Tuesday, 9 June 2026

Regular Polygons Inscribed in a Similar Regular Polygon

  


A long time back, I wrote about some geometric options for a problem I had found on Greg Ross' Futility Closet. Shortly afterward I got a note from a blogger at "Five Triangles" who mentioned he had posted a very similar problem (above) about a year earlier.

What I especially enjoyed about his presentation of the problem was the obvious invitation to generalize the idea to regular polygons of more sides.
Each of the figures is simplified by the visual approach of rotating the inner polygon until it has its vertices at the midpoints of the sides of the larger. From there it is almost trivial that for the triangles, the smaller is 1/4 the larger (the logo of the five-triangles web site shows this clearly), and the smaller square is 1/2 the larger.(top image)

When you go to five sides the quick visual solutions disappear, but a generalization should offer itself to a clever trig student. If we assume the sides of the larger n-gon are each of unit length, then the area of the two polygons should be in the same ratio as the square of the side of the smaller polygon..... ( some were confused by this, the area of two similar polygons are in the ratio of the square of their corresponding side, but since we et the larger at one unit, its square is 1 square unit, and so the ratio of the two area is the square of the inner edge length over one.)....and a clever trig student looking at all those triangles (such as the blue FGB) formed between the two polygons should know a quick rule for finding the square of the side lengths of the inner polygon.... the beautiful extension of the Pythagorean theorem they know as the law of cosines.


Since each leg on the outside of the triangle is \(\frac{1}{2}\) unit, and the angle is \(\frac{\pi(n-2)}{n}\) it should be easy to determine that the square of the sides of the inner polygon is \(\frac {1}{2})^2 + (\frac {1}{2})^2 - 2 *(\frac {1}{2}*\frac {1}{2} * \cos(\frac{\pi(n-2)}{n})\) Or more simply, \(\frac {1}{2}(1-\cos(\frac{\pi(n-2)}{n}))\)
For values from n= 3 to 12 I came up with the following with the support of Wolframalpha:


Only the triangle, square, and hexagons produced rational roots, in convenient consecutive quarters for easy remembering.  The decimal approximations clearly support the intuitive idea that the limit should approach one as n grows larger without bound. By the time you get to the hectogon, the ratio is ,9990.  Fans of the "golden ratio will appreciate its appearance in the pentagon even if slightly camouflaged.

N      Ratio
3 ..... 0.25
4 ..... 0.5
5 ..... 0.654508
6 ..... 0.75
7 ..... 0.811745
8 ..... 0.853553
9 ..... 0.883022 
10 .... 0.904508
11 .... 0.920627
12 .... 0.933013
 
An interesting exploration, I think, for good trig students to explore.  Enjoy
 

On This Day in Math - June 9

  

The Boat House, Paducah, Ky


I've been giving this lecture to first-year classes
for over twenty-five years. 
You'd think they would begin to understand it by now.
~ J E Littlewood




The 160th day of the year; 160 is the smallest number which is sum of cubes of 3 distinct primes, the first three. (23+33+53) *Prime Curios (It is also the sum of the first power of the first 11 primes )

160! - 159! + 158! - ... -3! + 2! - 1! is prime.

160 is also the sum of two non-zero squares (122 + 42) and like all such numbers, you can show that 1602n+1 will also be the sum of two non-zero squares.

160 is the longest edge of the integer Heronian tetrahedron with smallest possible surface area and volume.  Its edges are 25, 39, 56, 120, 153, and 160; for a total surface area of 6384, and volume 8064.

Another Heronian triangle






160 is the largest year day (and second largest known) for which the alternating factorial sequence is prime: 160!- 159! + 158! - 157! .... + 2! - 1!. The alternating factorial 5! - 4! + 3! - 2! + 1! = 121. The alternating factorial sequence is prime for n= 3 through 8 (5, 19, 101, 619, 4421, 35899). In spite of this run of consecutive primes, John D Cook checked and found only 15 n values for which the alternating factorial starting with n is prime (There are now at least 17 known primes). 14 are year days, the largest being 160. 


More info on these here 
Find more math facts for each year day here


EVENTS

1750 Euler finally was able to prove the pentagonal theorem on June 9, 1750, in a letter to Goldbach. His proof is algebraic. The proof was first published in 1760, and Euler gives more details about points which were vague in his letter to Goldbach.
Euler had mentioned the theorem many times in the years following his first correspondence with Daniel Bernoulli (January 28,1741), in letters to Niklaus Bernoulli, Christian Goldbach, d’Alembert, and others, and in the first publication of 1751. (This paper was written on April 6, 1741 and had no proof. Euler wrote so many papers that the publishers fell dramatically behind; they were publishing new papers many years after his death.) A typical entry, from a letter to Goldbach, reads “If these factors \((1 − n)(1 − n^2)(1 − n^3) etc. are multiplied out onto infinity, the following series \(1 − n − n^2 + n^5 + n^7− etc is produced. I have however not yet found a method by which I could prove the identity of these two expressions. The Hr. Prof. Niklaus Bernoulli has also been able to prove nothing beyond induction.” Here the word “induction” means “by experiment” rather than “a proof by induction”. *Dick Koch, The Pentagonal Theorem and All That




1795 a provisional meter bar was constructed in brass by Lenoir. On 1 Aug 1793, the metre had been defined to be 1/10 000 000 of the northern quadrant of the Paris meridian (5 132 430 toises of Paris, from the north pole to the equator). On 7 Apr 1795, the first legal definition of the metre was made by the French National Assembly. A second measure was made along the Dunkirk-Barcelona axis (5 130 740 toises of Paris).
Closeup of National Prototype Metre Bar No. 27, made in 1889 by the International Bureau of Weights and Measures (BIPM) and given to the United States, which served as the standard for defining all units of length in the US from 1893 to 1960.  (the distance between two lines on a standard bar of an alloy of platinum with 10% iridium, measured at the melting point of ice) *Wik






1798 Napoleon’s fleet of 500 ships arrived in Malta, and three days later they captured the place. Monge started fifteen elementary schools and one high school there.*VFR

1905  Albert Einstein published his analysis of Planck's quantum theory and its application to light. His article appeared in Annalen der Physik. Though no experimental work was involved, it was for these insights that Einstein earned his Nobel Prize. *TIS
 Einstein quickly realized that Planck’s hypothesis about the quantization of radiant energy could also explain the photoelectric effect. Einstein used Planck's concept of the quantization of energy to explain the photoelectric effect, the ejection of electrons from certain metals when exposed to light. Einstein postulated the existence of what today we call photons, particles of light with a particular energy, E = hν.





