***** WARNING!!!!!********** Repeat of some very old jokes
Darryl Brock, A fellow teacher at school sent out some puns today... and I rewrote some of them as .... dare I call them... equations...
***** WARNING!!!!!********** Repeat of some very old jokes
Darryl Brock, A fellow teacher at school sent out some puns today... and I rewrote some of them as .... dare I call them... equations...
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| Scottish Café (Polish: Kawiarnia Szkocka) in Lwów |
Once a sage asked why scholars always flock to the doors of the rich, whilst the rich are not inclined to call at the doors of scholars. "The scholars" he answered, "are well aware of the use of money, but the rich are ignorant of the nobility of science".
al-Biruni
The 347th day of the year; 347 is a safe prime, one more than twice a Sophie Germain Prime, 173. There is only one more safe prime this year.
And from Derek at @MathYearRound, "Adding 2 to any digit of 347 keeps it prime (547, 367 and 349 are prime)."
Derek's comment also points out that 347 is the smaller of a pair of twin primes. I just found out that, "(p, p+2) are twin primes if and only if p + 2 can be represented as the sum of two primes. Brun (1919)" (Brun showed that even if there are an infinity of prime pairs, the sum of their reciprocals converges.)
There are 347 even digits before the 347th odd digit of π. (How often is it true that after 2n digits of π there are n even and n odd digits?)
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| Not the Actual Aurora from 1128 ;-} |
1128 “In the third year of Lothar, emperor of the Romans, in the twenty-eighth year of King Henry of the English…on Saturday, 8 December, there appeared from the morning right up to the evening two black spheres against the sun.” This description of sunspots, and the earliest known drawing of sunspots, appears in John of Worcester’s Chronicle recorded in 1128. On the night of 13 December 1128, astronomers in Songdo, Korea, witnessed a red vapour that “soared and filled the sky” from the northwest to the southwest. A delay of five days is the average delay between the occurrence of a large sunspot group near the center of the Sun – exactly as witnessed by John of Worcester – and the appearance of the aurora borealis in the night sky at relatively low latitudes *Joe Hanson, itsokaytobesmart.com
1743, On Dec 13, Jean-Philippe Loys de Cheseaux spotted a comet in the sky. He was not the first to see the comet, having been preceded by a Dutch astronomer and a German. But the comet has been known ever since as Cheseaux's comet, because de Cheseaux observed it closely for the next three months, and when the comet passed near the sun (passed through perihelion) on Mar. 1, 1744 and soon thereafter sprouted six tails, he was there to sketch the unprecedented phenomenon. Better yet, within months, he brought to press a sizeable book on comets in general, and on the comet of 1743/44 in particular. The book includes an engraving of the six-tailed comet, as drawn on Mar. 8/9, 1744, as well as several diagrams of the path of the comet through the heavens, and its orbit through the solar system, both before and after it grew the six tails.
The six-tailed comet of 1744, detail of an engraving in Jean-Philippe Loys de Cheseaux, Traité de la comete, 1744 (Linda Hall Library)
1883 Felix Klein notes in his references, "Received call to go to Baltimore. Great desire to go there -- at the least a new start." He had received an offer to replace J. J. Sylvester as the Professor of Mathematics at Johns Hopkins University in the form of a telegram from Danial Colt Gilman, President of the University. Klein's response contains two demands. The first is that he will not take less than the salary of the departing Sylvester, ($1000 a year more than the initial offer) and the second that his need for the economic security of his family should be somehow met (in Germany tenured positions included a pension that passed to the wife after the professor's death). Neither demand was met, and eventually Klein would go to Gottingen to develop his famous math institute. *Constance Reid, The Road Not Taken, Mathematical Intelligencer, 1978
1907 Emmy Noether received her Ph.D. degree, summa cum laude, from the University of Erlangen, for a dissertation on algebraic invariants directed by Paul Gordan. She went on to become the world’s greatest woman mathematician. [DSB 10, 137 and A. Dick, p. xiii] *VFR
Emmy's home in Erlangen
In 1920, first U.S. measurement of the size of a fixed star was made on Betelgeuse, the bright red star in the right shoulder of Orion, which was found to be 260 million miles in diameter - 150 times greater than the Sun. Dr. Francis G. Pease made the measurement on the 100-inch telescope at the Mount Wilson Observatory using a beam interferometer designed by Professor A. A. Michelson. Betelgeuse was selected as the first test object since theoretical calculations had suggested that the star was unusually great in size. The apparent angular size of Betelgeuse was found to average about .044 arcseconds. Direct interferometer measurements can only be used with large stars. The majority of stars rely upon more indirect methods of determining stellar sizes. *TIS
Size comparison between Arcturus, Rigel, S Doradus, Antares, and Betelgeuse
An illustration of Orion (horizontally reversed) in al-Sufi's Book of Fixed Stars. Betelgeuze is annotated as Yad al-Jauzā ("Hand of Orion"), one of the proposed etymological origins of its modern name, and also as Mankib al Jauzā' ("Shoulder of Orion").*Wik
1943 Croatia issued a pair of stamps to honor the Serbo-Croation mathematician and physicist Fr. Rugjer Boscovich (1711–1787). [Scott #59-60].*VFR
1957 Niels Bohr comes to Univ of Oklahoma for lecture on "Atoms and Human Knowledge." Jens Rud Nielsen, who joined the OU Physics Department in 1924, was an undergraduate student of Bohr in Denmark. Bohr, one of the founders of quantum mechanics, made two trips to the University of Oklahoma, first in 1937 and again in 1957. *U of Ok digital collection
1991 Stanford Linear Accelerator Center launches first Web site outside Europe
On December 13, 1991 the Stanford Linear Accelerator Center (SLAC) put up the first Web site outside Europe. It let physicists browse the full text of pre-publication scientific papers on SLAC's SPIRES database directly over the Web. This was a radical improvement over the old system, which involved submitting requests and waiting for fax or email versions to be sent back. As a vital service for the international physics community, the SLAC site became an important early step in helping the World Wide Web live up to its ambitious name *CHM
2024. The annual Geminids meteor shower, which streaks across the night sky every year in mid-December, will peak on Monday night and into Tuesday.. The best time to watch is after midnight through dawn on December 14.
