Wednesday, 11 November 2026

More on Surprisingly Constant

    As I mentioned before, I'm re-posting some of the most popular blogs of recent years.  This one, "Surprisingly Constant" was from 2010, but I've added a bit at the end from the amazing graphics mathematical posts of "3Blue 1 Brown."

Some things never change... and some of the things that don’t change are pretty remarkable. I was recently reminded of two that always seemed non-intuitive, and therefore quite pleasing. Both of these can be proved toward the end of a first year calculus course, and at least one can be explained with a little hand-waving, by a good pre-calc student.

The first is the simple fact that if you take a slice a sphere with a pair of parallel planes that are some distance, d, apart; the surface area of the part of the sphere between those planes is the same no matter where the slices are made. Near the “poles” or near the “equator”, the area is the same. It is nice to be able to tell students that this incredibly interesting fact was known to Archimedes in the first Century of the modern era when he proved that the surface area of a sphere is the same as the lateral area of a cylinder that contains the sphere.

This image is part of an explanation provided at a math site at the University of Regina

The essence of the explanation uses nothing beyond similar triangles. If we approximate the sphere’s surface between the slicing planes as a frustum of a cone, then the slant height (AP) can be shown to be in the same proportion to the height (AB)as the radius of the frustum (QP) is to the radius of the sphere(KP)). This image is also from the U Regina site mentioned above.Another nice thing about this relation is that when you set up the rather fearsome looking integral for the surface area, it reduces through simple algebra to a constant.

For a different look at this with some beautiful graphics, as well as several nice explanations of why the formula for the surface area of a sphere is four times the area of a circle, see this 3Blue, 1Brown video on YouTube.




The second similarly interesting idea is about the volume of a shape I call a bead, for lack of a more precise term. The bead is the solid remaining when you drill through the center of a sphere.The unexpected constant here is that for any radius sphere you start with, the volume of the bead depends only on the height. And perhaps even less expected, is that the volume is the same as the volume of an un-drilled sphere with the same height (i.e., when 2r = h).

I have found a beautiful non-calculus proof of this using an idea from Mamikon Mnatsakanian work with his visual geometry.

On This Day in Math - November 11

   





The British Mathematical Colloquium consists of three days of mathematics
with no dogs and no wives.
~Henry Whitehead

The 315th day of the year; 3152 can be written as the sum of the cubes of five consecutive integers. Find them. (Students may also wish to find the smallest square that can be expressed as the sum of the cubes of two or more consecutive integers.)

315 = 3^2 x 5 x 7  (or 5 x 7 x 9)  In a variation of use of Vandermonde's (and others since) "rising factorials" and "falling factorials" I have adopted the symbol \(9!_(2}\)  for 9x7x5x3x1; and \(9!_(2,3}\) for 9 x 7 x 5.  stopping after three terms.   

315 is a (barely)deficient number, the sum of it's proper divisors is only 309 ...309/315 is about .9809 *Derek Orr @Derektionary  pointed out to me that 256 is the closet to one of any (non-perfect) year day, (255/256 = .996), and for non-powers of two, 136 with a ratio of 134/136 = .985 is the best.


EVENTS
1572 Tycho Brahe first observed a supernova in the constellation Cassiopeia. Cornelius Gemma, the son of Gemma Frisius, made the first recorded observation of it on 9 November. Cornelius, Tycho, and others all observed the nova and determined it to be superlunary, thereby signalling a change in the superlunar sphere contradicting Aristotelian cosmology. *RMAT
(Brahe was at the beginning of his career in 1572, and it was this supernova that inspired him to devote his lifetime to making accurate measurements of the positions of the stars and planets.) For two weeks it was brighter than any other star in the sky and visible in daytime. By month's end, it began to fade but it remained visible to the naked eye for about 16 months until Mar 1574. *TIS  



1619 During the night, while living in Neuberg on the Danube, Descartes had a dream that he was visited by the Angel of Truth who revealed to him that mathematics was the sole key needed to unlock the secrets of nature. *Sheldrake, The Presence of the Past: Morphic Resonance and the Habits of Nature
This dream is often cited as a pivotal moment in his philosophical and scientific development, solidifying his belief in the power of reason and mathematical logic to unravel the mysteries of nature.   *Google AI



1675 In a manuscript Leibniz struggled with the product and quotient rules for differentiation. At first he thought d(uv)= du dv.  *VFR  It would not be until the 21st that he completes the product rule. *F Cajori, History of Mathematics, (pg 208) Leibniz had previously used d twelve days earlier in the denominator, but in the margin he explains that dx is the same as his previous x/d, the difference of two neighboring x's.  Within a fortnight he had created the two basic symbols of calculus that have lasted for almost 350 years.



1744 in a letter of November 11, 1744, Cramer gave Euler a complete description of his rule for solving systems of linear equations. This is noteworthy, because Cramer's Rule would not appear in print until six years later, where it was an appendix in his very influential book “Introduction to the analysis of algebraic curves”.  Even more interesting is that the passage in Cramer's letter is virtually identical, word for word, to a three-page passage in the Introduction [Cramer 1750, pp. 657-659]. *VFR
*Wik


1844 Both the terms vector and scalar were introduced by William Rowan Hamilton (1805-1865). Both terms appear in "On quaternions" a paper presented by Hamilton at a meeting of the Royal Irish Academy on November 11, 1844. This paper adopts the convention of denoting a vector by a single (Greek) letter, and concludes with a discussion of formulae for applying rotations to vectors by conjugating with unit quaternions. *Jeff Miller, Earliest Known Uses of Some of the Words of Mathematics
The term vector, and radius vector had been used much earlier. OED gives the earliest use of "vector" in Astronomy, from a technical dictionary of 1704: J. Harris Lexicon Technicum I. s.v., "A Line supposed to be drawn from any Planet moving round a Center, or the Focus of an Ellipsis, to that Center or Focus, is by some Writers of the New Astronomy, called the Vector; because 'tis that Line by which the Planet seems to be carried round its Center." The term is drawn from the Latin for "to carry".



