Pat'sBlog

Tuesday, 25 December 2018

On This Day in Math - December 25

God Bless Us, Everyone

Me, and Tiny Tim

The 359th day of the year; 359 is a Sophie Germain prime. If you start with n=89 and iterate 2n+1 you will get a string of primes that includes 359. (How many in all?)

It is also the smallest Sophie Germain prime whose reversal, 953 is also a Sophie Germain prime
and Sadly, the last day of the year that is prime. (On most years this year day occurs on Christmas Day, a fitting day for the last prime day of the year .)

EVENTS
1843 Sir Henry Cole British industrial designer, museum director and writer who produced the first commercial Christmas card. In 1843, wishing to save much handwriting of seasonal correspondence, Cole introduced the world's first commercial Christmas card. He commissioned artist John Callcott Horsley to make the artwork for 1000 hand-coloured lithographs. (Individuals' homemade Christmas cards had existed earlier.) (See Image at top)

1640 Fermat's theorem on sums of two squares states that an odd prime p can be expressed as:

p= x² + y² with x and y integers, if and only if $ p\equiv 1 mod 4 $

The prime numbers for which this is true are called Pythagorean primes. For example, the primes 5, 13, 17, 29, 37 and 41 are all congruent to 1 modulo 4,

Albert Girard was the first to make the observation, describing all positive integral numbers (not necessarily primes) expressible as the sum of two squares of positive integers; this was published in 1625.The statement that every prime p of the form 4n+1 is the sum of two squares is sometimes called Girard's theorem. For his part, Fermat wrote an elaborate version of the statement (in which he also gave the number of possible expressions of the powers of p as a sum of two squares) in a letter to Marin Mersenne dated December 25, 1640: for this reason this version of the theorem is sometimes called Fermat's Christmas theorem. *Wik

1656 Huygens (who was a bachelor) spent Christmas Day making the ﬁrst model of a pendulum clock. *VFR(And then he was visited by three spirits.... oops, wrong story)

In 1741, the Centigrade temperature scale was devised by astronomer Anders Celsius (1701-44) and incorporated into a Delisle thermometer at Uppsala in Sweden. Celsius divided the fixed-point range of the Fahrenheit scale (the freezing and boiling temperatures of water) into 100 equal divisions, but curiously set the freezing point at 100 and the boiling point at 0. This reverse scaling was changed to match the sense of the other temperature scales after Celsius's death.*TIS

1758 Halley’s comet ﬁrst sighted after he predicted its return. After Newton explained planetary motion, he suggested that comets could have elongated elliptical orbits. Halley’s comet has eccentricity 0.9675. [UMAP Journal, 4(1983), p. 162] *VFR
In 1758, the predicted return of Halley's comet was first sighted by German farmer and amateur astronomer, Johann Georg Palitzsch, as a faint object in Pisces. Edmund Halley had predicted in 1705 the return of the comet to the Earth's vicinity every 75.5 years. For the first time the scientific prediction had been proven. Halley himself had died 16 years before this new event. Palitzsch also observed the 6 Jun 1761 transit of Venus, when he saw a black band linking Venus and the Sun near the beginning and end of the transit ("black drop effect") and correctly interpreted this as evidence that Venus possessed an atmosphere. He also measured the period of the variation of the brightness of the star Algol. *TIS
The BAYEUX TAPESTRY (Tapisserie de la Reine Mathilde) includes a clear picture of Halley's Comet, as shown on the stamp below.

and here is a Blog regarding the return in 1758.

In 1780, Luigi Galvani recorded, "The electric fluid should be considered a means to the nervo-muscular force." He reached this conclusion from work in his laboratory in Bologna, Italy, after a series of experiments and his accidental discovery that muscles are operated by electrical stimulation of nerves. He worked diligently along these lines, but waited for eleven years before he published the results and an ingenious and simple theory. His theory was that of a nervous electric fluid, secreted by the brain, conducted by the nerves, and stored in the muscles. Though his ideas were abandoned by scientists on account of later discoveries, his work opened the way to new research in the physiology of muscle and nerve and pioneered the subject of electrophysiology. *TIS

1884 On the first Christmas after it was printed, the future classic, Flatland, was reviewed in the Times UK, which gave it a less than sterling review.

In 1999, space shuttle Discovery's astronauts finished their maintenance work on the Hubble Space Telescope, installing correcting optics to repair problems due to a design flaw in the mirror. The first images the Hubble Telescope took after its original launch were disappointingly fuzzy, but after this repair mission the instrument returned crisp images of a clarity never before possible from terrestrial observatories *TIS

BIRTHS
1642 Isaac Newton born on Julian Calendar. (5 January 1643 New style) *VFR
Born 25 Dec 1642; died 20 Mar 1727. English physicist and mathematician, who made seminal discoveries in several areas of science, and was the leading scientist of his era. His study of optics included using a prism to show white light could be split into a spectrum of colours. The statement of his three laws of motion are fundamental in the study of mechanics. He was the first to describe the moon as falling (in a circle around the earth) under the same influence of gravity as a falling apple, embodied in his law of universal gravitation. As a mathematician, he devised infinitesimal calculus to make the calculations needed in his studies, which he published in Philosophiae Naturalis Principia Mathematica (Mathematical Principles of Natural Philosophy, 1687)*TIS

1763 Claude Chappe (25 Dec 1763; 23 Jan 1805) French engineer who invented the semaphore visual telegraph. He began experimenting in 1790, trying various types of telegraph. An early trial used telescopes, synchronised pendulum clocks and a large white board, painted black on the back, with which he succeeded in sending a message a few sentences long across a 16km (10mi) distance. To simplify construction, yet still easily visible to read from far away, he changed to using his semaphore telegraph in 1793. Smaller indicators were pivoted at each end of large horizontal member. The two indicators could each be rotated to stand in any of eight equally spaced positions. By setting them at different orientations, a set of corresponding codes was used to send a message.*TIS

1900 Antoni Szczepan Zygmund (25 Dec 1900 in Warsaw, Russian Empire (now Poland)
- 30 May 1992 in Chicago, Illinois, USA) Zygmund's work in harmonic analysis has application in the theory of waves and vibrations. He also did major work in Fourier analysis and its application to partial differential equations.*SAU