The meteors will appear to radiate from a point near the star Castor, in the constellation Gemini.
Under a dark sky with no moon, you might catch 120 Geminid meteors per hour.
1724 Franz Maria Ulrich Theodor Hoch Aepinus (13 Dec 1724; 10 Aug 1802.)
Dutch physicist whose Tentamen theoriae electricitatis et magnetismi (1759; "An Attempt at a Theory of Electricity and Magnetism") was the first work to apply mathematics to the theory of electricity and magnetism. Aepinus' experiments led to the design of the parallel-plate capacitor, a device used to store energy in an electric field. He also discovered the electric properties of the mineral tourmaline and investigated pyroelectricity, the state of electrical polarization produced in tourmaline and various other crystals by a change of temperature. Other achievements of Aepinus include improvements to the microscope, and his demonstration of the effects of parallax in the transit of a planet across the Sun's disk (1764). *TIS
1753 William Nicholson (13 December 1753 – 21 May 1815) was a renowned English chemist and writer on "natural philosophy" and chemistry, as well as a translator, journalist, publisher, scientist, inventor, patent agent and civil engineer.
He is best known for discovering the electrolysis of water, a fundamental process in chemistry. He also published the first monthly scientific journal in Britain, the Journal of Natural Philosophy, Chemistry, and the Arts, which he edited from 1797 to 1814.
In 1797 he began to publish and contribute to the Journal of Natural Philosophy, Chemistry and the Arts, generally known as Nicholson's Journal, the earliest monthly scientific work of its kind in Great Britain— the publication continued until 1814. The journal included the first comprehensive descriptions of aerodynamics with George Cayley's "On Aerial Navigation", which inspired the Wright brothers a hundred years later. In May 1800 he with Anthony Carlisle discovered electrolysis, the decomposition of water into hydrogen and oxygen by voltaic current. The two were then appointed to a chemical investigation committee of the new Royal Institution. But his own interests shortly turned elsewhere.
Besides considerable contributions to the Philosophical Transactions, Nicholson wrote translations of Fourcroy's Chemistry (1787) and Chaptal's Chemistry (1788), First Principles of Chemistry (1788) and a Chemical Dictionary (1795); he also edited the British Encyclopaedia, or Dictionary of Arts and Sciences (6 vols., London, 1809).
Nicholson died in Bloomsbury at the age of 61 on 21 May 1815. *Wik
1759 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
1805 Johann von Lamont (13 Dec 1805; 6 Aug 1879) Scottish-born German astronomer noted for discovering (1852) that the magnetic field of the Earth fluctuates with a 10.3-year activity cycle, but does not correlate it with the period of the sunspot cycle. From 1 Aug 1840, Johann von Lamont (as director of the Royal Astronomical Observatory in Munich) started regular and permanent observations of the earth's magnetic field. In the 1850's he started making regional magnetic surveys in the kingdom of Bavaria, later extended to other states in south Germany, France, Holland, Belgium, Spain, Portugal, Prussia and Denmark. His central European maps with isolines of geomagnetic elements, reduced to 1854, were the first worldwide. *TIS
1867 Kristian Olaf Bernhard Birkeland (born 13 December 1867 in Christiania (today's Oslo) – 15 June 1917 in Tokyo, Japan) was a Norwegian scientist, professor of physics at the Royal Fredriks University in Oslo. He is best remembered for his theories of atmospheric electric currents that elucidated the nature of the aurora borealis. In order to fund his research on the aurorae, he invented the electromagnetic cannon and the Birkeland–Eyde process of fixing nitrogen from the air. Birkeland was nominated for the Nobel Prize seven times.
Birkeland organized several expeditions to Norway's high-latitude regions where he established a network of observatories under the auroral regions to collect magnetic field data. The results of the Norwegian Polar Expedition conducted from 1899 to 1900 contained the first determination of the global pattern of electric currents in the polar region from ground magnetic field measurements.
Birkeland proposed in 1908 in his book The Norwegian Aurora Polaris Expedition 1902–1903 that polar electric currents, today referred to as auroral electrojets, were connected to a system of currents that flowed along geomagnetic field lines into and away from the polar region. Such field-aligned currents are known today as Birkeland currents in his honour. He provided a diagram of field-aligned currents in the book. The book on the 1902–1903 expedition contains chapters on magnetic storms on the Earth and their relationship to the Sun, the origin of the Sun itself, Halley's comet, and the rings of Saturn.