1912 Bragg's law was first presented by Lawrence Bragg to the Cambridge Philosophical Society. Bragg's law confirmed the existence of real particles at the atomic scale, as well as providing a powerful new tool for studying crystals in the form of X-ray and neutron diffraction. Lawrence Bragg and his father, William Henry Bragg, were awarded the Nobel Prize in physics in 1915 for their work in determining crystal structures beginning with NaCl, ZnS, and diamond. They are the only father-son team to jointly win. Lawrence Bragg was 25 years old, making him the youngest physics Nobel laureate. *Wik 
Bragg’s original notebook where he first wrote down his law for diffraction of X-rays. *

Prof Stuart Mangles@plasmaStu

 The work, titled "The Diffraction of Short Electromagnetic Waves by a Crystal," was subsequently published in the Proceedings of the Cambridge Philosophical Society in 1913.




1918 Armistice Day. At the eleventh hour of the eleventh day of the eleventh month World War I ended.*VFR

In 1925, the discovery of cosmic rays was announced in Madison, Wisconsin by Robert A. Millikan who coined their name.*TIS  After the discovery of radioactivity by Henri Becquerel in 1896, it was generally believed that atmospheric electricity, ionization of the air, was caused only by radiation from radioactive elements in the ground or the radioactive gases or isotopes of radon they produce. In 1909 Theodor Wulf developed an electrometer, a device to measure the rate of ion production inside a hermetically sealed container, and used it to show higher levels of radiation at the top of the Eiffel Tower than at its base. However, his paper published in Physikalische Zeitschrift was not widely accepted. In 1911 Domenico Pacini observed simultaneous variations of the rate of ionization over a lake, over the sea, and at a depth of 3 meters from the surface. Pacini concluded from the decrease of radioactivity underwater that a certain part of the ionization must be due to sources other than the radioactivity of the Earth. *Wik
Millikan's original oil-drop apparatus, circa 1909–1910, *Wik



1930  Albert Einstein and his colleague Leo Szilard designed a refrigerator that avoided the need for seals that could go bad. Instead of the mechanical pumps used in existing commercial refrigerators, the Einstein-Szilard refrigerator used an electromagnetic pump that required no moving parts. The two were motivated by contemporary newspaper reports of a Berlin family who had been killed when a seal in their refrigerator failed and leaked toxic fumes into their home. Einstein and Szilard received a US patent on November 11, 1930, for their invention.

Einstein had other patents such as an expandable blouse, an electrical sound system for hearing aids, and a self-focusing camera.

A much more interesting telling of this story, and many more, can be found in the book, Beer and thew Nobel Prize by  Thomas M. Annesley, Professor of Clinical Chemistry at The University of Michigan Medical School.





1945, Glenn T. Seaborg appeared as a guest on "Quiz Kids." One of the children on the show, Richard Williams, asked Seaborg if any new elements, in addition to plutonium and neptunium, had been discovered at the Metallurgical Laboratory in Chicago during the war. Since the discovery information had already been declassified for announcement at the forthcoming ACS national meeting on Nov. 16, Seaborg shared the news that two new elements (americium and curium) with atomic numbers 95 and 96 had been discovered.
Seaborg then told Williams, "So now you'll have to tell your teachers to change the 92 elements in your schoolbook to 96 elements." Seaborg later recalled in his 1979 Priestley Medal address that many kids did, in fact, tell their teachers to change the number of elements. "Judging from some of the letters I received from such youngsters, they were not entirely successful in convincing their teachers," he said.
*http://pubs.acs.org





1954 Algeria issued a stamp honoring Saint Augustine of Hippo (354–430). He is best remembered for his quote about mathematicians being in league with the devil. [Scott #261] *VFR  (The Quote, "Quapropter bono christiano, sive mathematici, sive quilibet impie divinantium, maxime dicentes vera, cavendi sunt, ne consortio daemoniorum animam deceptam, pacto quodam societatis irretiant." has been translated to "The good Christian should beware the mathematician and all those who make empty prophecies. The danger already exists that the mathematicians have made a covenant with the devil to darken the spirit and to confine man in the bonds of hell." Some suggest this is a mistranslation. The Latin word 'mathematici' derives from the Greek meaning of 'something learned' and refers mainly to astrologers. This was the chief branch of mathematics at the time but has been replaced in modern times by a plethora of other branches. According to the Shorter Oxford English Dictionary, 3rd edition, the word "mathematician" still meant astrologer as late as 1710.) *Wik




1979 Greg Maggs and Robert Kolstad complete the world’s longest slide rule. It is 323 feet long and 9.5 inches wide and is located in the University of Illinois College of Law building, Champaign.  The previous record, 320 feet 11.1 inches in length completed in March, 1979, by students of Alvirne High School, Hudson, New Hampshire. *Guinness  This record was broken in 2001 with a 350 feet 6.6 inch model. To my knowledge, this is currently the World's Longest documented Slide Rule, called The Texas Magnum by Skip Solberg and Jay Francis. It was demonstrated on February 28, 2001 in the Lockeed-Martin Aircraft Assembly Facility at Air Force Plant 4 in Fort Worth, Texas. The Texas Magnum was designed as a traditional Mannheim style slide rule. The A, C, D and L scales are included. *International Slide Rule Museum

A little over two decades later I ran across the smallest slide rule I have ever seen in an Antique shop in Cadiz, Ky.  It was a sterling silver tie clip with a working center bar and slide, two inches long.