1905 Gottfried Maria Hugo Köthe (born 25 December 1905 in Graz; died 30 April 1989 in Frankfurt) was an Austrian mathematician working in abstract algebra and functional analysis.*SAU Köthe's best known work has been in the theory of topological vector spaces. In 1960, volume 1 of his seminal monograph Topologische lineare Räume was published (the second edition was translated into English in 1969). It was not until 1979 that volume 2 appeared, this time written in English. He also made contributions to the theory of lattices. *Wik

DEATHS
1921 Piers Bohl (October 23, 1865 – December 25, 1921) was a Latvian mathematician, who worked in differential equations, topology and quasi-periodic functions.
He was born in 1865 in Walk, Livonia, in the family of a poor Baltic German merchant. In 1884, after graduating from a German school in Viljandi, he entered the faculty of physics and mathematics at the University of Tartu. In 1893 Bohl was awarded his Master's degree. This was for an investigation of quasi-periodic functions. The notion of quasi-periodic functions was generalised still further by Harald Bohr when he introduced almost-periodic functions. *Wik

1929 Percy Alexander MacMahon (b. 26 September 1854, Sliema, Malta – 25 December 1929, Bognor Regis, England) was a mathematician, especially noted in connection with the partitions of numbers and enumerative combinatorics. MacMahon was elected a Fellow of the Royal Society in 1890. He received the Royal Society Royal Medal in 1900, the Sylvester Medal in 1919, and the Morgan Medal by the London Mathematical Society in 1923. MacMahon was the President of the London Mathematical Society from 1894 to 1896.
MacMahon is best known for his study of symmetric functions and enumeration of plane partitions; see MacMahon Master theorem. His two volume Combinatory analysis, published in 1915/16, is the first major book in enumerative combinatorics. MacMahon also did pioneering work in recreational mathematics and patented several successful puzzles.*WIK

1930 Eugen Goldstein (5 Sep 1850, 25 Dec 1930) German physicist who discovered and named canal rays (1886) which emerge through holes in the anodes of low-pressure electrical discharge tubes (later shown to be positively charged particles). Earlier, he coined the term "cathode ray" (1876) emitted from a cathode. He was the first to see that they could cast a shadow, and were emitted at right angles to the surface. He also investigated the wavelengths of light emitted by metals and oxides when canal rays impinge on them. When the Berlin Urania, opened in 1889 it had five scientific departments and a "science theatre", it was Goldstein who had recommended the "hall of physics in which the visitor could experiment on his own". Students of his that continued his work included Wien and Stark. *TIS

1941 Theodor Molien or Fedor Eduardovich Molin (September 10, 1861 - December 25, 1941) was a Baltic-German mathematician. He was born in Riga, Latvia, which at that time was a part of Russian Empire. Molien studied associative algebras and polynomial invariants of finite groups.*Wik

1944 Wilhelm Kutta was a German engineer who is best known for his work on the numerical solution of differential equations (the Runge-Kutta method).*SAU Kutta was born in Pitschen, Upper Silesia (today Byczyna, Poland). He attended the University of Breslau from 1885 to 1890, and continued his studies in Munich until 1894, where he became the assistant of Walther Franz Anton von Dyck. From 1898, he spent half a year at the University of Cambridge.[1] From 1899 to 1909 he worked again as an assistant of von Dyck in Munich; from 1909 to 1910 he was adjunct professor at the Friedrich Schiller University Jena. He was professor at the RWTH Aachen from 1910 to 1912. Kutta became professor at the University of Stuttgart in 1912, where he stayed until his retirement in 1935.
In 1901, he co-developed the Runge-Kutta method, used to solve ordinary differential equations numerically. He is also remembered for the Zhukovsky-Kutta aerofoil, the Kutta-Zhukovsky theorem and the Kutta condition in aerodynamics. Kutta died in Fürstenfeldbruck, Germany in 1944. *Wik

2000 Willard Van Orman Quine (June 25, 1908 – December 25, 2000) (known to intimates as "Van")[1] was an American philosopher and logician in the analytic tradition. From 1930 until his death 70 years later, Quine was continuously affiliated with Harvard University in one way or another, first as a student, then as a professor of philosophy and a teacher of mathematics, and finally as a professor emeritus who published or revised several books in retirement. He filled the Edgar Pierce Chair of Philosophy at Harvard from 1956 to 1978. A recent poll conducted among philosophers named Quine one of the five most important philosophers of the past two centuries.[2] He won the first Schock Prize in Logic and Philosophy in 1993, for "his systematical and penetrating discussions of how learning of language and communication are based on socially available evidence and of the consequences of this for theories on knowledge and linguistic meaning.*Wik

2018 Nancy Grace Roman (May 16, 1925..Nashville, Tennessee, U.S.-December 25, 2018 (aged 93)) was an American astronomer and one of the first female executives at NASA. She is known to many as the "Mother of Hubble" for her role in planning the Hubble Space Telescope. Throughout her career, Roman was also an active public speaker and educator, and an advocate for women in the sciences.
When Roman was eleven years old, she showed interest in astronomy by forming an astronomy club among her classmates in Nevada. She and her classmates got together once a week and learned about constellations from books. Although discouraged by those around her, Roman knew by the time she was in high school that she wanted to pursue her passion for astronomy. She attended Western High School in Baltimore where she participated in an accelerated program and was graduated in three years. *Wik

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

Monday, 24 December 2018

On This Day in Math - December 24

The travelers looked up to see an omen shining in the sky,
Earthrise: See 1968 below

The 358th day of the year; 358 is twice a prime, and the sum of six consecutive primes.

The sum of the first 358 prime numbers is itself a prime number.

and in case you were curious, the 358th digit of pi (after the decimal point) is 3.

EVENTS
1754 Euler writes to Muller in St Petersburg and describes d'Alembert as "the most argumentative man in the world," and calls him, "hated by everyone in Paris." *Thomas L. Hankins, Jean d'Alembert: science and the Englightenment; pg 58

1819 Bernard Bolzano was dismissed from his theological chair at the University of Prague and put under police supervision for his unorthodox religious views. In mathematics he helped remove the scandal of inﬁnitesimals from the calculus. *VFR

1849 Guass writes to the Astronomer Johann Franz Encke in response to Encke's remarks about the Frequency of Primes.

"Most Honored Friend!
. . .The kind communication of your remarks on the frequency of prime numbers
was interesting to me in more than one respect. You have reminded me of
my own pursuit of the same subject, whose first beginnings occurred a very long
time ago, in 1792 or 1793, when I had procured for myself Lambert’s supplement
to the table of logarithms. Before I had occupied myself with the finer
investigations of higher arithmetic, one of my first projects was to direct my
attention to the decreasing frequency of prime numbers, to which end I counted
them up in several chiliads (sets of a thousand) and recorded the results on one of the affixed white sheets. I soon recognized, that under all variations of this frequency, on average, it is nearly inversely proportional to the logarithm..."