1934 First Donald Duck Cartoon. Amazingly, the "Donald in Mathland" videos that were popular in the eighties in middle schools are still for sell.


BIRTHS

1669 Leonty Filippovich Magnitsky (9 June 1669 in Ostashkov, Russia - 30 October 1739 in Moscow, Russia) Peter the Great, Tsar of Russia, founded the School of Mathematics and Navigation in Moscow in 1701. Russia was a major power at this time but had no access to the sea. Peter decided that he would push north to try to dislodge the Swedes who controlled the Baltic coast and war had begun on this front in 1700. The many reforms, including the start of secular education, which Peter introduced to modernize Russia aimed to ensure victory in his wars for access to the seas. The declaration setting up the Moscow School was dated 14 January 1701, but formal classes did not begin immediately. There was a delay since facilities were not properly in place to allow teaching to begin. Peter the Great then appointed Magnitskii to the School on 2 February
In February, Magnitskii was appointed to the school and simultaneously ordered to compile a book "in the Slavonic dialect, selected from arithmetic, geometry and navigation." The 'Arithmetic' was therefore specifically commissioned to be the textbook of the Moscow School. Little is known about the classes in the school while the book was being prepared. It was sent to the publisher on 2 November 1702, and appeared bearing the date 11 January 1703. With its appearance the success of the school was assured.
The 'Arithmetic' was the first mathematics textbook published in Russia by a Russian which was not a translation or adaptation of a foreign textbook. It was a textbook for the courses which Magnitskii himself taught at the school, essentially a published version of his lecture notes. It was in effect an encyclopaedia of the mathematical sciences of its day, based strongly on applications in navigational astronomy, geodesy and navigation. It used the methods of algebra, geometry, and trigonometry. The 'Arithmetic',remained the basic Russian mathematics textbook for 50 years. *SAU




1812 Johann Gottfried Galle (9 June 1812 – 10 July 1910) German astronomer who on 23 Sep 1846, was the first to observe the planet Neptune, whose existence had been predicted in the calculations of Leverrier. Leverrier had written to Galle asking him to search for the 'new planet' at a predicted location. Galle was then a member of the staff of the Berlin Observatory and had discovered three comets. In 1838, while assistant to Johann Franz Encke, Galle discovered the dark, inner C ring of Saturn at the time of the maxium ring opening. In 1851, he became professor of astronomy at Breslau and director of the observatory there. In 1872, he proposed the use of asteroids rather than regular planets for determinations of the solar parallax, a suggestion which was successful in an international campaign (1888-89).




1885 John Edensor Littlewood born. (9 June 1885 – 6 September 1977) Littlewood’s Miscellany (1986) is a delightful little book, for it shows a mathematician having fun.*VFR
He collaborated for many years with G. H. Hardy. Together they devised the first Hardy–Littlewood conjecture, a strong form of the twin prime conjecture, and the second Hardy–Littlewood conjecture.
In a 1947 lecture, the Danish mathematician Harald Bohr said, "To illustrate to what extent Hardy and Littlewood in the course of the years came to be considered as the leaders of recent English mathematical research, I may report what an excellent colleague once jokingly said: 'Nowadays, there are only three really great English mathematicians: Hardy, Littlewood, and Hardy–Littlewood.'"
There is a story (related in the Miscellany) that at a conference Littlewood met a German mathematician who said he was most interested to discover that Littlewood really existed, as he had always assumed that Littlewood was a name used by Hardy for lesser work which he did not want to put out under his own name; Littlewood apparently roared with laughter. There are versions of this story involving both Norbert Wiener and Edmund Landau, who, it is claimed, "so doubted the existence of Littlewood that he made a special trip to Great Britain to see the man with his own eyes"*Wik




1906 Albert Cyril Offord FRS FRSE (9 June 1906 – 4 June 2000) was a British mathematician. He was the first professor of mathematics at the London School of Economics.
 He was educated at Hackney Downs Grammar School. He then studied Mathematics at University College, London. He then went to St John's College, Cambridge as a postgraduate, working with Prof John Edensor Littlewood.

He received two Ph.D.s in mathematics: the first from the University of London (under Bosanquet) in 1932, the second from Cambridge (under Hardy) in 1936.

In 1940 he left Cambridge to lecture at University College, Bangor. In 1942 he moved to King's College, Newcastle-upon-Tyne (later being named the University of Newcastle). He was created Professor of Mathematics in 1945.

In 1946 he was elected a Fellow of the Royal Society of Edinburgh. His proposers were Sir Edmund Whittaker, John William Heslop-Harrison, Alexander Aitken and Alfred Dennis Hobson. He was elected a Fellow of the Royal Society of London in 1952.

In 1948 he left Newcastle to become Professor of Mathematics at Birkbeck College in London replacing Prof Dienes. He left in 1966 to take up a new chair at London School of Economics. He retired in 1973 then becoming a senior research fellow at Imperial College, London.

He died in Oxford on 4 June 2000.



1909  Wade Ellis (June 9, 1909 – November 20, 1989) was an American mathematician and educator. He taught at Fort Valley State University in Georgia and Fisk University in Nashville, Tennessee and earned his Ph.D. in mathematics from the University of Michigan in 1944. He carried out classified research on radar antennas at the MIT Lincoln Laboratory and taught at Boston University and Oberlin College, where he became Full Professor in 1953. The same year, he was elected to the Board of Governors of the Mathematical Association of America.

Ellis promoted mathematical education and was decorated for his efforts in 1966 by the government of Peru. He returned to the University of Michigan in 1967 as Associate Dean of the Graduate School and Professor of Mathematics until his retirement in 1977, when he was named professor emeritus. Afterwards, he served in various administrative positions including vice chancellor of academic affairs at University of Maryland Eastern Shore and interim president of Marygrove College in Detroit.




1913 Muriel Kennett Wales (9 Jun 1913 – 8 August 2009) was an Irish-Canadian mathematician, and is believed to have been the first Irish-born woman to earn a PhD in pure mathematics.  [Some hold out for  Siobhan O’Shea (married name Vernon, born and reared in Macroom, Cork), who in 1964 received her PhD from University College Cork - – National University of Ireland, Cork, for a thesis consisting of previously published papers in analysis  ].

Muriel Wales  was first educated at the University of British Columbia (BA 1934, MA 1937 with the thesis Determination of Bases for Certain Quartic Number Fields). In 1941 she was awarded the PhD from the University of Toronto for the dissertation Theory Of Algebraic Functions Based On The Use Of Cycles under Samuel Beatty  (himself the first person to receive a PhD in mathematics in Canada, in 1915).