  And on a tip from Ted Courant, I found these even smaller cuff link working slide rules, 1.125" long




1997 Proof by John Friedlander and Henryk Iwaniec that there are infinitely many prime numbers of the form m2 + n4, for positive integers m and n submitted to Proceedings of the National Academy of Sciences (USA) "Using a parity-sensitive sieve to count prime values of a polynomial." *Theorem of the Day

2015 In 1966 Chen Jingrun made a giant step toward a proof of Goldbach's conjecture when he stated Chen's Theorem: Every sufficiently large even number can be written as the sum of two primes, or a prime and a semi-prime. On November 11, 2015;  Tomohiro Yamada gave an explicit value for "sufficiently large" when he proved that Chen's theorem is true for all numbers greater than  approximately 17 (101872344071119348) *HT to John Cook







BIRTHS

1729 Birthdate of Louis Antoine de Bougainville.
 Although he began as a mathematician (under d’Alembert’s influence he wrote the first textbook on the integral calculus in 1752), he became famous as an explorer. He was the first Frenchman to sail around the world. But he was no great navigator, in spite of his mathematical ability. *VFR (The largest of the Solomon Islands is named after him, as is the colorful tropical climbing plant bougainvillaea. (see image at top))



1851 Adolphe-Louis Jacques Bertillon (11 Nov 1851 in Paris, France - 7 July 1922 in Valmondois, near Paris, France) Bertillon was a French statistician who applied statistics to social sciences. *SAU


1875 Vesto Melvin Slipher (11 Nov 1875; died 8 Nov 1969) American astronomer whose systematic observations (1912-25) of the extraordinary radial velocities of spiral galaxies provided the first evidence supporting the expanding-universe theory. Slipher spectroscopically measured the displacement of their spectral lines by the Doppler effect by which the wavelength of light from an object moving away from an observer will shifted toward the red end of the spectrum. Earlier, Slipher had determined the rotation periods of some of the planets by spectroscopic means. With Lowell (1912), he found Uranus had a  rotation period of  10.8 hours. He also produced comparable data for Venus, Mars, Jupiter, and Saturn and showed that Venus's period was much longer than expected. *TIS




1904 John Henry Constantine Whitehead (11 November 1904–8 May 1960), known as Henry, was a British mathematician and was one of the founders of homotopy theory. He was born in Chennai (then known as Madras), in India, and died in Princeton, New Jersey, in 1960. *Wik
Whitehead's work in differential geometry culminated in the paper "On the Covering of a Complete Space by the Geodesics Through a Point" (1935), containing pioneering contributions to this area of mathematics. He always retained his interest in geometry but soon focused on topology. He made substantial contributions to combinatorial homotopy and Stiefel manifolds and set up a school of topology at Oxford. *TIS One of his better quotes was, "It is the snobbishness of the young to suppose that a theorem is trivial because the proof is trivial."





1905 Sigekatu Kuroda (黒田 成勝, Kuroda Shigekatsu, 11 November 1905 – 3 November 1972) was a Japanese mathematician who worked in number theory and mathematical logic.
In 1942 he became a professor at the newly founded Nagoya Imperial University, where he stayed for over twenty years. He was responsible for much of the effort in setting up its Department of Mathematics.

He was married to the renowned number theorist Teiji Takagi's daughter Yakeo. The couple had three sons, all of whom became mathematicians, including S.-Y. Kuroda, who was a professor of linguistics at the University of California, San Diego.

He published a text on the foundations of algebraic number theory with Tomio Kubota in 1963.








1911 Caleb Gattegno (November 11, 1911; Alexandria, Egypt- July 28, 1988, Paris, France) was born in Alexandria, Egypt. He is best known for his innovative approaches to teaching and learning mathematics (Visible & Tangible Math). Creator of the Geoboard, and founder of the Cuisenaire Company which manufactures educational manipulatives. *Wik




1930 Hugh Everett III (November 11, 1930 – July 19, 1982) was an American physicist who first proposed the many-worlds interpretation (MWI) of quantum physics, which he termed his "relative state" formulation.
Discouraged by the scorn of other physicists for MWI, Everett ended his physics career after completing his Ph.D. Afterwards, he developed the use of generalized Lagrange multipliers for operations research and applied this commercially as a defense analyst and a consultant. He was married to Nancy Everett née Gore. They had two children: Elizabeth Everett and Mark Oliver Everett, who became frontman of the musical band Eels.





DEATHS




1938 Typhoid Mary
 (Mary Mallon) , (23 Sep 1869, 11 Nov 1938) famous typhoid carrier in the New York City area in the early 20th century. Fifty-one original cases of typhoid and three deaths were directly attributed to her (countless more were indirectly attributed), although she herself was immune to the typhoid bacillus (Salmonella typhi). The outbreak of Typhus in Oyster Bay, Long Island, in 1904 puzzled the scientists of the time because they thought they had wiped out the deadly disease. Mallon's case showed that a person could be a carrier without showing any outward signs of being sick, and it led to most of the Health Code laws on the books today. She died not from typhoid but from the effects of a paralytic stroke dating back to 25 Dec 1932. *TIS




1954 Horatio Carslaw (12 February 1870, Helensburgh, Dumbartonshire, Scotland – 11 November 1954, Burradoo, New South Wales, Australia) studied at Glasgow and Cambridge. He lectured at the University of Glasgow before moving to a professorship in Sydney, Australia. He worked on a variety of topics in both pure and applied mathematics. He co-authored  Conduction of Heat in Solids, which remains a classic in the field. *SAU






1967 Lester Randolph Ford, Sr. (October 25, 1886 – 11 November 1967) was an American mathematician, editor of the American Mathematical Monthly from 1942 to 1946, and President of the Mathematical Association of America from 1947 to 1948.
Ford circles are named after him.*Wik (Students, if you are not familiar with Ford Circles, and their rich beautiful history and interesting algebraic and geometric relations, look them up for an interesting exploration.  Start here)
He is the father of L. R. Ford Jr, who specializes in network flow problems.