Guass never published his results. The first published version of the Prime Number Theorem was by Legendre in 1798. *John Derbyshire, Prime Obsession

1899 the Physico-Mathematic Society of Kazan (Russia) celebrated a Jubilee in honor of the twenty-fifth year of professional and scientific service of its President, Professor A. Vasiliev. It is also the fifteenth year of his presidency. Professor Vasiliev has been an extraordinarily important figure in Russian science. Outside of Russia he has chiefly been known for his remarkable discourse on Lobachevski. *The American Mathematical Monthly, Vol. 7, No. 1 (Jan., 1900), p. 30

1906 First Long Range transmisson of voice: Reginald Aubrey Fessenden was a Canadian inventor and engineer with 300 patents. He broadcast the first program of voice and music. In 1893, Fessenden moved to Pittsburgh as the head of electrical engineering at the university, Fessenden read of Marconi's work and began experimenting himself. Marconi could only transmit Morse code. But Fessenden's goal was to transmit the human voice and music. He invented the "continuous wave": sound superimposed onto a radio wave for transmission. A radio receiver extracts the signal so the listener with the original sound. Fessenden made the first long-range transmissions of voice on Christmas Eve 1906 from a station at Brant Rock, Massachusetts, heard hundreds of miles out in the Atlantic.*TIS He used a 42 kHz radio frequency Alexanderson alternator which produced about 1kW of power. Although Fessenden's work made voice radio possible, it would take 10 years and the First World War before it became commonplace. Throughout this period, radio was still seen primarily as point-to-point communication between transmitting stations--a sort of wireless telephone. *CHM

1912 Irving Fisher (1867-1947), a Yale professor, patented an archiving system with index cards. On 1 Jul 1925, Fisher's own firm, the Index Visible Company, merged with its principal competitor to form Kardex Rand Co., later Remington Rand, still later Sperry Rand. Fisher earned about $$1 million$ for the invention, which grew to the princely sum of $$9 million$ before being lost in the stock market crash of 1929. Fisher is widely regarded as the greatest economist America has produced, who made much use of mathematics in his work.*TIS

1968 On Christmas Eve, the Apollo 8 astronauts saw the entirety of Earth for the first time. Turing their cameras to the Earth they took the first three pictures of the whole earth from space. The one above, by William Anders, has been called "the most influential environmental photograph ever taken." *Wik, NASA

In 2004, the Huygens probe began a 22-day descent towards Saturn's largest moon, Titan. It had been launched as part of the Cassini spacecraft in 1997, and together they entered Saturn's orbit in June 2004. As the paths of the spacecraft and Titan converged, Cassini ejected the Huygens probe, sending it on a 22-day coast toward the cloud-covered moon. It landed 14 Jan 2005, and sent back photgraphs of the moon's surface. Cassini will remain in orbit around Saturn until at least July 2008. The Cassini-Huygens mission to study Saturn and its 33 known moons resulted from an unprecedented cooperative effort between the NASA of the United States, the European Space Agency and Italy's space program, at a cost of $3.3 billion. *TIS

BIRTHS
1740 Anders Johan Lexell (December 24, 1740 – December 11, 1784 (Julian calendar: November 30)) was a Swedish-born Russian astronomer, mathematician, and physicist who spent most of his life in Russia where he is known as Andrei Ivanovich Leksel.
Lexell made important discoveries in polygonometry and celestial mechanics; the latter led to a comet named in his honor. La Grande Encyclopédie states that he was the prominent mathematician of his time who contributed to the spherical trigonometry with new and interesting solutions, which he took as a basis for his research of comet and planet motion. His name was given to one of the theorems about spherical triangles.
Lexell was one of the most prolific members of the Russian Academy of Sciences at that time, having published 66 papers in 16 years of his work there. A statement attributed to Leonhard Euler expresses high approval of Lexell's works: "Besides Lexell, such a paper could only be written by D'Alambert or me". Daniel Bernoulli also praised his work, writing in a letter to Johann Euler "I like Lexell's works, they are profound and interesting, and the value of them is increased even more because of his modesty, which adorns great men".
Lexell did not have a family and kept up a close friendship with Leonhard Euler and his family. He witnessed Euler's death at his house and succeeded him to the chair of the mathematics department at the Russian Academy of Sciences, but died the following year. The asteroid 2004 Lexell is named in his honour, as is the lunar crater Lexell.*Wik

1818 James Prescott Joule (24 Dec 1818; 11 Oct 1889) English physicist who established that the various forms of energy - mechanical, electrical, and heat - are basically the same and can be changed, one into another. Thus he formed the basis of the law of conservation of energy, the first law of thermodynamics. He discovered (1840) the relationship between electric current, resistance, and the amount of heat produced. In 1849 he devised the kinetic theory of gases, and a year later announced the mechanical equivalent of heat. Later, with William Thomson (Lord Kelvin), he discovered the Joule-Thomson effect. The SI unit of energy or work , the joule (symbol J), is named after him. It is defined as the work done when a force of 1 newton moves a distance of 1 metre in the direction of the force.*TIS

1822 Charles Hermite (24 Dec 1822; 14 Jan 1901) French mathematician whose work in the theory of functions includes the application of elliptic functions to provide the first solution to the general equation of the fifth degree, the quintic equation. In 1873 he published the first proof that e is a transcendental number. Hermite is known also for a number of mathematical entities that bear his name, Hermite polynomials, Hermite's differential equation, Hermite's formula of interpolation and Hermitian matrices. Poincaré is the best known of Hermite's students.*TIS

1838 Thorvald Nicolai Thiele (24 December 1838 – 26 September 1910) was a Danish astronomer, actuary and mathematician, most notable for his work in statistics, interpolation and the three-body problem. He was the first to propose a mathematical theory of Brownian motion. Thiele introduced the cumulants and (in Danish) the likelihood function; these contributions were not credited to Thiele by Ronald A. Fisher, who nevertheless named Thiele to his (short) list of the greatest statisticians of all time on the strength of Thiele's other contributions.
Thiele also was a founder and Mathematical Director of the Hafnia Insurance Company and led the founding of the Danish Society of Actuaries. It was through his insurance work that he came into contact with fellow mathematician Jørgen Pedersen Gram. Asteroid 843 Nicolaia is named in his honor. *Wik