Birkeland's vision of what are now known as Birkeland currents became the source of a controversy that continued for over half a century, because their existence could not be confirmed from ground-based measurements alone. His theory was disputed and ridiculed at the time as a fringe theory by mainstream scientists, most notoriously by the eminent British geophysicist and mathematician Sydney Chapman who argued the mainstream view that currents could not cross the vacuum of space and therefore the currents had to be generated by the Earth. Birkeland's theory of the aurora continued to be dismissed by mainstream astrophysicists after his death in 1917.
Proof of Birkeland's theory of the aurora only came in 1967 after a probe was sent into space. The crucial results were obtained from U.S. Navy satellite 1963-38C, launched in 1963 and carrying a magnetometer above the ionosphere. Magnetic disturbances were observed on nearly every pass over the high-latitude regions of the Earth. These were originally interpreted as hydromagnetic waves, but on later analysis it was realized that they were due to field-aligned or Birkeland currents.
Norwegian 200-kroner banknote,
1887 George Pólya (13 Dec 1887 in Budapest, Hungary - 7 Sept 1985 in Palo Alto, California, USA) Pólya was arguably the most influential mathematician of the 20th century. His basic research contributions span complex analysis, mathematical physics, probability theory, geometry, and combinatorics. He was a teacher par excellence who maintained a strong interest in pedagogical matters throughout his long career. Before going to the United States Pólya had a draft of a book How to solve it written in German. He had to try four publishers before finding one to publish the English version in the United States but it sold over one million copies over the years and has been translated in 17 languages. Schoenfeld described its importance, "For mathematics education and the world of problem solving it marked a line of demarcation between two eras, problem solving before and after Pólya."
Pólya explained in How to solve it that to solve problems required the study of heuristic"The aim of heuristic is to study the methods and rules of discovery and invention .... Heuristic, as an adjective, means 'serving to discover'. ... its purpose is to discover the solution of the present problem. ... What is good education? Systematically giving opportunity to the student to discover things by himself."
He also gave the wise advice, "If you can't solve a problem, then there is an easier problem you can't solve: find it."
Pólya published further books on the art of solving mathematical problems. For example Mathematics and plausible reasoning (1954), and Mathematical discovery which was published in two volumes (1962, 1965).*SAU (The student or teacher who has not read any of these books should go immediately and read them.)
(Every student who dreams of doing advanced math should read "How to Solve it." Every teacher at any level of mathematics should read it multiple times.)
1908 Leon Bankoff (December 13, 1908, New York City, NY -February 16, 1997, Los Angeles, CA), was an American dentist and mathematician.
After a visit to the City College of New York, Bankoff studied dentistry at New York University. Later, he moved to Los Angeles, California, where he taught at the University of Southern California; while there, he completed his studies. He practiced over 60 years as a dentist in Beverly Hills. Many of his patients were celebrities.
Along with Bankoff's interest in dentistry were the piano and the guitar. He was fluent in Esperanto, created artistic sculptures, and was interested in the progressive development of computer technology. Above all, he was a specialist in the mathematical world and highly respected as an expert in the field of flat geometry. Since the 1940s, he lectured and published many articles as a co-author. Bankoff collaborated with Paul Erdős in a mathematics paper and therefore has an Erdős number 1.
From 1968 to 1981, Bankoff was the editor of the Problem Department of Pi Mu Epsilon Journals, where he was responsible for the publication of some 300 top problems in the area of plane geometry, particularly Morley's trisector theorem, and the arbelos of Archimedes. Among his discoveries with the arbelos was the Bankoff circle, which is equal in area to Archimedes' twin circles. Martin Gardner called Bankoff, “one of the most remarkable mathematicians I have been privileged to know.” *Wik
The Bankoff Circle
1910 Charles Alfred Coulson FRS (13 December 1910, Dudley, England – 7 January 1974, Oxford, England) was a British applied mathematician, theoretical chemist and religious author.
His major scientific work was as a pioneer of the application of the quantum theory of valency to problems of molecular structure, dynamics and reactivity. He shared his deep religious belief, as a Methodist lay preacher, with the general public in radio broadcasts, served on the World Council of Churches from 1962 to 1968 and was Chairman of Oxfam from 1965 to 1971.
Coulson was a Senior Lecturer in the Mathematics Department of University College, Dundee, which was administratively part of the University of St. Andrews from 1938 to 1945. He held a Fellowship at the University of Oxford from 1945 to 1947, when he took up the newly appointed Chair of Theoretical Physics at King's College London. He returned to Oxford in 1952 as Rouse Ball Professor of Mathematics and Fellow of Wadham College. He set up and directed the Mathematical Institute. In 1972 he was appointed to the newly created Chair of Theoretical Chemistry, which has since been named for him.
He was elected a Fellow of the Royal Society of Edinburgh in 1941 and a Fellow of the Royal Society of London in 1950. He was awarded the Davy Medal of the Royal Society in 1970, the Faraday and Tilden Medals of the Chemical Society in 1968 and 1969 respectively, and received a dozen honorary degrees from English and other universities. He was a member of the International Academy of Quantum Molecular Science.
In each of his successive appointments, Coulson attracted an active and enthusiastic group of graduate students, short and long term visitors, many of whom held senior university and industrial positions in England and other countries. Many of his students went on to make major contributions in several fields of endeavour.