1997  Menahem Max Schiffer (24 September 1911, Berlin – 11 November 1997)) was a German-born American mathematician who worked in complex analysis, partial differential equations, and mathematical physics.
Menachem Max Schiffer studied physics from 1930 at the University of Bonn and then at the Humboldt University of Berlin with Max von Laue, Erwin Schrödinger, Walter Nernst, Erhard Schmidt, Issai Schur and Ludwig Bieberbach. In Berlin he worked closely with Issai Schur. In 1934, after being forced by the Nazis to leave the academic world, he immigrated to Mandatory Palestine.

On the basis of his prior mathematical publications, Schiffer received a master's degree from the Hebrew University of Jerusalem. In 1938, he received his doctorate under the supervision of Michael Fekete. In his dissertation on Conformal representation and univalent functions he introduced the "Schiffer variation", a method for handling geometric problems in complex analysis.

In September 1952, he began to teach at Stanford University, along with George Pólya, Charles Loewner, Stefan Bergman, and Gábor Szegő.

With Paul Garabedian, Schiffer worked on the Bieberbach conjecture with a proof in 1955 of the special case n=4. He was a speaker at the International Congress of Mathematicians (ICM) in 1950 at Cambridge, Massachusetts, and was a plenary speaker at the ICM in 1958 at Edinburgh with plenary address Extremum Problems and Variational Methods in Conformal Mapping. In 1970 he was elected to the United States National Academy of Sciences. He retired from Stanford University as professor emeritus in 1977. *Wik



2003  Andrei Andreevich Bolibrukh  (30 January 1950 – 11 November 2003) was a Soviet and Russian mathematician. He was known for his work on ordinary differential equations especially Hilbert's twenty-first problem (Riemann–Hilbert problem). Bolibrukh was the author of about a hundred research articles on theory of ordinary differential equations including Riemann–Hilbert problem and Fuchsian system.

 After receiving his mathematical education at the Lomonosov Moscow State University, with Mikhail Mikhailovich Postnikov and Alexey Chernavskii as thesis advisers, he started working on the proof of the existence of linear differential equations having a prescribed monodromic group. He applied modern methods of complex analytic geometry to classical problems about ordinary differential equations and was an expert on Hilbert's twenty-first problem. In 1989, Bolibrukh produced his famous counterexamples which invalidated the Josip Plemelj's 1908 solution of Hilbert's twenty-first problem. Bolibrukh dedicated much of his efforts to the Riemann-Hilbert problem in order to find full necessary and sufficient conditions for given monodromy data to be those of a Fuchsian system.

During his short career he served as Deputy Director of the Steklov Institute of Mathematics and professor at the Moscow Institute of Physics and Technology. *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

Tuesday, 10 November 2026

Lune, Lens and related terms.....Etymology and History of Math Terms

  Lune, Lens and related terms

The word lune is from Luna, the Roman Goddess of the Moon. The more ancient Indo-European root is leuk, which relates to light. Lunatic is from the same root, perhaps because the ancients believed it was the effects of the moon that accounted for the crazy behavior.
Lune is used in mathematics to describe two different ideas. [see figure below] The most common is the area on a sphere between two semicircles with endpoints at the same poles. Imagine two lines of longitude running from the North Pole to the South pole. The surface of the Earth between the two lines is called a lune. There is also a two dimensional shape called a lune. The crescent area formed between two excentric circles that share a common chord is also called a lune. This shape plays an important part in the mathematics of the ancient Greeks. The definition I have used is from "The Mechanic's Assistant: A Thorough Practical Treatise on Mensuration" by D. M. Knappen, published in 1849. The Wolfram Mathworld web site, which is usually one of the top sources for math topics defines the planer lune this way, "A lune is a plane figure bounded by two circular arcs of unequal radii, i.e., a crescent." These two definitions do NOT seem to be the same to me. Imagine the crescent formed by two excentric circles of the same radius. I wonder why this must be excluded from the Wolfram definition. Under either construction, there are two crescent regions formed. Students will not see many planer lunes in their math experience, but the ones they do seem almost all to be constructed so that the smaller radius circle has its center on the common chord of the two circles. I do not think this is a property of lunes in genral. To be sure, I asked the memebers of the Philomathes Yahoo discussion group, and Colin McLarty responded with, "Neither arc needs to have its center on the common chord, and Hippocrates did a case where neither one does. Since he was interested in squaring lunes, and he was so far as we know pretty much limited to Euclidean means, he necessarily dealt with only very special cases. It is unlikely he ever worried about a precise general definition of "lune" -- esp. whether or not the case of equal radii would qualify to be called a lune." [see a suggested definition from David W. Cantrell farther below]

A spherical lune is sometimes also called a digon, since it is a two-sided polygon (and less appropriately called a bigon since that mixes both Latin and Greek roots... and leads too often to the quip, "let bigons be bigons".)