1868 Emanuel Lasker (24 Dec 1868 in Berlinchen, Prussia (now Barlinek, Poland) - 11 Jan 1941 in New York, USA) Lasker became World Chess Champion in 1894 and held the championship until 1921. In mathematics he introduced the notion of a primary ideal. *SAU

1904 Sir William Hunter McCrea FRS (13 December 1904, Dublin – 25 April 1999) was an English astronomer and mathematician. He went to Trinity College, Cambridge in 1923 where he studied Mathematics, later gaining a PhD in 1929 under Ralph H. Fowler. He was later appointed a lecturer of Mathematics at the University of Edinburgh in 1929. He also served as reader and assistant professor at Imperial College London. In 1936 he became head of the mathematics department at the Queen's University of Belfast. After serving in the war, he joined the mathematics department at Royal Holloway College in 1944 (the McCrea Building on Royal Holloway's campus is named after him). In 1965, McCrea created the astronomy centre of the physics department at the University of Sussex.
In 1928, he studied Albrecht Unsöld's hypothesis, and discovered that three quarters of the Sun is made of Hydrogen, and about one quarter is Helium, with 1% being other elements. Previous to this many people thought the Sun consisted mostly of Iron. After this, people realized most stars consist of Hydrogen.
McCrea was president of the Royal Astronomical Society from 1961-3 and president of Section A of the British Association for the Advancement of Science from 1965-6. He was knighted in 1985. He won the Gold Medal of the Royal Astronomical Society in 1976. McCrea died on April 25, 1999 in Lewes. *Wik

1910 William Hayward Pickering (24 Dec 1910; 15 Mar 2004) Engineer and physicist, head of the team that developed Explorer 1, the first U.S. satellite. He collaborated with Neher and Robert Millikan on cosmic ray experiments in the 1930s, taught electronics in the 1930s, and was at Caltech during the war. He spent the rest of his career with the Jet Propusion Laboratory, becoming its Director (1954) with responsibility for the U.S. unmanned exploration of the planets and the solar system. Among these were the Mariner spacecraft to Venus and Mercury, and the Viking mission to Mars. The Voyager spacecraft yielded stunning photographs of the planets Jupiter and Saturn.*TIS

DEATHS
(How sad to be one of these people who died on Christmas Eve)
1872 William John Macquorn Rankine (5 Jul 1820, 24 Dec 1872) Scottish engineer and physicist and one of the founders of the science of thermodynamics, particularly in reference to steam-engine theory. As the chair (1855) of civil engineering and mechanics at Glasgow, he developed methods to solve the force distribution in frame structures. Rankine also wrote on fatigue in the metal of railway axles, on Earth pressures in soil mechanics and the stability of walls. He was elected a Fellow of the Royal Society in 1853. Among his most important works are Manual of Applied Mechanics (1858), Manual of the Steam Engine and Other Prime Movers (1859) and On the Thermodynamic Theory of Waves of Finite Longitudinal Disturbance. *TIS (Many students are not aware there is a absolute temperature scale called the Rankine, named for him)

1882 Johann Benedict Listing (25 July 1808 in Frankfurt am Main, Germany - 24 Dec 1882 in Göttingen, Germany)wrote one of the earliest texts on Topology. he studied the figure of the earth in minute detail; he made observations in meteorology, terrestrial magnetism, and spectroscopy; he wrote on the quantitative determination of sugar in the urine of diabetics; he promoted the nascent optical industry in Germany and better street lighting in Göttingen; he travelled to the world exhibitions in London 1851, Vienna 1873 and London 1876 as an observer for his government; he assisted in geodetic surveys; ... he invented a good many terms [other than topology], some of which have became current: "entropic phenomenona", "nodal points", "homocentric light", "telescopic system", " geoid" ...he coined "one micron" for the millionth of a metre ...*SAU

1927 William Henry Dines (5 Aug 1855, 24 Dec 1927) was an English meteorologist (like his father) and inventor of related measurement instruments such as the Dines pressure tube anemometer (the first instrument to measure both the velocity and direction of wind, 1901), a very lightweight meteorograph, and a radiometer (1920). He joined the Royal Meteorological Society study of the cause of the disastrous Tay Bridge collapse of 1879. His measurements of upper air conditions, first with kites and later by balloon ascents (1907), brought an understanding of cyclones from dynamic processes in the lower stratosphere rather than thermal effects nearer to the ground.*TIS

1962 Wilhelm Friedrich Ackermann (29 March 1896 – 24 December 1962) was a German mathematician best known for the Ackermann function, an important example in the theory of computation.*Wik

1994 Alfred Leon Foster (13 July 1904 in New York City, New York, USA - 24 Dec 1994 in Berkeley, California, USA) Foster went on to define the concept of a primal algebra generalising a Boolean algebra within the theory of varieties of universal algebras. In 1953 showed that the variety generated by a primal algebra has the same essential structure as the variety of Boolean algebras. He continued devoting his efforts to the structure theory of algebras that are generalizations of Boolean algebras and, more than ten years down the line in 1966, he published Families of algebras with unique (sub-)direct factorization. Equational characterization of factorization in Mathematische Annalen.*SAU

2000 Laurence Chisholm Young (14 July 1905 – 24 December 2000) was a mathematician known for his contributions to measure theory, the calculus of variations, optimal control theory, and potential theory. He is the son of William Henry Young and Grace Chisholm Young, both prominent mathematicians.
The concept of Young measure is named after him. *Wik

Sunday, 23 December 2018

On This Day in Math - December 23

The mathematician may be compared to a designer of garments, who is utterly oblivious of the creatures whom his garments may fit. To be sure, his art originated in the necessity for clothing such creatures, but this was long ago; to this day a shape will occasionally appear which will fit into the garment as if the garment had been made for it. Then there is no end of surprise and delight.
~Tobias Danzig

The 357th day of the year; there are 357 odd numbers in the first 46 rows of Pascal's Arithmetic triangle. (How many evens?)