Coulson was an excellent cricketer and chess player, a warm family man and had a strong sense of humour. He and Eileen were gracious hosts to his students and his associates. The conference in his honour at Brasenose College in 1967 had an impressive international attendance, despite the difficulty of organizing it during a postal strike. *Wik
1921 David Gale (December 13, 1921 – March 7, 2008) was a distinguished American mathematician and economist. He was a Professor Emeritus at University of California, Berkeley, affiliated with departments of Mathematics, Economics, and Industrial Engineering and Operations Research. He has contributed to the fields of mathematical economics, game theory, and convex analysis.*Wik
1923 Philip Warren Anderson (13 Dec 1923, ) is an American physicist who (with John H. Van Vleck and Sir Nevill F. Mott) received the 1977 Nobel Prize for Physics for his research on semiconductors, superconductivity, and magnetism. He made contributions to the study of solid-state physics, and research on molecular interactions has been facilitated by his work on the spectroscopy of gases. He conceived a model (known as the Anderson model) to describe what happens when an impurity atom is present in a metal. He also investigated magnetism and superconductivity, and his work is of fundamental importance for modern solid-state electronics, making possible the development of inexpensive electronic switching and memory devices in computers. *TIS
1048 Abu Arrayhan Muhammad ibn Ahmad al-Biruni (15 Sept 973 in Kath, Khwarazm (now Kara-Kalpakskaya, Uzbekistan) - 13 Dec 1048 in Ghazna (now Ghazni, Afganistan)) one of the major figures of Islamic mathematics ((Al-Biruni was a Persian. His name (Birun) is a Persian word that means "abroad" and refers his birth place HT Mohammad Javidnia). He contributed to astronomy, mathematics, physics, medicine and history. the mathematical contributions of al-Biruni. These include: theoretical and practical arithmetic, summation of series, combinatorial analysis, the rule of three, irrational numbers, ratio theory, algebraic definitions, method of solving algebraic equations, geometry, Archimedes' theorems, trisection of the angle and other problems which cannot be solved with ruler and compass alone, conic sections, stereometry, stereographic projection, trigonometry, the sine theorem in the plane, and solving spherical triangles.
Important contributions to geodesy and geography were also made by al-Biruni. He introduced techniques to measure the earth and distances on it using triangulation. He found the radius of the earth to be 6339.6 km, a value not obtained in the West until the 16th century (see [50]). His Masudic canon contains a table giving the coordinates of six hundred places, almost all of which he had direct knowledge. Not all, however, were measured by al-Biruni himself, some being taken from a similar table given by al-Khwarizmi. The author of [27] remarks that al-Biruni seemed to realize that for places given by both al-Khwarizmi and Ptolemy, the value obtained by al-Khwarizmi is the more accurate.
Al-Biruni also wrote a treatise on time-keeping, wrote several treatises on the astrolabe and describes a mechanical calendar. He makes interesting observations on the velocity of light, stating that its velocity is immense compared with that of sound. He also describes the Milky Way as, "... a collection of countless fragments of the nature of nebulous stars. "
Topics in physics that were studied by al-Biruni included hydrostatics and made very accurate measurements of specific weights. He described the ratios between the densities of gold, mercury, lead, silver, bronze, copper, brass, iron, and tin. Al-Biruni displayed the results as combinations of integers and numbers of the form 1/n, n = 2, 3, 4, ... , 10. *SAU
An imaginary rendition of Al Biruni on a 1973 Soviet postage stamp
1557 Niccolò Fontana Tartaglia (1499, 13 Dec 1557) Italian mathematician who originated the science of ballistics. His proper name was Niccolo Fontana although he is always known by his nickname, Tartaglia, which means the "stammerer." When the French sacked Brescia in 1512, soldiers killed his father and left young Tartaglia for dead with a sabre wound that cut his jaw and palate. In 1535, by winning a competition to solve cubic equations, he gained fame as the discoverer of the formula for their algebraic solution (which was published in Cardan's Ars Magna, 1545) Tartaglia wrote Nova Scientia (1537) on the application of mathematics to artillery fire. He described new ballistic methods and instruments, including the first firing tables. He was the first Italian translator and publisher of Euclid's Elements (1543).*TIS
1565 Conrad Gessner (Konrad Gessner, Conrad Geßner, Conrad von Gesner, Conradus Gesnerus, Conrad Gesner; 26 March 1516 – 13 December 1565) was a Swiss naturalist and bibliographer. His five-volume Historiae animalium (1551–1558) is considered the beginning of modern zoology, and the flowering plant genus Gesneria (Gesneriaceae) is named after him. He is denoted by the author abbreviation Gesner when citing a botanical name. Gessner in 1551 was the first to describe adipose tissue; and in 1565 the first to document the pencil. *Wik See more at The Renaissance Mathematicus blog.