She spent most of the 1940s working in atomic energy, in Toronto and Montreal, but by 1949 had retired back to Vancouver where she worked in her step-father's shipping company.*Wik





1960  Carlo W. J. Beenakker (born June 9, 1960) is a professor at Leiden University and leader of the university's mesoscopic physics group, established in 1992. In 1997, he was awarded the Spinoza Prize, the "Dutch Nobel prize". *Wik
In 1993, he shared the Royal/Shell prize for "the discovery and explanation of quantum effects in the electrical conduction in mesoscopic systems". He was elected a member of the Royal Holland Society of Sciences and Humanities in 2001, and the Royal Netherlands Academy of Arts and Sciences in 2002. He was awarded one of the Netherlands' most prestigious science awards, the Spinozapremie, in 1999. In 2006 he was honored with the AkzoNobel Science Award "for his pioneering work in the field of nanoscience". He was granted an honorary doctorate from the Bogolyubov Institute for Theoretical Physics of the National Academy of Sciences of Ukraine. Beenakker is a Fellow of the American Association for the Advancement of Science and of the American Physical Society and a Knight of the Order of the Netherlands Lion. *Wik




1983 June E Huh ( June 9, 1983,  ) is an American mathematician who is currently a professor at Princeton University. Previously, he was a professor at Stanford University. He was awarded the Fields Medal and a MacArthur Fellowship in 2022. He has been noted for the linkages that he has found between algebraic geometry and combinatorics.
Huh was born in Stanford, California while his parents were completing graduate school at Stanford University. He was raised in South Korea, where his family returned when he was approximately two years old. His father was a professor of statistics at Korea University, while his mother was a professor of Russian language at Seoul National University. Poor scores on elementary school tests convinced him that he lacked the innate aptitude to excel in mathematics. He later dropped out of high school to focus on writing poetry after becoming bored and exhausted by the constant routine of relentless studying. Huh has been described as a late bloomer, both in terms of his career phenomena and with regards to his academic and professional development. Huh matriculated at Seoul National University in 2002, but found himself initially unsettled and suffering from depression. He pinned his initial career aspirations on becoming a science journalist and decided to major in physics and astronomy, but compiled a poor attendance record and had to repeat several courses that he initially failed at.
Early in his studies he was mentored by Japanese award-winning mathematician Heisuke Hironaka, who went to Seoul National University as a visiting professor. Having failed several courses, Huh took an algebraic geometry course under Hironaka in his sixth year which focused on singularity theory and was based on Hironaka's current research rather than established teaching material. Huh credited the course with sparking his interest in research-level math. Huh then proceeded to complete a master's degree at Seoul National University, while frequently travelling to Japan with Hironaka and acting as his personal assistant.[6] Due to his poor academic record as an undergraduate, Huh was rejected from all but one of the American universities that he applied to. He started his Ph.D. studies at the University of Illinois Urbana-Champaign in 2009, before transferring to the University of Michigan in 2011. He graduated in 2014 with a thesis written under the direction of Mircea Mustață at the age of 31. He was awarded the Sumner Byron Myers Prize for his PhD thesis.
Huh is married to Kim Nayoung, whom he met during his studies while attending Seoul National University. Kim is a graduate of Seoul National University where she earned her doctorate in mathematics. The couple has two sons.






DEATHS


1751 John Machin
 (bapt. 1686?—June 9, 1751) was an English mathematician and astronomer best known for the formulas he invented for calculating π.*VFR
He was a professor of astronomy at Gresham College, London, and is best known for developing a quickly converging series for Pi in 1706 and using it to compute Pi to 100 decimal places.
Machin's formula is:
\frac{\pi}{4} = 4 \cot^{-1}5 - \cot^{-1}239
The benefit of the new formula, a variation on the Gregory/Leibniz series (Pi/4 = arctan 1), was that it had a significantly increased rate of convergence, which made it a much more practical method of calculation.
To compute Pi to 100 decimal places, he combined his formula with the Taylor series expansion for the inverse tangent. (Brook Taylor was Machin's contemporary in Cambridge University.) Machin's formula remained the primary tool of Pi-hunters for centuries (well into the computer era).*Wik "This formula of John Machin (1680–1751) was publicized by William Jones in his 1706 Synopsis palmariorum matheseos. Variations of it remained the standard method for calculating τ/2 (pi) until the 1970s, when better methods due to Ramanujan came to light." *Theorem of the Day




1786 William George Horner (9 June 1786 – 22 September 1837) was a British mathematician. Proficient in classics and mathematics, he was a schoolmaster, headmaster and schoolkeeper who wrote extensively on functional equations, number theory and approximation theory, but also on optics. His contribution to approximation theory is honoured in the designation Horner's method, in particular respect of a paper in Philosophical Transactions of the Royal Society of London for 1819. The modern invention of the zoetrope, under the name Daedaleum in 1834, has been attributed to him.

Horner died comparatively young, before the establishment of specialist, regular scientific periodicals. So, the way others have written about him has tended to diverge, sometimes markedly, from his own prolific, if dispersed, record of publications and the contemporary reception of them.
Horner's name first appears in the list of solvers of the mathematical problems in The Ladies' Diary: or, Woman's Almanack for 1811, continuing in the successive annual issues until that for 1817. Up until the issue for 1816, he is listed as solving all but a few of the fifteen problems each year; several of his answers were printed, along with two problems he proposed. He also contributed to other departments of the Diary, not without distinction, reflecting the fact that he was known to be an all-rounder, competent in the classics as well as in mathematics. Horner was ever vigilant in his reading, as shown by his characteristic return to the Diary for 1821 in a discussion of the Prize Problem, where he reminds readers of an item in (Thomson's) Annals of Philosophy for 1817; several other problems in the Diary that year were solved by his youngest brother, Joseph.

Although Horner's article on the Dædalum (zoetrope) appeared in Philosophical Magazine only in January, 1834, he had published on Camera lucida as early as August, 1815.
In mathematics and computer science, Horner's method (or Horner's scheme) is an algorithm for polynomial evaluation. Although named after William George Horner, this method is much older, as it has been attributed to Joseph-Louis Lagrange by Horner himself, and can be traced back many hundreds of years to Chinese and Persian mathematicians. After the introduction of computers, this algorithm became fundamental for computing efficiently with polynomials.