357 is made up of three consecutive prime digits, and is the product of three distinct primes, 3 x 7 x 17=357

There are 21 year dates for which the sum of the divisors is a square number. 357 is the 20th of them. 1+3+7+17+21+51+119+357=576=24²

EVENTS

1493 The German version of the Nuremberg Chronicle - in German 'Schedelsche Weltchronik' - was published. It is one of the best-documented early printed books - an incunabulum - and one of the first to successfully integrate illustrations and text. Moreover, it was the most extensively illustrated book of the 15th century. See more detail and some of the beautiful graphics at *Yovisto

In 1672, astronomer Giovanni Cassini discovered Saturn's moon Rhea, the fifth major satellite of Saturn, which may be one of the most heavily cratered satellites in the solar system. Its surface appears to be saturated with craters, but long, bright linear features can be seen on the trailing hemisphere and linear ridges can be seen in the leading hemisphere. These ancient features may record changes in Rhea's shape due to internal heating or cooling. Rhea is 950 miles (1500 km) in diameter. Its largest crater is 190 miles (300 km) in diameter. Cassini also discovered three more of Saturn's major moons -- Iapetus, Tethys, and Dione. In 1675, he discovered that Saturn's rings are split largely into two parts by a narrow gap - known since as the "Cassini Division." *TS

1690 Flamsteed observes Uranus, but doesn’t recognize it as undiscovered planet. *VFR

1750, Benjamin Franklin was severely shocked while electrocuting a turkey.*TIS (although I heard he described the meat as unusually tender)

1751 Jacobi called this the birthday of elliptic functions because on this day a work by the Italian mathematician Giulio Carlo Fagnano, which had been sent to the Berlin Academy, was handed to Euler for review. The study of this work led Euler to his important investigations on elliptic integrals and to the discovery of the addition theorem. [Cajori, Historical Introduction to Mathematical Literature, p. 213) *VFR Fagnano had discovered a way to find the length of a lemniscate.

1763 Price read Bayes’s essay to the Royal Society. *VFR Bayes never published what would eventually become his most famous accomplishment; his notes were edited and published after his death by Richard Price. In his later years he took a deep interest in probability. Stephen Stigler feels that he became interested in the subject while reviewing a work written in 1755 by Thomas Simpson,but George Alfred Barnard thinks he learned mathematics and probability from a book by de Moivre *Wik

1788 First use of "catenary", rather than the longer, more formal Latin "catenaria", may have been in a letter from Thomas Jefferson to Thomas Paine. Paine had written to Jefferson regarding the design of Iron Bridges. Jefferson's response was:

You hesitate between the catenary, and portion of a circle. I have lately received from Italy a treatise on the equilibrium of arches by the Abbe Mascheroni. It appears to be a very scientifical work. I have not yet had time to engage in it, but I find that the conclusions of his demonstrations are that 'every part of the Catenary is in perfect equilibrium.'

The earliest citation for catenary in the OED2 is from the above letter. *Jeff Miller

1907 William Thompson, Lord Kelvin; died of a severe chill on 17 December 1907.
The Royal Society asked the Dean of Westminster if Kelvin could be buried in the Abbey and he agreed. The funeral was on 23 December and he lies to the south of Sir Isaac Newton's grave in the nave. On the previous night the coffin, covered by a purple pall, had rested in St Faith's chapel. The simple stone reads: WILLIAM THOMSON LORD KELVIN 1824-1907.
In 1913 a stained glass window, designed by J.Ninian Comper, was erected near the grave. This contains large figures of King Henry V and Abbot William Colchester and below is an inscription "In memory of Baron Kelvin of Largs. Engineer, Natural Philosopher. B.1824.D.1907". His coat of arms and those of Glasgow University are shown. The window was the gift of engineers from Great Britain and America. *Wik

1947 Bardeen and Brattain demonstrate the transistor to the Bell Labs brass
It was the point-contact transistor, made from strips of gold foil on a plastic triangle, pushed down into contact with a slab of germanium. To measure the amplification they hooked up a microphone to one end of the device and a loudspeaker to the other. One by one, the men picked up the microphone and whispered hello; the loudspeaker at the other end of the circuit shouted HELLO!
Later, realizing that another major breakthrough in electronics had occurred in Bell’s lab, Shockley wrote Hearing speech amplified by the transistor was in tradition of Alexander Graham Bell’s famous ‘Mr. Watson, come here, I want you.’*CHM (The name transistor came from its electrical property known as trans-resistance.) The next day Brattain noted the important event into his notebook.

1949 J. R. Arnold and W. F. Libby publish "Age determinations by radiocarbon content: checks with samples of known age", the results of their experiments on using Carbon 14 for dating ancient organic materials in Science Magazine. The experiments were done on samples of wood of known age. For example, two samples taken from the tombs of two Egyptian kings, Zoser and Sneferu, independently dated to 2625 BC plus or minus 75 years, were dated by radiocarbon measurement to an average of 2800 BC plus or minus 250 years. *Wik

In 1953, Dr. Robert Oppenheimer was notified that his security clearance had been suspended. (He had directed the Manhattan Project that produced the atomic bombs used during WW II). There were allegations questioning his trustworthiness for association with Communists. By telegram dated 29 Jan 1954, he requested a hearing. On 4 Mar 1954, he submitted his answer to the original notification. Within two weeks, the Commission informed him who would conduct the hearing, to be led by Gordon Gray. The hearing before the Gray Board began 12 Apr 1954. It returned a result on 29 Jun 1954 that by a vote of 4 to1, it had made a decision against reinstating Dr. J. Robert Oppenheimer's access to classified information.*TIS

1955 The term ALPHAMETIC was coined in 1955 by J. A. H. Hunter (Schwartzman). In the Dec. 23, 1955, Toronto Globe & Mail Hunter wrote, "These alphametics seem set to take the place of crosswords as a new craze... Don't forget that each letter stands for a particular figure" *Earliest Known Uses of Some of the Words of Mathematics
An alphametic is a peculiar type of mathematical puzzle, in which a set of words is written down in the form of an ordinary "long-hand" addition sum, and it is required that the letters of the alphabet be replaced with decimal digits so that the result is a valid arithmetic sum. For an example one can do no better than the first modern alphametic, published by the great puzzlist H.E. Dudeney in the July 1924 issue of Strand Magazine:

SEND
MORE
-----
MONEY

whose (unique) solution is:

9567
1085
-----
10652
*Alphametic Page BTW alph + a = metic is a self referential name since it is, itself, and alphametic.