1603 Seigneur (lord) De La Bigotiere François Viète (1540, 13 Dec 1603) French mathematician who introduced the first systematic algebraic notation and contributed to the theory of equations. As Henry IV's cryptographer, he broke an elaborate cipher used by Spanish agents. In algebra, he made a number of innovations in the use of symbolism and several technical terms still in use (e.g., coefficient) were introduced by him. By using algebraic rather than geometric methods, Viète was able to solve a number of geometrical problems. In his In artem analyticam isagoge (1591) Viète introduced such basic algebraic conventions as using letters to represent both known and unknown quantities, while improving the notation for the expression of square and cubic numbers. *TIS
1870 William Chauvenet (24 May 1820, Milford, Pennsylvania - 13 December 1870, St. Paul, Minnesota) was an early American educator. A professor of mathematics, astronomy, navigation, and surveying, he was always known and well liked among students and faculty. In 1841 he was appointed a professor of mathematics in the United States Navy, and for a while served on Mississippi. A year later, he was appointed to the chair of mathematics at the naval asylum in Philadelphia, Pennsylvania. He was instrumental in the founding of the United States Naval Academy at Annapolis, Maryland. In 1859, he was offered a professorship at his alma mater at the same time he was offered a position at Washington University in St. Louis as professor of mathematics and astronomy. He chose St. Louis over New Haven and brought with him a deep love of music and a familiarity with the classics, in addition to being an outstanding figure in the world of science, noted by many historians as one of the foremost mathematical minds in the U.S. prior to the Civil War. It was Chauvenet who mathematically confirmed James B. Eads' plans for the first bridge to span the Mississippi River at St. Louis. The directors of the University chose him to be chancellor when his friend and Yale classmate Joseph Hoyt died in 1862. He came to his chancellorship in the midst of the Civil War in a state divided by the question of slavery.
Washington University went through a great period of growth during his chancellorship, adding dozens of professors, hundreds of students, and several new programs, including the establishment in 1867 of the law school. He served terms as vice president of the United States National Academy of Sciences and president of the American Association for the Advancement of Science, and was a member of both the American Philosophical Society and the American Academy of Arts and Sciences. After his death, the Mathematical Association of America established a prestigious prize in his honor, the Naval Academy named a mathematics building for him, and the U.S. Navy christened two ships Chauvenet.
*Wik
1921 Max Noether (24 Sept 1844 in Mannheim, Baden, Germany - 13 Dec 1921 in Erlangen, Germany) was one of the leaders of nineteenth century algebraic geometry. Although himself a very distinguished mathematician, his daughter Emmy Noether was to bring greater innovation to mathematics than did her father.*SAU
Brill and Max Noether developed alternative proofs using algebraic methods for much of Riemann's work on Riemann surfaces. Brill–Noether theory went further by estimating the dimension of the space of maps of given degree d from an algebraic curve to projective space Pn. In birational geometry, Noether introduced the fundamental technique of blowing up in order to prove resolution of singularities for plane curves.
Noether made major contributions to the theory of algebraic surfaces. Noether's formula is the first case of the Riemann-Roch theorem for surfaces. The Noether inequality is one of the main restrictions on the possible discrete invariants of a surface. The Noether-Lefschetz theorem (proved by Lefschetz) says that the Picard group of a very general surface of degree at least 4 in P3 is generated by the restriction of the line bundle O(1).
Noether and Castelnuovo showed that the Cremona group of birational automorphisms of the complex projective plane is generated by the "quadratic transformation" [x,y,z] ↦ [1/x, 1/y, 1/z]
together with the group PGL(3,C) of automorphisms of P2. Even today, no explicit generators are known for the group of birational automorphisms of P3.
1950 Abraham Wald (October 31, 1902 – December 13, 1950) was a mathematician born in Cluj, in the then Austria–Hungary (present-day Romania) who contributed to decision theory, geometry, and econometrics, and founded the field of statistical sequential analysis. He spent his researching years at Columbia University.Wald applied his statistical skills in World War II to the problem of bomber losses to enemy fire. A study had been made of the damage to returning aircraft and it had been proposed that armor be added to those areas that showed the most damage. Wald's unique insight was that the holes from flak and bullets on the bombers that returned represented the areas where they were able to take damage. The data showed that there were similar patches on each returning B-29 where there was no damage from enemy fire, leading Wald to conclude that these patches were weak spots and that they must be reinforced. *Wik
survivorship bias, notice the cockpit area
2004 David Wheeler, Inventor of the Closed Subroutine, Dies. Wheeler, born February 9, 1927, was Emeritus Professor of Computer Science at Cambridge University and a computer science pioneer. He worked on the original Cambridge EDSAC computer and wrote the first computer program to be stored in a computer’s memory. He pioneered the use of subroutines and data compression. He earned his Ph.D. in 1951 from Cambridge’s Computer Laboratory. (reputed to be the first Ph.D. in computer science) He spent time at the University of Illinois where he made contributions to the architecture of the ILLIAC system there. He later returned to the Cambridge Computer Laboratory and invented the Cambridge Ring and advanced methods of computer testing. He continued to work there until his death, a decade after he had officially retired. *CHM
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
The science of pure mathematics may claim to be the most original creation of the human spirit.
~A N Whitehead
The 346th day of the year; 346 is a Smith number. The sum of its digits equals the sum of the digits of its prime factors. 346 = 2 x 173 and 3+4+6 = 2+1+7+3. One more such number for a day this year. (Smith numbers were named by Albert Wilansky who noticed the property in the phone number (493-7775) of his brother-in-law Harold Smith.) There is only one more year day that is a Smith Number.
346 is also the fourth Franel number, the sum of the cubes of the terms in the nth row of the arithmetic triangle. \( 346 = 1^3 + 4^3 + 6^3 + 4^3 + 1^3\) The numbers are named for Swiss Mathematician Jérôme Franel (1859–1939).