1818 Joel E. Hendricks, (March 10, 1818 - June 9, 1893) a noted mathematician, was born in Bucks County, Pennsylvania, March 10, 1818. He early developed a love of mathematics and began to teach school at nineteen years of age. He chanced to procure Moore's Navigation and Ostrander's Astronomy and, without instruction, soon became able to work in trigonometry and calculate solar and lunar eclipses. He took up algebra while teaching and soon became master of that science without instruction. He taught mathematics two years in Neville Academy, Ohio, and then occupied a position on a Government survey in Colorado in 1861. In 1864 he located in Des Moines, Iowa and pursued his mathematical studies. In 1874 he began the publication of the Analyst, a journal of pure and applied mathematics and soon won a reputation in Europe among eminent scholars as one of the most advanced mathematicians of the day. His Analyst was taken by the colleges and universities of Europe and found a place in the best foreign libraries. His name became famous among all mathematical experts of the world. Among his correspondents were Benjamin Silliman, John W. Draper and James D. Dana; while his journal was authority at Yale and Johns Hopkins Universities. For ten years, up to 1884, this world-famous Analyst was published at Des Moines by Dr. Joel E. Hendricks. Up to the time it was discontinued, no journal of mathematics had been published so long in America." [Hendricks made arrangements to have it taken over by new management, and it was continued from March 1884 as the Annals of Mathematics.]

It is one of the remarkable events of the Nineteenth Century that a self-educated man should, by his own genius and industry, without instruction, reach such an exalted place among the world's great scholars. Dr. Hendricks died in Des Moines on the 9th of June, 1893. *History of Iowa From the Earliest Times to the Beginning of the Twentieth Century/Volume 4 by Benjamin F. Gue
A more complete mathematical biography of Mr. Hendricks can be found in The American Mathematical Monthly, Vol 1, #3, 1894.





1847 John Hailstone (13 Dec, 1759– 9 June, 1847), English geologist, born near London, was placed at an early age under the care of a maternal uncle at York, and was sent to Beverley school in the East Riding. Samuel Hailstone was a younger brother. John went to Cambridge, entering first at Catharine Hall, and afterwards at Trinity College, and was second wrangler and second in the Smith Prize of his year (1782). He was second in both competitions to James Wood who became master of Saint Johns, and Dean of Ely. Hailstone was elected fellow of Trinity in 1784, and four years later became Woodwardian Professor of Geology, an office which he held for thirty years.
He went to Germany, and studied geology under Werner at Freiburg for about twelve months. On his return to Cambridge he devoted himself to the study and collection of geological specimens, but did not deliver any lectures. He published, however, in 1792, ‘A Plan of a course of lectures.’
He married, and retired to the vicarage of Trumpington, near Cambridge, in 1818, and worked zealously for the education of the poor of his parish. He devoted much attention to chemistry and mineralogy, as well as to his favourite science, and kept for many years a meteorological diary. He made additions to the Woodwardian Museum, and left manuscript journals of his travels at home and abroad, and much correspondence on geological subjects. He was elected to the Linnean Society in 1800, and to the Royal Society in 1801, and was one of the original members of the Geological Society. Hailstone contributed papers to the ‘Transactions of the Geological Society’ (1816, iii. 243–50), the ‘Transactions of the Cambridge Philosophical Society’ (1822, i. 453–8), and the British Association (Report, 1834, p. 569). He died at Trumpington in his eighty-eighth year. *Wik




1897 Alvan Graham Clark (July 10, 1832 – June 9, 1897) U.S. astronomer, one of an American family of telescope makers and astronomers who supplied unexcelled lenses to many observatories in the U.S. and Europe during the heyday of the refracting telescope. He began a deep interest in astronomy while still at school, then joined the family firm of Alvan Clark & Sons, makers of astronomical lenses. In 1861, testing a new lens, he looked through it at Sirius and observed faintly beside it, Sirius B, the twin star predicted by Friedrich Bessel in 1844. Carrying on the family business, after the deaths of his father and brother, Clark made the 40" lenses of the Yerkes telescope (still the largest refractor in operation in the world). Their safe delivery was a source of anxiety. He died shortly after their first use.




1969 Harold Davenport (30 October 1907 – 9 June 1969) worked on number theory, in particular the geometry of numbers, Diophantine approximation and the analytic theory of numbers. He wrote a number of important textbooks and monographs including The higher arithmetic (1952)*SAU

While most sources credit Richard von Mises with creating the "Birthday Problem", I have found sources that credit Harold Davenport with creating the problem,.





1977 Dr. Gustav Doetsch (November 29, 1892 – June 9, 1977) was a German mathematician, aviation researcher, decorated war veteran, and Nazi supporter. The modern formation and permanent structure of the Laplace transform is found in Doetsch's 1937 work Theorie und Anwendung der Laplace-Transformation,[5] which was well-received internationally. He dedicated most of his research and scientific activity to the Laplace transform, and his books on the subject became standard texts throughout the world, translated into several languages. His texts were the first to apply the Laplace transform to engineering. *Wik




1994 Jan Tinbergen (April 12, 1903 – June 9, 1994), was a Dutch economist. He was awarded the first Bank of Sweden Prize in Economic Sciences in Memory of Alfred Nobel in 1969, which he shared with Ragnar Frisch for having developed and applied dynamic models for the analysis of economic processes. Tinbergen was a founding trustee of Economists for Peace and Security.
Tinbergen became known for his 'Tinbergen Norm', which is the principle that, if the difference between the least and greatest income in a company exceeds a rate of 1:5, that will not help the company and may be counterproductive.*Wik



1995  Vivienne Lucille Malone-Mayes (February 10, 1932 – June 9, 1995) was an American mathematician and professor. Malone-Mayes studied properties of functions, as well as methods of teaching mathematics. She was the fifth African-American woman to gain a PhD in mathematics in the United States, and the first African-American member of the faculty of Baylor University (which had rejected her application to study there five years earlier).
She decided to attend the University of Texas full-time as a graduate student when rejected entry at Baylor. In graduate school she was very much alone. In her first class, she was the only Black, the only woman. Her classmates ignored her completely, even terminating conversations if she came within earshot. She was denied a teaching assistantship, although she was an experienced and excellent teacher.
She wrote, "... it took a faith in scholarship almost beyond measure to endure the stress of earning a Ph.D. degree as a Black, female graduate student. I could not join my advisor and other classmates to discuss mathematics over coffee at Hilsberg's cafe .... Hilsberg's would not serve Blacks.
Some classes were closed to her despite the fact that the University of Texas was required to take Black students. For example R L Moore refused to have any Black students in his classes.
She was a member of the board of directors of the National Association of Mathematicians. She was elected Director-at-large for the Texas section of Mathematical Association of America and served as director of the High School Lecture Program for the Texas section.
She had a successful, lengthy career and served on several boards and committees of note, retiring in 1994 due to ill health.  She was the fifth African-American woman to be allowed in the White House.She was also active in her local community as a lifetime member of New Hope Baptist Church. She served on boards of directors for Cerebral Palsy, Goodwill Industries, and Family Counseling and Children. She was on the Texas State Advisory Council for Construction of Community Mental Health Centers and served on the board of the Heart of Texas Region Mental Health and Mental Retardation Center.
After Lillian K. Bradley in 1960, Malone-Mayes became one of the first African-American women to receive a PhD in Mathematics from University of Texas (and fifth African-American woman in the United States). She was the first African-American member of the faculty at Baylor University, and the first African-American person elected to Executive Committee of the Association of Women in Mathematics.
The student congress of Baylor voted her the "Outstanding Faculty Member of the Year" in 1971.  *Wik & *SAU