In 1968, American astronauts on Apollo 8 became the first men to orbit the Moon. The three-man crew was Frank Borman (Commander), James A. Lovell, Jr. (Command Module Pilot) and William Anders (Lunar Module Pilot). Not only was this the first manned flight to and from the Moon, but Apollo 8 served to validate many of the technical procedures necessary to support upcoming lunar missions. During ten lunar orbits, the astronauts took star sightings to pinpoint landmarks, surveyed landing sites, took both still and motion pictures and made two television transmissions to Earth. It was also the world's first manned flight to escape the influence of Earth's gravity. Launched on 21 Dec 1968, the mission lasted 6 days 3 hours until recovery on 27 Dec 1968. *TIS

Apollo 8 crew. From left: Borman, Anders, Lovell. NASA.

1987 Egypt issued a stamp honoring the mathematician Ali Mustafa Mousharafa (1898–1950). [Scott #1147]. *VFR Dr. Ali Moustafa Mosharafa Pasha was an Egyptian theoretical physicist. He was professor of applied mathematics in the Faculty of Science at Cairo University, and also served as its first dean. *Wik

BIRTHS
1872 Georgii Pfeiffer did important work on partial differential equations.*SAU

1909 John Hamilton Curtiss is born on December 23, 1909. He obtained an MS degree in statistics from Northwestern University in 1930, and a PhD from Harvard in 1935. He obtained an MS degree in statistics from Northwestern University in 1930, and a PhD from Harvard in 1935. He had taught at Cornell University (1935-1943) and had served in U.S. Navy (1943-1946). In 1946 Curtiss joined National Bureau of Standards, where in 1947 he became a chief of the Applied Mathematical Division (AMD), the first centralized national computing center dedicated to accelerate the progress of USA in the computing industry. AMD's expertise proved the necessity of development of the UNIVAC, the SEAC, and the SWAC computers. At the same time Curtiss played the crucial role in the organization of ACM, then Eastern Association of Computing Machinery, and in 1947 he became the first ACM president.
Curtiss remained at NBS until 1953. From 1954 to 1959 he was an executive director of the American Mathematical Society. In 1959 he became a professor of mathematics at the University of Miami, where he remained until his death in 1977. While no one can recall Curtiss at the console of a computer, he always said that "I was involved in the salt mines of computing." *CHM

1936 Peter L. Hammer (December 23, 1936 - December 27, 2006) was an American mathematician native to Romania. He contributed to the fields of operations research and applied discrete mathematics through the study of pseudo-Boolean functions and their connections to graph theory and data mining.*Wk

1938 Robert E(lliot) Kahn (23 Dec 1938, ) American computer scientist who co-created the packet-switching protocols that enable computers to exchange information on the Internet. In the late 1960s Kahn realized that a packet-switching network could effectively transmit large amounts of data between computers. Along with fellow computer scientists Vinton Cerf, Lawrence Roberts, Paul Baran, and Leonard Kleinrock, Kahn built the ARPANET, the first network to successfully link computers around the country. Kahn and Cerf also developed the Transmission Control Protocol (TCP) and the Internet Protocol (IP), which together enable communication between different types of computers and networks; TCP/IP is the standard still in use today. *TIS

1943 Mikhail Leonidovich Gromov (23 December 1943 - ), is a French–Russian mathematician known for important contributions in many different areas of mathematics. He is considered a geometer in a very broad sense of the word. In 2009 he was awarded the Abel Prize "for his revolutionary contributions to geometry." *Wik

DEATHS
1722 Pierre Varignon (Caen 1654 – December 23, 1722 Paris) was a French mathematician. He was educated at the Jesuit College and the University in Caen, where he received his M.A. in 1682. He took Holy Orders the following year.
Varignon gained his first exposure to mathematics by reading Euclid and then Descartes' La Géométrie. He became professor of mathematics at the Collège Mazarin in Paris in 1688 and was elected to the Académie Royale des Sciences in the same year. In 1704 he held the departmental chair at Collège Mazarin and also became professor of mathematics at the Collège Royal. He was elected to the Berlin Academy in 1713 and to the Royal Society in 1718. Many of his works were published in Paris in 1725, three years after his death. His lectures at Mazarin were published in Elemens de mathematique in 1731.
Varignon was a friend of Newton, Leibniz, and the Bernoulli family. Varignon's principal contributions were to graphic statics and mechanics. Except for l'Hôpital, Varignon was the earliest and strongest French advocate of infinitesimal calculus, and exposed the errors in Michel Rolle's critique thereof. He recognized the importance of a test for the convergence of series, but analytical difficulties prevented his success. Nevertheless, he simplified the proofs of many propositions in mechanics, adapted Leibniz's calculus to the inertial mechanics of Newton's Principia, and treated mechanics in terms of the composition of forces in Projet d'une nouvelle mécanique in 1687. Among Varignon's other works was a 1699 publication concerning the application of differential calculus to fluid flow and to water clocks. In 1690 he created a mechanical explanation of gravitation. In 1702 he applied calculus to spring-driven clocks. *Wik
(Varignon's theorem is a statement in Euclidean geometry by Pierre Varignon that was first published in 1731. It deals with the construction of a particular parallelogram from an arbitrary quadrangle.

The midpoints of the sides of an arbitrary quadrangle form a parallelogram. If the quadrangle is convex or reentrant, i.e. not a crossing quadrangle, then the area of the parallelogram is half as big as the area of the quadrangle.

If one introduces the concept of oriented areas for n-gons, then the area equality above holds for crossed quadrangles as well.
The Varignon parallelogram exists even for a skew quadrilateral, and is planar whether or not the quadrilateral is planar. *Wik )

1834 Thomas Robert Malthus (13 Feb 1766; 23 Dec 1834 at age 68) English economist and demographer who can be regarded as a pioneer sociologist. He was one of the first to systematically analyze human society when he published his theories in An Essay on the Principle of Population. Malthus predicted population would always outrun the food supply and that would result in famine, disease or war to reduce the number of people. As Malthus observed the Industrial Revolution was causing a rapid increase in population, he indicated keeping improved social conditions would require imposing strict limits on reproduction. Reading the book inspired Charles Darwin to reflect upon the survival of the fittest individuals in the process of natural selection in evolving populations of any organism. Alfred Russell Wallace likewise acknowledged his theory was stimulated by the book by Malthus. *TIS