1859 "Karl Weierstrass (1815-1897) used | | in an 1841 essay "Zur Theorie der Potenzreihen," in which the symbol appears on page 67. He also used the symbol in 1859 in "Neuer Beweis des Fundamentalsatzes der Algebra," in which the symbol appears on page 252. This latter essay was submitted to the Berlin Academy of Sciences on December 12, 1859." *Jeff Miller, Earliest Uses of Function Symbols
Cajori says that the first essay was not printed at the time, and Julio González Cabillón believes neither paper was published until 1894, "when the welcome Erster Band [vol. I] of Karl Weierstrass "Mathematische Werke" [Berlin: Mayer & Mueller], saw the light. I do not know to what extent the editors could have interfered with Weierstrass manuscripts. In both papers the notation under discussion does not appear with a definition or with a further comment; thus I am speculating that their subsequent published typesetting might differ from that of Weierstrass original."
The memoir "Zur Theorie der eindeutigen analytischen Functionen," which appeared in Abhandlungen der Koeniglich Akademie der Wissenschaften [pp. 11-60, Berlin 1876, and was reprinted in Zweiter Band (volume II) of Weierstrass "Mathematische Werke" (1895)] has a footnote on page 78 in which Weierstrass remarks:
Ich bezeichne den absoluten Betrag einer complexen Groesse x mit |x|. [I denote the absolute value of complex number x by |x|]
The absolute value of a complex number , a+bi
(also called the modulus ) is defined as the distance between the origin (0,0) and the point (a,b) in the complex plane.
| a+bi |=√(a^2+b^2)
1871, spectroscopic observations of an eclipse in India made by French astronomer Jules Janssen led him to propose that the corona, normally only visible during a solar eclipse, is a physical part of the Sun and is composed of both hot gases and cooler particles.*TIS
His December 19 letter to Lassell describing his observation
1885 In the midst of his inaugural lecture at Oxford, Sylvester “refreshed” the audience with his sonnet “To a missing member of a family group of terms in an algebraical formula.” [Osiris, 1(1936), 109; Nature 33, 7 Jan 1886, p. 228; Collected Mathematical Papers, vol. 4, p. 293] *VFR
In 1901, At Signal Hill, Newfoundland, 1901, in the midst of gale force winds with Ariel equipment in danger, Guglielmo Marconi and his assistant, George Kemp, confirmed the reception of the first transatlantic radio signals. With a telephone receiver and a wire antenna kept aloft by a kite, they heard Morse code for the letter "S" transmitted from Poldhu, Cornwall. Their experiments showed that radio signals extended far beyond the horizon, giving radio a new global dimension for communication in the twentieth century. *ethw.org
1955 English engineer Christopher Cockerell filed the patent for his new invention, the hovercraft, a craft capable of traveling over land, water, mud or ice and other surfaces both at speed and when stationary. *Yovisto
The first mention in the historical record of the concepts behind surface-effect vehicles that used the term hovering was by Swedish scientist Emanuel Swedenborg in 1716. In the 1930-45 period several designs were implemented in different countries but classified. Even Cockerell's model was at first classified, but when declassified, he applied for a patent.
1980 Apple’s initial public offering was the largest IPO since the Ford Motor went public in 1956. Nonetheless, it sold out in minutes. Originally priced to sell at \($14\) a share, the stock opened at \($22\)and all 4.6 million shares were sold almost immediately. The stock rose almost 32% that day to close at \($29\), giving the company a market evaluation of \($1.778 \)billions. The three founders of Apple Computer, Steve Jobs, Steve Wozniak and Mike Markkula weren’t only ones who did well that day. More than 40 of Apple’s 1,000 employees became instant millionaires thanks to the stock options.*CHM

1980, Leonardo daVinci's 36-sheet manuscript Codex Leicester was auctioned at Christie's. It was bought by Armand Hammer for $4.5 million. At the time, it was the highest price paid for a complete manuscript. (It has subsequently been resold). The Codex Leicester, written 1506-10, embraces a wide variety of topics, from astronomy to hydrodynamics, and includes Leonardo's observations and theories related to rivers and seas; the properties of water; rocks and fossils; air; and celestial light. All of this is expressed in his signature mirror writing, as well as in more than 300 pen-and-ink sketches, drawings, and diagrams, many of them illustrating imagined or real experiments.*TIS
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1731 Erasmus Darwin (12 Dec 1731; 18 Apr 1802) Prominent English physician , poet , philosopher, botanist, naturalist and the grandfather of naturalist Charles Darwin and the biologist Francis Galton. Erasmus Darwin was one of the leading intellectuals of 18th century England. As a naturalist, he formulated one of the first formal theories on evolution in Zoonomia, or, The Laws of Organic Life (1794-1796). Although he did not come up with natural selection, he did discuss ideas that his grandson elaborated on sixty years later, such as how life evolved from a single common ancestor, forming "one living filament". Although some of his ideas on how evolution might occur are quite close to those of Lamarck, Erasmus Darwin also talked about how competition and sexual selection could cause changes in species. *TIS
Among many other inventions, all of which he chose not to patent, were a horizontal windmill, which he designed for Josiah Wedgwood (who would be Charles Darwin's other grandfather), a carriage that would not tip over (1766), a steering mechanism for his carriage, known today as the Ackermann linkage, that would be adopted by cars 130 years later (1759), and a method for lifting and lowering barges on canals.
The last he propose two water-filled boxes that would work as counterweights for each other as barges were lifted up or down between levels.