*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

Monday, 8 June 2026

On This Day in Math - June 8

 


If you open a mathematics paper at random, 
on the pair of pages before you, you will find a mistake.
~Joseph Doob


The 159th day of the year; 159 = 3 x 53, and upon concatenating these factors in order we have a peak palindrome, 353, which is itself a prime.*Prime Curios

159 is the sum of 3 consecutive prime numbers: 47 + 53 + 59 and can be written as the difference of two squares in two different ways.


Deshouillers (1973) showed that all integers are the sum of at most 159 prime numbers. I'm waiting for someone to tell me the number that takes 159 prime numbers to form??? 


 48 x 159 = 5346, uses all nine non-zero digits

159 is the fifth Woodall number, a number of the form n*2n -1.  The numbers were first studied by Allan J. C. Cunningham and H. J. Woodall in 1917, inspired by James Cullen's earlier study of the similarly-defined Cullen numbers (n*2n +1. )




EVENTS

1612 Paolo Gualdo wrote from Padua to say that Sagredo had sent him Galileo's letter on sunspots, which he had shown to many of his friends. *Stillman Drake, Galileo at Work

1637 The printing of Descartes’ Discours de la Methode, with its important appendix “La G´eom´etrie,” was completed. *VFR In 1637, the book Discourse on Method of Rightly Conducting the Reason, and Seeking Truth in the Sciences, was published by René Descartes, regarded as a major work in science and mathematics. He expresses his disappointment with traditional philosophy and with the limitations of theology; only logic, geometry and algebra hold his respect, because of the utter certainty which they can offer. Ushering in the "scientific revolution" of Galileo and Newton, Descartes' ideas swept aside ancient and medieval traditions of philosophical methods and investigation. *TIS
*Wik


1724 Euler received his master’s degree in philosophy at age 17, giving a lecture comparing the philosophical ideas of Descartes and Newton. His bachelor’s speech, in the summer of 1722, was “On temperance.” *VFR  Graduation with the same degree on that day was Johann II (Jean) Bernouli, only 14. *Ronald S. Calinger; Leonhard Euler: Mathematical Genius in the Enlightenment




1887 Herman Hollerith receives a patent for his punch card calculator. * The Geek Manual (I wonder what age is the lower  threshold for recognition of the term "punch card" as a computer term.)


1911  The Aero Club of America issued its first pilot licenses to five established aviators. Presented alphabetically, Glenn Curtiss received license #1. Orville and Wilbur Wright held licenses #4 and #5 behind U.S. Army pilot Frank Lahm (#2) and French aviator Louis Paulhan (#3). Subsequent pilots had to pass a flight test to earn a license.
Thirty-six-year-old Harriet Quimby became the first female licensed pilot in the U.S. on August 1, 1911, when she earned license #37 from the Aero Club of America. She became a prize-winning pilot at air meets and was the first woman to fly across the English Channel in April 1912. Like many aviators of her generation, Quimby’s life was cut short when she died in a plane crash near Boston on July 1, 1912.


*Linda Hall Org



In 1918, Nova Aquila, the brightest nova since Kepler's nova of 1604, was discovered in the constellation of Aquila the eagle, a 1st magnitude star 6 degrees north of the Scutum star cloud. For the months that it shone, it was the brightest star in the sky, briefly half a million times brighter than the sun, but seen from 1200 light years (70,000 trillion miles) away. Between 1899 and 1936 there were 20 fairly bright novae, and five of those were in this same small area of the sky, the constellation Aquila. Seven years later Nova Aquila had faded to a bluish star apparently much smaller and denser than our sun. (Aquila belonged to Zeus, and was the eagle that carried the mortal Ganymede to the heavens to serve as Zeus' cup bearer.)TIS





1918 The total solar eclipse of June 8, 1918 crossed the United States from Washington State to Florida. This path is roughly similar to the August 21, 2017 total solar eclipse and was the last time totality crossed the nation from the Pacific to the Atlantic. *greatamericaneclipse.com

1921 Edith Clarke submits patent for the Clark Calculator. The calculator was 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. Ms. Clarke is generally thought of as the first female electrical engineer in the U. S.

1923 Art historian Joan Evans speaks on “Jewels of the Renaissance”, and becomes the first woman to give a Discourse at the Ri. *Royal Institution web page,    
She was a British historian of French and English mediaeval art, especially Early Modern and medieval jewelry. Her notable collection was bequeathed to the Victoria and Albert Museum in London *Wik


1948 Carl Savit, a graduate student at Caltech, appeared in court to demand $1000 from Mottant Company of Chicago for solving the three classical construction problems. This offer was made in an advertisement that neglected to require that compass and straightedge be used. It is not known if he collected. [Mathematics Magazine 61 (1988), p 158].*VFR There are are many beautiful approaches to trisecting a general angle using other tools as I wrote in "Trisecting the General Angle, A Plethora of Pretty Approaches"

1979 The Source, the first computer public information service, goes on line.

2004 The second most recent (most recent was in 2012) transit of Venus when observed from Earth took place on June 8, 2004. The event received significant attention, since it was the first Venus transit to take place after the invention of broadcast media. No human alive at the time had witnessed a previous Venus transit, since the previous Venus transit took place on December 6, 1882. The next transit of Venus occurred on June 5–June 6 in 2012,. If you missed these two, the next transits of Venus will be in December 2117 and December 2125.*Wik




BIRTHS

1625 Jean Dominique Cassini (June 8, 1625, Perinaldo - September 14, 1712, Paris)
Italian-born French astronomer who in 1675 discovered Cassini's division, the dark gap subdividing Saturn's rings into two parts. 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
The pinhole-projected image of the Sun on the floor at Florence Cathedral. Jean Cassini measured a similar image over a year at San Petronio Basilica to try to prove the Earth orbited the Sun.