The plane lune was studied in depth by the Greek mathematician Hippocrates of Chios (around 400 BC) in an attempt to find a way to find a square with the same area as a given circle using only the classic tools of compass and straightedge. He discovered that a lune formed by the chord which is the hypotenuse of a central right angle has an area equal to the area of the right triangle. This lune is still called the Lune of Hippocrates. Later he found two other plane lunes that could also be "squared". A nice site on the lunes which can be squared is here. The problem of "Squaring the Circle" was one of the three great unsolved problems of Greek mathematics. Much later it was proven using algebraic tools that the task was impossible, but the Greeks discovered lots of important mathematical ideas in their search to prove the impossible.

Hippocrates of Chios, the mathematician, is often confused with Hippocrates of Cos, who is considered to be the father of medicine, and for whom the Hippocratic Oath is named. This should not be two unexpected since they both lived at the same time, and came from relatively close islands off the coast of modern day turkey. This link shows a map of the area. There is an arrow pointing out the island of Cos, just northwest of Rhodes. North of Cos just south of Lesbos is the island of Chios. Between them is the Island of Samos, which was the birthplace of Pythagorus.

Two similar looking objects that may be included here are "lens" and "gibbous". The area of intersection between two circles is often called a lens, because it resembles a biconvex lens. The word lens actually is drawn from the word lentil, for its symmilarity to the lentil seed. Gibbous is derived from the Latin root for "hunchback" and can be applied to any object that is convex or rounded, but is most commonly used to describe the phases of the moon between a half-moon and a full-moon.

There is, or once was, a special name for the intersection between two identical circles and is called the Vesci Pescies. Here is a description from "Geometry in Art" by Hilton Andrade De Mello. "The 'Vesica Piscis' is an important symbol based on the circle. It is generated by the intersection of two identical circles, as shown in Figure 9.2 with one circle centered at point A and the other centered at point B. The area common to both circles, shown in blue, is called 'Vesica Piscis' because it resembles a vesicle, i.e., a receptacle. As seen later in this chapter, the “Piscis”, which is Latin for 'fish', is associated with the symbol adopted by early Christianity." Images below are from the e-text of the book.

 

David W. Cantrell suggested what I think are very clear definitions of lune and lens in a discussion on another list, and graciously sent me a copy: ”Given two circular disks, A and B, having a nonempty intersection and such that neither is entirely contained in the other, three regions are formed. (Think of a Venn diagram.) One of the regions, A intersect B, is convex; I suggest that "lens" be used to name that kind of shape. Neither of the other two regions, A-B and B-A, is convex; I suggest that "lune" be used to name that kind of shape. “

On This Day in Math - November 10

   

“Composição em Vermelho e Preto” - Aluisio Carvão - Oil on canvas

My work always tried to unite the true with the beautiful, but when I had to choose one or the other, I usually chose the beautiful.
~Herman Weyl

The 314th day of the year; 314 is the smallest number that can be written as the sum of 3 positive distinct squares in 6 ways. *What's Special about this number
(Students, can you find the smallest number that can be written as the sum of two distinct squares in at least two ways?)

314 = 5^2 + 17^2

314 is a semi-prime, and 3142 +1 is prime


EVENTS

In 1619, Descartes had enlisted in the army of the Duke of Bavaria. On 10 Nov 1619, at Neuberg on the Danube (presumably Neuberg, Bayern, about 20km west of Ingolstadt), he found the cold, which he never liked, so bad that he locked himself in a heated room and began his contemplations. He and others consider this the most significant date of his entire life and the birth date of analytic geometry! At the end of the winter, he continued his wanderings.


1664, Robert Hooke wrote to Robert Boyle about his experiment in which he had opened the chest of a living dog.
In his letter, he described how he ‘opened the thorax, and cut off all the ribs’ of the dog, and ‘handled…all the other parts of its body, as I pleased’. But despite these rather horrific details, we see through Hooke’s words a man deeply moved by the suffering he had caused, for he ends, ‘I shall hardly be induced to make any further trials of this kind, because of the torture of this creature’. What Hooke hadn’t realized before he began his experiment was that lungs were not muscles, and that by removing the animal’s chest, he had removed the dog’s ability to breathe on its own. To keep the animal alive, Hooke pushed a hollow cane down the dog’s throat and into its windpipe. He then pumped air into the animal’s lungs with a bellow for over an hour, carefully studying the way in which the organs expanded and contracted with each artificial breath. All-the-while, the dog stared at him in horror, unable to whimper or cry out in agony
*Lindsey Bracken, The Chirurgeon's Apprentice



1719 London gets a light show from the Aurora Borealis. Halley describes "An Account of the Phaenomena of a Very Extraordinary Aurora Borealis, Seen at London on November 10. 1719. Both Morning and Evening." By Dr. Edmond Halley. R.S. Secr. *Philosophical Transactions

1742 Euler writes to Niklaus I Bernoulli on November 10, 1742. This is the last letter in their correspondence that deals with the pentagonal number theorem. Euler writes: “This expression (1−n)(1−n2)(1−n3)(1−n4) etc. by expansion shall give the series 1−n−n2+n5+n7−etc . in which no other exponents occur unless they are contained in 3xx±x2

which I have for my part concluded with legitimate induction, even if I have not been able to find a demonstration in any manner, however, although I have notdevoted enough time to this