1890 Edward Sang,(30 Jan 1805 in Kirkcaldy, Fife, Scotland - 23 Dec 1890) A native of Fife, Sang wrote extensively on mathematical, mechanical, optical and actuarial topics. *SAU

1907 Pierre (-Jules-César) Janssen (22 Feb 1824, 23 Dec 1907) was a French astronomer who in 1868 devised a method for observing solar prominences without an eclipse (an idea reached independently by Englishman Joseph Norman Lockyer). Janssen observed the total Sun eclipse in India (1868). Using a spectroscope, he proved that the solar prominences are gaseous, and identified the chromosphere as a gaseous envelope of the Sun. He noted an unknown yellow spectral line in the Sun in 1868, and told Lockyer (who subsequently recognized it as a new element he named helium, from Greek "helios" for sun). Janssen was the first to note the granular appearance of the Sun, regularly photographed it, and published a substantial solar atlas with 6000 photographs (1904). *TIS

1973 Gerard Peter Kuiper (7 Dec 1905, 23 Dec 1973) Dutch-born American astronomer, who discovered Miranda, a moon of Uranus, and Nereid, a moon of Neptune. The Kuiper Belt is so-named after his original suggestion of its existence outside the orbit of Neptune before it was confirmed as a belt of small bodies. He measured the diameter of Pluto. In the Martian atmosphere Kuiper detected carbon dioxide, but the absence of oxygen (1947). In the 1960s, Kuiper pioneered airborne infrared observing using a Convair 990 aircraft and served as chief scientist for the Ranger spacecraft crash-landing probes of the moon. By analyzing Ranger photographs, he identified landing sites on the lunar surface most suitable for safe manned landings. *TIS

1989 Richard Rado FRS(28 April 1906 – 23 December 1989) was a Jewish German mathematician. He earned two Ph.D.s: in 1933 from the University of Berlin, and in 1935 from the University of Cambridge. He was interviewed in Berlin by Lord Cherwell for a scholarship given by the chemist Sir Robert Mond which provided financial support to study at Cambridge. After he was awarded the scholarship, Rado and his wife left for the UK in 1933. He made contributions in combinatorics and graph theory. He wrote 18 papers with Paul Erdős. In 1964, he discovered the Rado graph (The Rado graph contains all finite and countably infinite graphs as induced subgraphs..)
In 1972, he was awarded the Senior Berwick Prize*Wik

1992 Robert Eugene Marshak (October 11, 1916 – December 23, 1992) was an American physicist dedicated to learning, research, and education.
Marshak was born in the Bronx, New York City. His parents were immigrants to New York from Minsk. He was educated at Columbia University.
Marshak received his PhD from Cornell University in 1939. Along with his thesis advisor, Hans Bethe, he discovered many of the fusion aspects involved in star formation. This helped him on his work for the Manhattan Project, in Los Alamos, during World War II.
In 1947, at the Shelter Island Conference, Marshak presented his two-meson hypothesis about the pi-meson, which were discovered shortly thereafter.[1]
In 1957, he and George Sudarshan proposed a V-A ("vector" minus "axial vector") Lagrangian for weak interactions, which was later independently discovered by Richard Feynman and Murray Gell-Mann. His biography below, is explicit about it "Perhaps Marshak's most significant scientific contribution was the proposal of the V-A Theory of Weak Interactions (the fourth force in nature) in collaboration with his student George Sudarshan. Unfortunately, the pair published the theory only in a conference proceedings for a meeting in Italy. Six months later, a different derivation of the same concept was published by Feynman and Gell-Mann in a mainstream scientific journal. Marshak had talked with Feynman about the general problem in California some time before. Though the V-A Concept was considered to be one of the most important contributions to theoretical physics, a Nobel Prize was never awarded for it." Sudarshan himself later commented in a TV interview in 2006 that Murray Gell-Mann got the idea from him, in an informal coffee time!
He was Chairman of the Department of Physics at the University of Rochester for fourteen years (1956 to 1970)
He was the President of the City College of New York from 1970-1979.
Marshak died by accidental drowning in Cancún, Mexico in 1992. *Wik

2001 Donald Clayton Spencer (April 25, 1912 – December 23, 2001) was an American mathematician, known for major work on deformation theory of structures arising in differential geometry, and on several complex variables from the point of view of partial differential equations. He was born in Boulder, Colorado, and educated at the University of Colorado and MIT.
He wrote a Ph.D. in diophantine approximation under J. E. Littlewood at the University of Cambridge, completed in 1939. He had positions at MIT and Stanford before his appointment in 1950 at Princeton University. There he was involved in a major series of collaborative works with Kunihiko Kodaira on the deformation of complex structures, which had a profound influence on the theory of complex manifolds and algebraic geometry, and the conception of moduli spaces.
He later worked on pseudogroups and their deformation theory, based on a fresh approach to overdetermined systems of PDEs (bypassing the Cartan-Kähler ideas based on differential forms by making an intensive use of jets). Formulated at the level of various chain complexes, this gives rise to what is now called Spencer cohomology, a subtle and difficult theory both of formal and of analytical structure. This is a kind of Koszul complex theory, taken up by numerous mathematicians during the 1960s. In particular a theory for Lie equations formulated by Malgrange emerged, giving a very broad formulation of the notion of integrability.
After his death, a mountain peak outside of Silverton, Colorado was named in his honor. *Wik

Saturday, 22 December 2018

On This Day in Math - December 22

*Wik

Scientists are the true driving force of civilization.
~James Burke

The 356th day of the year; There are 356 ways to partition the number 36 into distinct parts without a unit.