1724 John Smeaton (8 June 1724 – 28 October 1792)  English civil engineer, who coined the term "civil engineering" (to distinguish from military engineers). He built the third Eddystone Lighthouse, Plymouth, Devon, using dovetailed blocks of portland stone (1756-59). He discovered the best mortar for underwater construction to be limestone with a high proportion of clay. Smeaton also constructed the Forth and Clyde Canal in Scotland between the Atlantic and the North Sea; built bridges in towns including Perth, Banff, and Coldstream, Scotland; and completed Ramsgate harbour, Kent. He introduced cast-iron shafts and gearing into wind and water mills, designed large atmospheric pumping engines for mines, and improved the safety of the diving bell.)*TIS





1725 Caspar Wessel(June 8, 1745, Vestby – March 25, 1818, Copenhagen)  was a Norwegian mathematician who invented a geometric way of representing complex numbers which pre-dated Argand. *SAU
His fundamental paper, Om directionens analytiske betegning, was published in 1799 by the Royal Danish Academy of Sciences and Letters. Since it was in Danish, it passed almost unnoticed, and the same results were later independently found by Argand and Gauss.
One of the more prominent ideas presented in "On the Analytical Representation of Direction" was that of vectors. Even though this wasn't Wessel's main intention with the publication, he felt that a geometrical concept of numbers, with length and direction, was needed. Wessel's approach on addition was: "Two straight lines are added if we unite them in such a way that the second line begins where the first one ends and then pass a straight line from the first to the last point of the united lines. This line is the sum of the united lines". This is the same idea as used today when summing vectors. Wessel's priority to the idea of a complex number as a point in the complex plane is today universally recognized. His paper was re-issued in French translation in 1899, and in English in 1999 as On the analytic representation of direction (ed. J. Lützen et al.).*Wik




1858 Charlotte Agnas Scott (8 June 1858 – 10 November 1931, Cambridge) born in Lincoln, England. She attended Girton, the first (1869) college in England for women. In 1880 she took the tripos exam at Cambridge, but because she was a woman, her name could not be announced at the award ceremony. “The man read out the names and when he came to ‘eighth,’ before he could say the name, all the undergraduates called out ‘Scott of Girton,’ and cheered tremendously, shouting her name over and over again with tremendous cheers and waving of hats.” [Women of Mathematics. A Biobibliographic Sourcebook (1987), edited by Louise S. Grinstein and Paul J. Campbell] *VFR




1860 Alicia Boole Stott  (June 8, 1860, Cork, Ireland – December 17, 1940, England) was the third daughter of George Boole. (Read more about Boole's descendents in my blog, "Those Amazing Boole Girls." ) George Boole died when Alicia was only four years old and she was was brought up partly in England by her grandmother,(Mary Everest Boole was a mathematician educator who was an early advocate of teaching children math through playful activities. It is almost certain she would have exposed her daughters to such activities {pb}) partly in Cork by her great-uncle. When she was twelve years old she went to London where she joined her mother and sisters.
With no formal education she surprised everyone when, at the age of eighteen, she was introduced to a set of little wooden cubes by her brother-in-law Charles Howard Hinton. Alicia Boole experimented with the cubes and soon developed an amazing feel for four dimensional geometry. She introduced the word 'polytope' to describe a four dimensional convex solid.

*Wik
MacHale, writes:-
She found that there were exactly six regular polytopes on four dimensions and that they are bounded by 5, 16 or 600 tetrahedra, 8 cubes, 24 octahedra or 120 dodecahedra. She then produced three-dimensional central cross-sections of all the six regular polytopes by purely Euclidean constructions and synthetic methods for the simple reason that she had never learned any analytic geometry. She made beautiful cardboard models of all these sections....
After taking up secretarial work near Liverpool in 1889 she met and married Walter Stott in 1890. Stott learned of Schoute's work on central sections of the regular polytopes in 1895 and Alicia Stott sent him photographs of her cardboard models. Schoute came to England and worked with Alicia Stott, persuading her to publish her results which she did in two papers published in Amsterdam in 1900 and 1910.
The University of Groningen honoured her by inviting her to attend the tercentenary celebrations of the university and awarding her an honorary doctorate in 1914.
In 1930 she was introduced to Coxeter and they worked together on various problems. Alicia Stott made two further important discoveries relating to constructions for polyhedra related to the golden section. *Wik

1867 Frank Lloyd Wright (June 8, 1867 – April 9, 1959) was born in Richland Center, Wisconsin. Widely regarded as America's most significant architect, Wright transformed twentieth-century
residential design; his influential Prairie School houses and plans for public buildings proved simultaneously innovative, aesthetically striking, and practical. A social visionary, Wright's commitment to a context-driven "organic architecture," which harmonized with both its occupants' needs and the surrounding landscape, underscored his creative genius across a long and productive career.*Library of Congress




1870 Peter Pinkerton (8 June 1870 in Kilmarnock, Scotland -22 November 1930 in Glasgow, Scotland) studied at Glasgow and Dublin. After teaching at various schools he became Rector of Glasgow High School. He became President of the EMS in 1908. *SAU

1896 Eleanor Pairman (June 8, 1896-September 14, 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.*SAU
Shw was the third woman to receive a doctorate in math from Radcliffe College in Massachusetts. Later in life she developed novel methods to teach mathematics to blind students. 
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."




1905 Edward Hubert Linfoot (8 June 1905, Sheffield, England - 14 October 1982, Cambridge, England)
After attending King Edward VII School he won a scholarship to Balliol College at the University of Oxford.
During his time at Oxford he met the number theorist G. H. Hardy, and after graduating in 1926, Linfoot completed a D.Phil under the supervision of Hardy with a thesis entitled Applications of the Theory of Functions of a Complex Variable.
After brief stints at the University of Göttingen, Princeton University, and Balliol College, Linfoot took a job in 1932 as assistant lecturer, and later lecturer, at the University of Bristol. During the 1930s Linfoot's interests slowly made the transition from pure mathematics to the application of mathematics to the study of optics, but not before proving an important result in number theory with Hans Heilbronn, that there are at most ten imaginary quadratic number fields with class number 1 *WIK




1915  José Luis Massera (Genoa, Italy, June 8, 1915 – Montevideo, September 9, 2002) was a Uruguayan dissident and mathematician who researched the stability of differential equations.