1872 Stanley found Livingstone. VFR

1885  The world's first motorcycle, designed by Gottlieb Daimler, made its first significant test-run. Daimler's 17-year-old son, Paul, travelled from Cannstatt to Unterturkheim and back. Their “Reitwagen” had a wooden frame and wheels. A leather drive belt ran between the engine and large brass gears on the rear wheel. With no suspension on the wheels, the leather saddle gave a very uncomfortable ride, at a speed up to 12 km/hr. The single cylinder engine had a bore of 58mm, stroke of 100mm and a displacement of 264cc's. The engine gave 0.5hp at 700 rpm. Two very much smaller, spring-mounted outrigger wheels provided some stability. This was built as an experimental vehicle to test the new Daimler engine in a proof of concept, which was to power Daimler's first motorized carriage the following year.*Tis 
did not continue making motorcycles because they built the Daimler Reitwagen strictly as a testbed for a new internal-combustion engine rather than as a commercial motorcycle.Daimler and Maybach shifted their primary focus to four-wheeled automobiles and larger motor vehicles.   Their successful engine designs soon powered carriages, boats, and cars, leading to the creation of Daimler-Motoren-Gesellschaft. [






1918 A marble monument to Niccolo Fontana known as Tartaglia
 (1499-1557) was unveiled at Brescia, his birthplace. *VFR



1957 GIGO first used in print? The Times Daily of Hammond, Indiana printed an article that opened : “BIZMAC UNIVAC, GARBAGE IN-GARBAGE OUT — all new terms in the Army… These colorful expressions are part of the working vocabulary of the military mathematicians who man the Army’s electronic computors [sic].” *Robert Stenson, Atlas Obscura


In 1983, U.S. student Fred Cohen presented to a security seminar the results of his test - the first documented virus, created as an experiment in computer security. Cohen created this first virus when studying for a PhD at the University of Southern California. Others had written about the potential for creating pernicious programs but he was the first to demonstrate a working example. In the paper, he defined a virus as "a program that can 'infect' other programs by modifying them to include a ... version of itself". Cohen added his virus to a graphics program called VD, written for a Vax mini-computer. The virus hid inside VD and used the permissions users had to look at other parts of the Vax computer to spread around the system.*TIS




1983 Microsoft announces a new product, Windows, to compete with other graphical environments for computers, such as interface on the Apple Lisa. After several delays, Windows 1.0 finally became available to the public in 1985. Its major features included pull-down menus, tiled windows, mouse support, and cooperative multitasking of the program’s applications. Although Windows 1.0 saw some use, the Windows interface did not gain general acceptance until version 3.0*CHM



1984 Evariste Galois was commemorated as a revolutionary and geometrician on a French postal stamp issued on 10 Nov 1984. He was born in the little village of Bourg-la-Reine, near Paris, France. He is remembered for his contributions to the part of higher algebra known as group theory. His theory solved many long-standing unanswered questions, including the impossibility of trisecting the angle and squaring the circle. *TIS

2015  "
While most people associate the mathematical constant π (pi) with arcs and circles, mathematicians are accustomed to seeing it in a variety of fields. But two University scientists were still surprised to find it lurking in a quantum mechanics formula for the energy states of the hydrogen atom.
“We didn’t just find pi,” said Tamar Friedmann, a visiting assistant professor of mathematics and a research associate of high energy physics, and co-author of a paper published this week in the Journal of Mathematical Physics. “We found the classic seventeenth century Wallis formula for pi, making us the first to derive it from physics, in general, and quantum mechanics, in particular.”
The Wallis formula—developed by British mathematician John Wallis in his book Arithmetica Infinitorum—defines π as the product of an infinite string of ratios made up of integers. For Friedmann, discovering the Wallis formula for π in a quantum mechanics formula for the hydrogen atom’s energy states underscores π’s omnipresence in math and science."  *News Center, University of Rochester  


2024  Serving fugu puffer fishes in Japan requires a special license because they contain a toxin as deadly as cyanide. In 2024 a 10-year-old became the youngest ever to receive the license. Karin Tabira,  A 10-year-old fifth-grader from the Kumamoto region of Japan was the one.  Out of 93 people who took the test—mostly adult professional chefs—only 60 passed, including Karin.  She trained for about six months starting in February 2024 at Fukunari, a local fugu-farming and wholesale company. She even had to stand on a platform to reach the kitchen counter and used a hammer to drive her knife through the fish's tough bones.
She used her new certification to prepare paper-thin fugu sashimi for the governor of Kumamoto, Takashi Kimura, who declared it "oishi" (delicious).
Between 2004 to 2023 Japan recorded 450 poisoning incidents but only 17 total deaths  *PB .






BIRTHS


1829 Elwin Bruno Christoffel (10 Nov 1829 in Montjoie Aachen (now Monschau), Germany - 15 March 1900 in Strasbourg, France) Christoffel published works on conformal mappings, Riemann's o-function, the theory of invariants, and the Christoffel reduction theorem.*SAU





1861 Robert Thorburn Ayton Innes (10 Nov 1861; 13 Mar 1933) was a Scottish astronomer who discovered Proxima Centauri (1915), the closest star to earth after the Sun. Invited by David Gill to the Cape Observatory, South Africa (1894), he became a successful binary star observer with the 7-inch refractor (1628 discoveries). His most famous discovery, Proxima Centauri is a faint star near the binary star Alpha Centauri, which is so far south it is not visible from most of the northern hemisphere. He was also the first to see the Daylight Comet of 1910, though this comet was found independently by so many people in the Southern Hemisphere that no single "original" discoverer could be named. Innes recorded it on 17 Jan 1910. *TIS




1896 Ernst Paul Heinz Prüfer (10 Nov 1896 in Wilhelmshaven, Germany
- 7 April 1934 in Münster, Germany) was a German mathematician who proved important results about abelian groups.*SAU