1803 James Challis (12 Dec 1803; 3 Dec 1882) British clergyman and astronomer, famous in the history of astronomy for his failure to discover the planet Neptune. Astronomer and mathematician John Couch Adams had studied the known deviations in the orbit of the planet Uranus which indicated a planet even further out. In 1845, Adams gave Astronomer Royal George Airy a calculated orbital path for the unknown planet. But Airy was more interested in the primary job of navigation and timekeeping observations. Airy informed Challis, who did not begin until July 1846, and actually sighted the new planet four times without recognising it. On 23 Sep 1845, the new planet was instead discovered from Berlin Observatory. Challis admitted that Adam's prediction was within 2° of the planet's position. *TIS
As he reflected in a letter to Airy of 12 October 1846:
I have been greatly mortified to find that my observations would have shewn me the planet in the early part of August if I had only discussed them. ... I delayed doing this ... chiefly because I was making a grand effort to reduce the vast numbers of comet observations which I have accumulated and this occupied the whole of my time.
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1832 Peter Ludwig Mejdell Sylow (12 Dec 1832 in Christiania (now Oslo), Norway - 7 Sept 1918 in Christiania (now Oslo), Norway) In his paper Théorèmes sur les groupes de substitutions which Sylow published in Mathematische Annalen Volume 5 (pages 584 to 594) appear the three Sylow theorems. Cauchy had already proved that a group whose order is divisible by a prime p has an element of order p. Sylow proved what is perhaps the most profound result in the theory of finite groups.
If pn is the largest power of the prime p to divide the order of a group G then:
G has subgroups of order pn,
G has 1 + kp such subgroups,
any two such subgroups are conjugate.
Almost all work on finite groups uses Sylow's theorems.
Sylow became an editor of Acta Mathematica and, in 1894, he was awarded an honorary doctorate from the university of Copenhagen.
Lie had a special chair created for Sylow at Christiania University and Sylow taught at the university from 1898. *SAU
1866 Kazimierz Ajdukiewicz (12 Dec 1890; 12 Apr 1963) Polish logician and semanticist who was the chief contributor to the Warsaw school of philosophy and logic. He is credited with developing in 1920 the first deductive theory for the study of logic based on syntax. The dominant theme of Ajdukiewicz's thought was the problem of the dependence of our knowledge and conception of knowledge on language. His main contributions are in the field of logical syntax (with the theory of semantical categories) and in epistemology, with the so-called "radical conventionalism", a doctrine where he claimed that there exist conceptual apparatuses which are not intertranslatable and that scientific knowledge grows through the replacement of one such conceptual apparatus by another.*TIS
1927 Robert (Norton) Noyce (12 Dec 1927; Jun 1990) was a U.S. engineer and co-inventor (1959), with Jack Kilby, of the integrated circuit, a system of interconnected transistors on a single silicon microchip. He held sixteen patents for semiconductor devices, methods, and structures. In 1968, he and colleague Gordon E. Moore cofounded N.M. Electronics, which later was renamed Intel Corporation. Noyce served as Intel's president and chairman (1968-75), then as vice chairman until 1979. *TIS
1939 Michael Gazzaniga (12 Dec 1939, )American cognitive neuroscientist and author who studies how the brain enables humans to perform those advanced mental functions that are generally associated with what we call the mind. In over four decades of split-brain research he has advanced understanding of how the brain works, by revealing the separate and highly specialized functions and abilities of each hemisphere. Gazzaniga has focused on how the brain facilitates such higher cognitive functions as remembering, speaking, interpreting, and making judgments. His most recent research uses three-dimensional magnetic resonance images of the brain's surface to compare normal brains with, for example, those having a mental disorders such as schizophrenia. *TIS
1685 John Pell (1 March 1611 in Southwick, Sussex, England - 12 Dec 1685 in Westminster, London, England) Malcolm wrote, "The mathematician John Pell is a significant figure in the intellectual history of 17th century England - significant, however, more because of his activities, contacts and correspondence than because of his published work. His few publications are, nevertheless, valuable sources of information about his intellectual biography.