Massera's lemma is named after him. He published over 40 papers during 1940–1970. A militant Communist, he was a political prisoner during 1975–1984. In the 1930s, Julio Rey Pastor gave regular weekend lectures on topology in Montevideo to a group that included Massera. Stimulated by contact with Argentine mathematics, the 1950s saw Uruguay develop a fine school in mathematics, of which Massera was very much a part.

Massera developed new notions of stability, and published several foundational papers and an influential textbook. His results in (Massera 1950) on periodic differential equations have been heavily cited and are referred to as Massera's theorem. His work in (Massera 1949) and (Massera 1956) on the converse to Lyapunov's criterion is also influential, and contain the well known Massera's lemma. His textbook (Massera & Schäffer 1966) is also heavily cited.

After military intervention in Uruguay in 1973, Massera was arrested on October 22, 1975 in Montevideo and was held in solitary confinement for nearly a year. During this time he was subjected to repeated torture resulting in injuries including a fractured pelvis. In October 1976 he was taken from solitary confinement, tried and convicted for "subversive association", and given a 24-year prison sentence. On June 22, 1979, as a consequence of a proposal put forward by Gaetano Fichera and unanimously approved by the whole Mathematics Faculty Council of the Sapienza University of Rome, he was awarded the laurea honoris causa while still being under conviction. He was released in 1984. *Wik 
During his youth a revolution began in Uruguay he began looking up words in his fathers massive dictionary.  Looking up "equation" he found dozens of different types of equations and began to explore, and finding other terms in thos definition expanded his search.  On a trip with his father he found a huge bookstore in Paris and his father bought him a classical geometry book and a trigonometry which he "devoured in a short time."





1923 Gloria Olive (8 June 1923, New York City, USA - 17 April 2006, Dunedin, New Zealand)
Gloria Olive completed her school educations at Abraham Lincoln High School in Brooklyn, New York, graduating in 1940. She then entered Brooklyn College in New York where she studied mathematics, graduating with an B.A. in 1944. Perhaps the most famous of her lecturers was Jesse Douglas who had been awarded the Fields Medal at the International Congress of Mathematicians at Oslo in 1936. After graduating, Olive was appointed as a Graduate Assistant at the University of Wisconsin where she spent the two academic years 1944-46. In addition to teaching she studied for her Master's Degree during these two years and was awarded the degree in 1946.
From Wisconsin, Olive moved to the University of Arizona in 1946 where she was appointed as an instructor. After two years she was appointed to Idaho State University where again she spent two years teaching as an instructor. Her next appointment in Oregon State University in 1950 was as a Graduate Assistant and after this one-year post she left the academic world for a short time, taking a job as a cryptographer in the U.S. Department of Defense in Washington, D.C. After a year in Washington, Olive returned to an academic position being appointed to Anderson College in 1952.

Anderson Bible Training School had been founded in 1917 as an educational establishment to train leaders and workers for a life in the church. It rapidly developed a broader, more general, education program, and changed its name first to Anderson College and Theological Seminary, and then to Anderson College. At Anderson College, Olive built up the mathematics department and began to become interested in mathematical research, in particular studying generalised powers. C C MacDuffee, who had taught Olive at the University of Wisconsin, agreed to accept a visiting professorship at Oregon State University so that he could supervise her doctoral thesis. Sadly he died in 1961 and Olive was left without a thesis advisor. However she was awarded a Ph.D. for her thesis Generalized Powers in 1963.

Olive continued to at Anderson College until 1968 when she accepted a professorship at the University of Wisconsin-Superior. She stayed at the University of Wisconsin-Superior until 1972, the year after it joined the University of Wisconsin, and went to New Zealand where she was appointed as a senior lecturer at the University of Otago. She continued in this post until she retired in 1989. Mac Lane and Rayner wrote on her retirement
For all of her time with the Mathematics and Statistics Department of Otago University, Gloria has been the only female on the staff with tenure, and as such has been a shining example to both staff and students. She has fought hard for the issues she championed, and contributed to several worthwhile changes (such as the current internal assessment policy applauded by both staff and students). Her colleagues will miss her lively contributions to the debates in departmental meetings.
Much of Olive's research was on applications of generalised powers. She published papers such as Binomial functions and combinatorial mathematics (1979), A combinatorial approach to generalized powers (1980), Binomial functions with the Stirling property (1981), Some functions that count (1983), Taylor series revisited (1984), Catalan numbers revisited (1985), A special class of infinite matrices (1987), and The ballot problem revisited (1988). *SAU





1924 Samuel Karlin (June 8, 1924 - December 18, 2007) made fundamental contributions to game theory, analysis, mathematical statistics, total positivity, probability and stochastic processes, mathematical economics, inventory theory, population genetics, bioinformatics, and biomolecular sequence analysis, was born in Yonova, Poland, and immigrated to Chicago as a child. Karlin earned a doctorate in mathematics at age 22 from Princeton in 1947. He taught at Caltech from 1948 to 1956 before moving to Stanford as a Professor of Math and Stat. Overall, Karlin had over 70 PhD students, to whom he was an extraordinary teacher and advisor.(*David Bee)




2013 Gury Ivanovich Marchuk ( 8 June 1925 – 24 March 2013) was a Soviet and Russian scientist in the fields of computational mathematics, and physics of atmosphere. Academician (since 1968); the President of the USSR Academy of Sciences in 1986–1991. Among his notable prizes are the USSR State Prize (1979), Demidov Prize (2004), Lomonosov Gold Medal (2004).

Marchuk was born in Orenburg Oblast, Russia. A member of the Communist Party of the Soviet Union since 1947, Academician Marchuk was elected to the Central Committee of the Party as a candidate member in 1976 and as a full member in 1981. He was elected as deputy of the Supreme Soviet of the Union of Soviet Socialist Republics in 1979. He was appointed to succeed Vladimir Kirillin as chairman of the State Committee for Science and Technology (GKNT) in 1980.