1902 Thomas Gerald Room FRS FAA (10 November 1902 – 2 April 1986) was an Australian mathematician who is best known for Room squares. He was a Foundation Fellow of the Australian Academy of Science.He studied mathematics in St John's College, Cambridge, and was a wrangler in 1923. He continued at Cambridge as a graduate student, and was elected as a fellow in 1925, but instead took a position at the University of Liverpool. He returned to Cambridge in 1927, at which time he completed his PhD, with a thesis supervised by H. F. Baker.  Room remained at Cambridge until 1935, when he moved to the University of Sydney, where he accepted the position of Chair of the Mathematics Department, a position he held until his retirement in 1968.
During World War II he worked for the Australian government, helping to decrypt Japanese communications.
Room's PhD work concerned generalizations of the Schläfli double six, a configuration formed by the 27 lines on a cubic algebraic surface.
In 1938 he published the book The geometry of determinantal loci through the Cambridge University Press. Nearly 500 pages long, the book combines methods of synthetic geometry and algebraic geometry to study higher-dimensional generalizations of quartic surfaces and cubic surfaces. It describes many infinite families of algebraic varieties, and individual varieties in these families, following a unifying principle that nearly all loci arising in algebraic geometry can be expressed as the solution to an equation involving the determinant of an appropriate matrix.
Room invented Room squares in a brief note published in 1955.

A Room square, named after Thomas Gerald Room, is an n × n array filled with n + 1 different symbols in such a way that:

Each cell of the array is either empty or contains an unordered pair from the set of symbols
Each symbol occurs exactly once in each row and column of the array
Every unordered pair of symbols occurs in exactly one cell of the array.
An example, a Room square of order seven, if the set of symbols is integers from 0 to 7:
(It is known that a Room square (or squares) exist if and only if n is odd but not 3 or 5.)



DEATHS

1683 John Collins (5 March 1624 in Wood Eaton (4km north of Oxford), England - 10 Nov 1683 in London, England) was an accountant and publisher who corresponded extensively with the mathematicians of his day. Collins's importance is, as Barrow said, being "the English Mersenne" . He corresponded with Barrow, David Gregory, James Gregory, Newton, Wallis, Borelli, Huygens, Leibniz, Tschirnhaus and Sluze.
Collins published books by Barrow and Wallis and left a collection of 2000 books and an uncounted number of manuscripts.
He did publish works of his own, however. For instance he published works on sundials, trigonometry for navigation and the use of the quadrant. He had a paper on cartography published and also wrote on accounting, compound interest and annuities. His major works were An introduction to merchant's accounts (1652), The sector on a quadrant (1658), Geometrical dialling (1659), The mariner's plain scale new plained (1659) and, in 1664, he published Doctrine of Decimal Arithmetick. *SAU




1914 Nils Christofer Dunér (21 May 1839, 10 Nov 1914)Swedish astronomer who studied the rotational period of the Sun when he became director of the Uppsala Observatory (1888). By measuring the Doppler shift of the spectral lines of light from the approaching and receding edges of the sun, he made the significant discovery that the rotational period differs from about 25.5 days near the Sun's equator but up to 38.5 days near the Sun's poles.*TIS




1931 Charlotte Angas Scott (8 June 1858 in Lincoln, England
- 10 Nov 1931 in Cambridge, England) studied at Cambridge but was not allowed to take her degree. After graduate work at Cambridge she became the first Head of Mathematics at Bryn Mawr College in Pennsylvania USA. In 1894 Scott published an important textbook An Introductory Account of Certain Modern Ideas and Methods in Plane Analytical Geometry. In 1899 she became an editor of the American Journal of Mathematics and continued an impressive publication record. She also served on the Council of the American Mathematical Society and served as its vice-president in 1905. *SAU
In 1880, Scott obtained special permission to take the Cambridge Mathematical Tripos Exam, as women were not normally allowed to sit for the exam. She came eighth on the Tripos of all students taking them, but due to her sex, the title of "eighth wrangler," a high honour, went officially to a male student.

At the ceremony, however, :

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.

Because she could not attend the award ceremony, Scott celebrated her accomplishment at Girton College where there were cheers and clapping at dinner, a special evening ceremony where the students sang "See the Conquering Hero Comes", received an ode written by a staff member, and was crowned with laurels.

After this incident women were allowed to formally take the exam and their exam scores listed, although separately from the men's and thus not included in the rankings. *Wik




1950 Jacques Inaudi (October 15, 1867 – November 10, 1950) Born to a poor family in the Italian Piedmont, Jacques Inaudi began life as a shepherd but soon discovered a prodigious talent for calculation, and soon he was giving exhibitions in large cities.
Camille Flammarion wrote, “He was asked, for example, how many minutes have elapsed since the birth of Jesus Christ, or what the population would be if the dead from the past ten centuries were resurrected, or the square root of a number of twelve digits, and he gave the response accurately and in two or three minutes — while amusing himself with another activity.”
“The subtraction of numbers consisting of twenty-four figures is an easy matter for him,” reported Scientific American. “Problems for which logarithm tables are generally used he solves mentally with wonderful precision.”
Unlike other prodigies, Inaudi did not visualize his work. “I hear the figures,” he told Alfred Binet, “and it is my ear which retains them; I hear them resounding after I have repeated them, and this interior sensation remains for a long time.”
Inaudi’s father had approached Flammarion hoping that his son could be educated toward a career in astronomy. “It had been an error, whichever way one looked at it,” Flammarion wrote 10 years later. “In science, one cannot make use of his methods, of his adapted formulae, which are tailored to mental calculation.” It was just as well: “Regarding his financial position, he now has, as a result of the curiosity his ability has aroused, a salary, which is over three times that of the Director of the Paris Observatory.” *Greg Ross, Futlty Closet




1970 Heinz Rutishauser (30 January 1918 in Weinfelden, Switzerland; 10 November 1970 in Zürich) was a Swiss mathematician and a pioneer of modern numerical mathematics and computer science. *Wik
Rutishauser of ETH Zurich is considered the most important Swiss pioneer from the early era of computer science. He went down in history as the founder of “automatic programming” and as one of the authoritative fathers of the Algol programming language.





