges and entrancing beauty of a new theory of gravitation, Albert Einstein's general theory of relativity.

Eisenhart played a central role in American mathematics in the early twentieth century. He served as chairman of the mathematics department at Princeton University and later as Dean of the Graduate School there from 1933 to 1945. He is widely credited with guiding the development in America of the mathematical background needed for the further development of general relativity, through his influential textbooks and his personal interaction with Albert Einstein, Oswald Veblen, and John von Neumann at the nearby Institute for Advanced Study, as well as with gifted students such as Abraham Haskel Taub.*Wik
 




1983 Pol(idore) Swings, (24 Sep 1906; 28 Oct, 1983) Belgian astrophysicist, made spectroscopic studies to identify elements and structure of stars and comets. He discovered the first interstellar molecule, the CH radical (1937). In comet atmospheres he studied the "Swings bands" - certain carbon emission lines. In 1941, with a slit spectrograph he identified a "Swings effect" in the violet CN bands (3875 A) - a fluorescence partly due to solar radiation that shows emmission line excitation differences dependant on the Doppler shift caused by a comet's motion relative to the Sun. He co-authored an Atlas of Cometary Spectra with Leo Haser in 1956. *TIS



1986 Irving Reiner (February 8, 1924, Brooklyn, New York – October 28, 1986) mathematician at the University of Illinois who worked on representation theory. He solved the problem of finding which abelian groups have a finite number of indecomposable modules. His book with Charles W. Curtis, (Curtis & Reiner 1962), was for many years the standard text on representation theory.*Wik




1988 John Backus (3 Dec 1924, 28 Oct 1988) American computer scientist who invented the FORTRAN (FORmula TRANslation) programming language in the mid 1950s. He had previously developed an assembly language for IBM's 701 computer when he suggested the development of a compiler and higher level language for the IBM 704. As the first high-level computer programming language, FORTRAN was able to convert standard mathematical formulas and expressions into the binary code used by computers. Thus a non-specialist could write a program in familiar words and symbols, and different computers could use programs generated in the same language. This paved the way for other computer languages such as COBOL, ALGOL and BASIC. *TIS




1989 Louise Schmir Hay (June 14, 1935 – October 28, 1989) was a French-born American mathematician. Her work focused on recursively enumerable sets and computational complexity theory, which was influential with both Soviet and US mathematicians in the 1970s. When she was appointed head of the mathematics department at the University of Illinois at Chicago, she was the only woman to head a math department at a major research university in her era.

Her work was influential with both Soviet and US mathematicians of the period. She co-founded the Association for Women in Mathematics (AWM) in an effort to provide support to other working mothers. In 1978, she won a Fulbright Scholarship, as did her husband, and they spent the year studying in the Philippines. In 1979, Hay was named the acting head of the University of Illinois' mathematics department. n 1980, she was appointed to the executive board of the AWM and remained in that post until 1987. She was also named as secretary of the Association for Symbolic Logic in 1982.



2003  Marie Maynard Daly (April 16, 1921 – October 28, 2003) American biochemist who was the first African-American woman to receive a Ph.D. in Chemistry (1947). Her postdoctoral research at the Rockefeller Institute included studying the composition and metabolism of components of cell nuclei, determining the base composition of deoxypentose nucleic acids, and calculating the rate of uptake of labeled glycine by components of cell nuclei. Seven years later, she took a university position. She taught biochemistry and researched the metabolism of the arterial wall and its relationship to aging, hypertension, and atherosclerosis. Later, she studied the uptake, synthesis, and distribution of creatine in cell cultures and tissues. She retired in 1986. *TIS 
 In 1953, Watson and Crick described the structure of DNA. Accepting the Nobel Prize for this work in 1962, Watson cited one of Daly's papers on "The role of ribonucleoprotein in protein synthesis" as contributing to his work. *Wik 





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