Marchuk was a proponent of the Integrated Long-Term Programme (ILTP) of Cooperation in Science & Technology that was established in 1987 as a scientific cooperative venture between India and the Soviet Union. The programme allowed the scientists of the countries to collaboratively undertake research in areas as diverse as healthcare and lasers. Marchuk co-chaired the programme's Joint Council with Prof. C.N.R. Rao for 25 years and was made an honorary member of India's National Academy of Sciences. In 2002, the Government of India conferred the Padma Bhushan on him *Wik




1936 Kenneth Geddes "Ken" Wilson (June 8, 1936 – June 15, 2013) was an American physicist who was awarded the 1982 Nobel Prize for Physics for his development of a general procedure for constructing improved theories concerning the transformations of matter called continuous, or second-order, phase transitions. These take place at characteristic temperatures (or pressures), but unlike first-order transitions they occur throughout the entire volume of a material as soon as that temperature (called the critical point) is reached. One example of such a transition is the complete loss of ferromagnetic properties of certain metals when they are heated to their Curie points (about ºC for iron). Wilson's work provided a mathematical strategy for constructing theories that could apply to physical systems near the critical point. *TiS




1955 Tim Berners-Lee (8 June 1955- ), English computer scientist who invented the World Wide Web and director of the World Wide Web Consortium, which oversees its continued development. In 1984, he took up a fellowship at CERN, to work on distributed real-time systems for scientific data acquisition and system control. While there , in 1989, he proposed a global hypertext project, to be known as the World Wide Web, which permitted people to collaborate by sharing knowledge in a web of hypertext documents. On 6 Aug 1991, the first World Wide Web site was made available to the Internet at large, giving information on a browser and how to set up a Web server. He then expanded its reach, always nonprofit, to become an international mass medium. *TIS





DEATHS

1882 John Scott Russell (9 May 1808, Parkhead, Glasgow – 8 June 1882, Ventnor, Isle of Wight)  British civil engineer best known for researches in ship design. He designed the first seagoing battleship built entirely of iron. He was the first to record an observation of a soliton, while conducting experiments to determine the most efficient design for canal boats. In Aug 1834, he observed what he called the "Wave of Translation," a solitary wave formed in the narrow channel of a canal which continues ahead after a canal boat stops. [This is now recognised as a fundamental ingredient in the theory of 'solitons', applicable to a wide class of nonlinear partial differential equations.] He also made the first experimental observation of the "Doppler shift" of sound frequency as a train passes (1848). He designed (with Brunel) the Great Eastern and built it; he designed the Vienna Rotunda and helped to design Britain's first armored warship, the Warrior. *TIS




1883 Joel E. Hendricks, (March 10, 1818 - June 9, 1893) a noted mathematician, was born in Bucks County, Pennsylvania, March 10, 1818. He early developed a love of mathematics and began to teach school at nineteen years of age. He chanced to procure Moore's Navigation and Ostrander's Astronomy and, without instruction, soon became able to work in trigonometry and calculate solar and lunar eclipses. He took up algebra while teaching and soon became master of that science without instruction. He taught mathematics two years in Neville Academy, Ohio, and then occupied a position on a Government survey in Colorado in 1861. In 1864 he located in Des Moines, Iowa and pursued his mathematical studies. In 1874 he began the publication of the Analyst, a journal of pure and applied mathematics and soon won a reputation in Europe among eminent scholars as one of the most advanced mathematicians of the day. His Analyst was taken by the colleges and universities of Europe and found a place in the best foreign libraries. His name became famous among all mathematical experts of the world. Among his correspondents were Benjamin Silliman, John W. Draper and James D. Dana; while his journal was authority at Yale and Johns Hopkins Universities. For ten years, up to 1884, this world-famous Analyst was published at Des Moines by Dr. Joel E. Hendricks. Up to the time it was discontinued, no journal of mathematics had been published so long in America. It is one of the remarkable events of the Nineteenth Century that a self-educated man should, by his own genius and industry, without instruction, reach such an exalted place among the world's great scholars. Dr. Hendricks died in Des Moines on the 9th of June, 1893. *History of Iowa From the Earliest Times to the Beginning of the Twentieth Century/Volume 4 by Benjamin F. Gue

A more complete mathematical biography of Mr. Hendricks can be found in The American Mathematical Monthly, Vol 1, #3, 1894.








1920 Augusto Righi (27 August 1850 – 8 June 1920) was an Italian physicist and a pioneer in the study of electromagnetism. He was born and died in Bologna.
Righi was the first person to generate microwaves, and opened a whole new area of the electromagnetic spectrum to research and subsequent applications. His work L'ottica delle oscillazioni elettriche (1897), which summarised his results, is considered a classic of experimental electromagnetism. Marconi was his student. *Wik




1935 Alexander Wilhelm von Brill (20 September 1842 – 18 June 1935) was a German mathematician.
Cardboard 'Sliceforms' by John Sharp.
Born in Darmstadt, Hesse, Brill was educated at the University of Giessen, where he earned his doctorate under supervision of Alfred Clebsch. He held a chair at the University of Tübingen, where Max Planck was among his students. In 1933, he joined the National Socialist Teachers League as one
of the first members from Tübingen.
The London Science Museum contains sliceform objects prepared by Brill and Felix Klein. *Wik

1988 Roger Conant Lyndon (December 18, 1917 – June 8, 1988) was an American mathematician, for many years a professor at the University of Michigan.[1] He is known for Lyndon words, the Curtis–Hedlund–Lyndon theorem, Craig–Lyndon interpolation and the Lyndon–Hochschild–Serre spectral sequence.
Lyndon's Ph.D. thesis concerned group cohomology; the Lyndon–Hochschild–Serre spectral sequence, coming out of that work, relates a group's cohomology to the cohomologies of its normal subgroups and their quotient groups.
A Lyndon word is a nonempty string of symbols that is smaller, lexicographically, than any of its cyclic rotations; Lyndon introduced these words in 1954 while studying the bases of free groups.
Lyndon was credited by Gustav A. Hedlund for his role in the discovery of the Curtis–Hedlund–Lyndon theorem, a mathematical characterization of cellular automata in terms of continuous equivariant functions on shift spaces.
The Craig–Lyndon interpolation theorem in formal logic states that every logical implication can be factored into the composition of two implications, such that each nonlogical symbol in the middle formula of the composition is also used in both of the other two formulas. A version of the theorem was proved by William Craig in 1957, and strengthened by Lyndon in 1959.
In addition to these results, Lyndon made important contributions to combinatorial group theory, the study of groups in terms of their presentations in terms of sequences of generating elements that combine to form the group identity. *Wik




1998 Maria Reiche (May 15, 1903, Dresden -  June 8, 1998, Peru) German-born Peruvian mathematician and archaeologist who was the self-appointed keeper of the Nazca Lines, a series of desert ground drawings over
1,000 years old, near Nazcain in southern Peru. For 50 years the "Lady of the Lines" studied and protected these etchings of animals and geometric patterns in 60 km (35 mi) of desert. Protected by a lack of wind and rain, the figures are hundreds of feet long best seen from the air. She investigated the Nazca lines from a mathematical point of view. Death at age 95 interrupted her new mathematical calculations: the possibility that the lines predicted cyclical natural phenomena like El Nino, a weather system that for centuries has periodically caused disastrous flooding along the Peruvian coast.






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