Pell worked on algebra and number theory. He gave a table of factors of all integers up to 100000 in 1668. Pell's equation y2 = ax2 + 1, where a is a non-square integer, was first studied by Brahmagupta and Bhaskara II. Its complete theory was worked out by Lagrange, not Pell. It is often said that Euler mistakenly attributed Brouncker's work on this equation to Pell. However the equation appears in a book by Rahn which was certainly written with Pell's help: some say entirely written by Pell. Perhaps Euler knew what he was doing in naming the equation. *SAU
He introduced the division sign (obelus, ÷) into England. The obelus was first used by Johann Rahn (1622-1676) in 1659 in Teutsche Algebra. Rahn's book was interpreted into English and published, with additions made by John Pell. According to some sources, John Pell was a key influence on Rahn and he may be responsible for the development of the symbol. The word obelus comes from a Greek word meaning a "roasting spit." The symbol wasn't new. It had been used to mark passages in writings that were considered dubious, corrupt or spurious.*TIS
1889 Viktor Bunyakovsky (16 Dec 1804 in Bar, Podolskaya gubernia (now Vinnitsa oblast), Ukraine - 12 Dec 1889 in St Petersburg, Russia) worked on Number Theory as well as geometry, mechanics and hydrostatics. He discovered the Cauchy-Schwarz inequality 25 years before Cauchy or Schwarz.*SAU
1919 Paul Gustav Samuel Stäckel (20 August 1862 — 12 December 1919) was a German mathematician, active in the areas of differential geometry, number theory, and non-Euclidean geometry. In the area of prime number theory, he used the term twin prime for the first time.*Wik
1921 Henrietta Swan Leavitt (4 Jul 1868, 12 Dec 1921) American astronomer known for her discovery of the relationship between period and luminosity in Cepheid variables, pulsating stars that vary regularly in brightness in periods ranging from a few days to several months. Leavitt's greatest discovery came from her study of 1777 variable stars in the Magellanic Clouds. She determined the periods of 25 Cepheid variables and in 1912 announced what has since become known as the famous Period-Luminosity relation: "since the variables are probably nearly the same distance from the earth, their periods are apparently associated with their actual emission of light, as determined by their mass, density, and surface brightness." Today the Period-Luminosity relation is used to calculate the distances of galaxies. *TIS
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1965 Tibor Radó (June 2, 1895 – December 12, 1965) was a Hungarian mathematician who moved to the USA after World War I. He was born in Budapest and between 1913 and 1915 attended the Polytechnic Institute. In World War I, he became a First Lieutenant in the Hungarian Army and was captured on the Russian Front. He escaped from a Siberian prisoner camp and, traveling thousands of miles across Arctic wasteland, managed to return to Hungary.
He received a doctorate from the University of Szeged in 1923. He taught briefly at the university and then became a research fellow in Germany for the Rockefeller Foundation. In 1929, he moved to the United States and lectured at Harvard University and the Rice Institute before obtaining a faculty position in the Department of Mathematics at Ohio State University in 1930. In 1935 he was granted American citizenship.
In the 1920s, he proved that surfaces have an essentially unique triangulation.
In 1933, Radó published "On the Problem of Plateau" in which he gave a solution to Plateau's problem, and in 1935, "Subharmonic Functions".
In World War II he was science consultant to the United States government, interrupting his academic career.
He became Chairman of the Department of Mathematics at Ohio State University in 1948.
His work focused on computer science in the last decade of his life and in May 1962 he published one of his most famous results in the Bell System Technical Journal: the Busy Beaver function and its non-computability ("On Non-Computable Functions").
In computability theory, a busy beaver (from the colloquial expression for an "industrious person") is a Turing machine that attains the maximum "operational busyness" (such as measured by the number of steps performed, or the number of nonblank symbols finally on the tape) among all the Turing machines in a certain class. The Turing machines in this class must meet certain design specifications and are required to eventually halt after being started with a blank tape. *Wik (another source gives his death as Dec 29th of the same year??)
1977 Arthur Erdélyi (2 Oct 1908 in Budapest, Hungary - 12 Dec 1977 in Edinburgh, Scotland) studied in Brno and Prague and came to Scotland before the Second World War to avoid the Nazi invasion of Czechoslovakia. He became a lecturer at Edinburgh and after a period in the USA he returned to Edinburgh as a Professor. He was an expert on Special Functions. He became President of the EMS in 1971. *SAU
1994 Nicolaas Hendrik "Nico" Kuiper (Dutch pronunciation: [kœypəʁ]; 28 June 1920, Rotterdam - 12 December 1994, Utrecht) was a Dutch mathematician, known for Kuiper's test and proving Kuiper's theorem. He also contributed to the Nash embedding theorem.
Kuiper completed his Ph.D. in differential geometry from the University of Leiden in 1946 under the supervision of Willem van der Woude.
He served as director of the Institut des Hautes Études Scientifiques from 1971 to 1985. *Wik
2014 Ivor Owen Grattan-Guinness (23 June 1941 – 12 December 2014) was a historian of mathematics and logic. Grattan-Guinness was born in Bakewell, England; his father was a mathematics teacher and educational administrator. He gained his bachelor degree as a Mathematics Scholar at Wadham College, Oxford, and an MSc (Econ) in Mathematical Logic and the Philosophy of Science at the London School of Economics in 1966. He gained both the doctorate (PhD) in 1969, and higher doctorate (D.Sc.) in 1978, in the History of Science at the University of London. He was Emeritus Professor of the History of Mathematics and Logic at Middlesex University, and a Visiting Research Associate at the London School of Economics.
He was awarded the Kenneth O. May Medal for services to the History of Mathematics by the International Commission for the History of Mathematics (ICHM) on 31 July 2009, at Budapest, on the occasion of the 23rd International Congress for the History of Science. In 2010, he was elected an Honorary Member of the Bertrand Russell Society.
He spent much of his career at Middlesex University. He was a fellow at the Institute for Advanced Study in Princeton, New Jersey, and is a member of the Académie Internationale d'Histoire des Sciences. *Wik
2020 Jack Steinberger (born Hans Jakob Steinberger; May 25, 1921 – December 12, 2020) was a German-born American physicist noted for his work with neutrinos, the subatomic particles considered to be elementary constituents of matter. He was a recipient of the 1988 Nobel Prize in Physics, along with Leon M. Lederman and Melvin Schwartz, for the discovery of the muon neutrino. Through his career as an experimental particle physicist, he held positions at the University of California, Berkeley, Columbia University (1950–68), and the CERN (1968–86). He was also a recipient of the United States National Medal of Science in 1988, and the Matteucci Medal from the Italian Academy of Sciences in 1990.
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