1986 Leona Woods (August 9, 1919;La Grange, Illinois, – November 10, 1986; Santa Monica, California), later known as Leona Woods Marshall and Leona Woods Marshall Libby, was an American physicist who helped build the first nuclear reactor and the first atomic bomb.
At age 23, she was the youngest and only female member of the team which built and experimented with the world's first nuclear reactor (then called a pile ), Chicago Pile-1, in a project led by her mentor Enrico Fermi. In particular, Woods was instrumental in the construction and then utilization of geiger counters for analysis during experimentation. She was the only woman present when the reactor went critical. She worked with Fermi on the Manhattan Project, and, together with her first husband John Marshall, she subsequently helped solve the problem of xenon poisoning at the Hanford plutonium production site, and supervised the construction and operation of Hanford's plutonium production reactors.
After the war, she became a fellow at Fermi's Institute for Nuclear Studies. She later worked at the Institute for Advanced Studies in Princeton, New Jersey, the Brookhaven National Laboratory, and New York University, where she became a professor in 1962. Her research involved high-energy physics, astrophysics and cosmology. In 1966 she divorced Marshall and married Nobel laureate Willard Libby. She became a professor at the University of Colorado, and a staff member at RAND Corporation. In later life she became interested in ecological and environmental issues, and she devised a method of using the isotope ratios in tree rings to study climate change. She was a strong advocate of food irradiation as a means of killing harmful bacteria.
She died at St. John's Medical Center from an anesthesia-induced stroke.*Wik


1988  Otto Haupt (born 5 March 1887 in Würzburg; died 10 November 1988 in Bad Soden) was a German mathematician.
Haupt obtained his PhD in 1911 under the supervision of Georg Rost and Emil Hilb at the University of Würzburg, and became a professor at the University of Erlangen-Nuremberg. He retired from teaching in 1953, but continued his mathematical research for many subsequent years.
In 1918 he was married to Edith Hughes. Despite her Jewish ancestry, she survived the Nazi period unharmed in Erlangen, and lived to 1981.

Haupt specialized in geometry and real analysis; many of his research publications related to the four-vertex theorem on local minima and maxima of curvature. He also wrote textbooks on algebra and calculus.
In 1987, his centenary year, a birthday conference was given in his honor at the University of Erlangen.
He was awarded honorary doctorates from the University of Bonn, the University of Nantes and the University of Würzburg. *Wik




1994 William Higinbotham (25 Oct 1910, 10 Nov 1994)American physicist who invented the first video game, Tennis for Two, as entertainment for the 1958 visitor day at Brookhaven National Laboratory, where he worked (1947-84) then as head of the Instrumentation Division. It used a small analogue computer with ten direct-connected operational amplifiers and output a side view of the curved flight of the tennis ball on an oscilloscope only five inches in diameter. Each player had a control knob and a button. Late in WW II he became electronics group leader at Los Alamos, New Mexico, where the nuclear bomb was developed. After the war, he became active with other nuclear scientists in establishing the Federation of American Scientists to promote nuclear non-proliferation.*TIS



1998 Jean Leray (7 Nov 1906 in Chantenay, near Nantes, Loire-Inférieure, France
- 10 Nov 1998 in La Baule, Loire-Atlantique, France) was a French mathematician, who worked on both partial differential equations and algebraic topology.
He was born in Chantenay-sur-Loire (today part of Nantes). He studied at École Normale Supérieure from 1926 to 1929. He received his Ph.D. in 1933. In 1934 Leray published an important paper that founded the study of weak solutions of the Navier–Stokes equations  In the same year, he and Juliusz Schauder discovered a topological invariant, now called the Leray–Schauder degree, which they applied to prove the existence of solutions for partial differential equations lacking uniqueness.

From 1938 to 1939 he was professor at the University of Nancy. He did not join the Bourbaki group, although he was close with its founders.

His main work in topology was carried out while he was a prisoner of war in a camp in Edelbach, Austria from 1940 to 1945. He concealed his expertise on differential equations, fearing that its connections with applied mathematics could lead him to be asked to aid the German war effort.

Leray's work of this period proved seminal to the development of spectral sequences and sheaves. These were subsequently developed by many others, each separately becoming an important tool in homological algebra.

He returned to work on partial differential equations from about 1950.

He was professor at the University of Paris from 1945 to 1947, and then at the Collège de France until 1978.

He was awarded the Malaxa Prize (Romania, 1938), the Grand Prix in mathematical sciences (French Academy of Sciences, 1940), the Feltrinelli Prize (Accademia dei Lincei, 1971), the Wolf Prize in Mathematics (Israel, 1979), and the Lomonosov Gold Medal (Moscow, 1988). He was elected to the American Academy of Arts and Sciences and the American Philosophical Society in 1959 and the United States National Academy of Sciences in 1965.




2008 Kiyoshi Itō (September 7, 1915 – 10 November 2008) was a Japanese mathematician whose work is now called Itō calculus. The basic concept of this calculus is the Itō integral, and among the most important results is Itō's lemma. The Itō calculus facilitates mathematical understanding of random events. His theory is widely applied in various fields, and is perhaps best known for its use in financial mathematics.*Wik




2015 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







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