356 is the last day of the year that will be a self-number, (there is no number n such that n+ digit sum of n = 356)

356 = 2² x 89. Numbers that are the product of a prime and the square of a prime are sometimes called Einstein numbers, after E = m c²

EVENTS
968 First clear description of the corona seen during a total eclipse, by a chronicler in Constantinople. The first mention of the corona may have been due to Plutarch, who lived from about AD 46 to 120. Plutarch's book 'On the Face in the Orb of the Moon' contains a reference to 'a certain splendour' round the eclipsed Sun which could well have been the corona. *Patrick Poitevin ‏@PatrickPoitevin

1666 Seven mathematicians and seven physicists met at the king’s Library to inaugurate the French Academy of sciences. They would not receive a formal decree of protection from Louis XIV until 1699. For three centuries women were not allowed as members of the Academy. The first female full member was Yvonne Choquet-Bruhat in 1979. *VFR The society was an outgrowth of an informal community of scientists who coordinated their research efforts through the efforts of Marin Mersenne, a monk at the Minim monastery, who had exchanged 10,000 letters with them. *TIS

1669 John Wallis in a letter to Thomas Smith of Madalene College writes “In a dark night, in bed, without pen, ink or paper or anything equivalent, I did by memory extract the square root of 30000,00000,00000,00000,00000,00000,00000,00000, which I found to be 1,73205,08075,68077,29353, etc. and did the next day commit it to writing.” (Wallis wrote this some 12 years after the event, but there is sufficient evidence elsewhere of his prodigious powers of calculation to lend the story some credence.) *Jacqueline A. Stedall, Our Own Nation

1680 The Great Comet of 1680, sometimes called Kirch's Comet was the first comet discovered by telescope, but it was visible to the naked eye for several months, some say even in the daylight. The image at right is a drawing of comet as it appeared on December 22, 1680 over Beverwijk, attributed to Rochus van Even *@rijksmuseum.

1831 The first use of Sir Francis Beaufort's scale of wind force in an official log was by Captain Robert Fitzroy on the first day of the voyage of exploration of the HMS Beagle that included a young naturalist named Charles Darwin. *Isaac's Storm, Erik Larson

1859 On a warm Saturday in late March of 1859, a small country doctor just 70 miles west of Paris

Dr. Lescarbault's Observatory *Wik

retreated to his barn observatory to check on a hunch about the inconsistencies of the orbit of Mercury, and on that eventful day, the dedicated amateur found a small planet, or asteroid which he carefully measured to be inside the orbit of Mercury. After careful measurements, and rechecking, he closed his books and ...... did nothing. For months, he continued to observe to see if he could improve, or repeat, his observations, but only seventy miles from the center of the Astronomical Universe, Where Le Verrier, the man who had discovered Neptune with his pen, held audience.
It was not until Dec 22, that he put pen to paper to inform the astronomical world of his discovery. He decided to write after he read a journal article in "Cosmos" by the great man himself, that Dr. Lescarbault felt bold enough to entrust a local Inspector of Roads and Bridges with a letter to the Great Le Verrier informing him of his discovery. After a brief interrogation in the rural home and examination of his work, Le Verrier pronounced the work good, and within a week took the humble Doctor's observations and produced an orbit for the new planet, another example of Le Verrier's magic of producing celestial objects from his mathematical pen. Within a few months, in early 1860, the press had a name for his new creation, Vulcan explained the mystery of Mercury's Perihelion Precession in seeming defiance of Newton's laws. *Thomas Levenson, The Hunt for Vulcan

1866 L E Becker wrote to Darwin to ask if he would “be so very good as to send us a paper to be read at our first meeting”. “Of course we are not so unreasonable as to desire that you should write anything specially for us” Becker said, “but I think it possible you may have by you a copy of some paper such as that on the Linum which you have communicated to the learned societies but which is unknown and inaccessible to us unless through your kindness.”
Darwin responded by sending not one but three papers to be read at the ladies’ inaugural meeting. Whether Darwin realized that he was providing materials for a feminist organization is unclear, although Becker’s use of headed paper and the enclosure in her letter to Darwin of the society’s first pamphlet certainly made no secret of her political affiliations.
Regardless, what is interesting is that despite what he said in the public context about women’s intellectual in-capabilities and designated social role, in private his thoughts and actions were very different. Darwin was happy to work in collaboration with many women like Becker. He encouraged women’s scientific interests wherever possible, frequently sharing observations, samples and reading materials with women across the world. In some rare instances he was even happy to acknowledge that a woman’s scientific skill and knowledge might be superior to his own! *Darwin and Gender, the blog)

In 1870, Charles Augustus Young, an American astronomer, made the first observations of the flash spectrum of the Sun. He was a pioneer in the study of the spectrum of the sun and experimented in photographing solar prominences in full sunlight. On 22 Dec 1870, at the eclipse in Spain, he saw the lines of the solar spectrum all become bright for perhaps a second and a half (the "flash spectrum") and announced the "reversing layer." In his career, he also proved the gaseous nature of the sun's corona. By exploring from the high altitude of Sherman, Wy. (1872), he more than doubled the number of bright lines he had observed in the chromosphere. By a comparison of observations, he concluded that magnetic conditions on the earth respond to solar disturbances.

1877 Alfred Beach, editor of Scientific American wrote, "Mr. Thomas A. Edison recently came into this office, placed a little machine on our desk, turned a crank, and the machine inquired as to our health, asked how we liked the phonograph, informed us that it was well, and bid us a cordial good night. These remarks were not only perfectly audible to ourselves, but to a dozen or more persons gathered around." *TIS

1882 First electrical lights for a Christmas tree. Edward Hibberd Johnson, an American electrical engineer and inventor,spent many years in various business projects with Thomas Edison. Johnson created the first electric lights on a Christmas tree on 22 Dec 1882.*TIS

In 1885, a U.S. patent for a gravity switchback railway was issued to La Marcus Adna Thompson of Coney Island, N.Y. (No. 332,762). In 1884, Thompson, the "Father of the Gravity Ride," opened a 600-ft roller-coaster at Coney Island at 6-mph maximum. Its popularity enabled him to recoup his $1,600 investment in only three weeks. In this patent he described a railway on trestles with two parallel tracks undulating vertically. At the end of the first track, a switch automatically allowed the car to return on the second track. His design in an earlier patent (20 Jan 1885, No. 310,966) needed passengers to temporarily get out of the car at the end of the first track while assistants prepared it to return on the second track.) *TIS

1955 The FINAC, the Italian Mark I*, is inaugurated in Rome. The Mark I*, the commercial prototype of Manchester's Mark I, was built by English Ferranti Ltd., for UNESCO's International Computational Center in Rome. This completely electronic computer arrived. *CHM

2006 The journal Science honored Grigori Perelman Perelman's proof of the Poincaré conjecture as the scientific "Breakthrough of the Year", the first time this had been bestowed in the area of mathematics. *Wik

2010 India issued a stamp featuring Srinivasa Ramanujan, who was born on this day, to celebrate their National Mathematics Day.

BIRTHS
1765 Johann Friedrich Pfaff born in Stuttgart, Germany. Laplace, when asked who the greatest mathematician in Germany, replied, Pfaﬀ. When the questioner said he should have thought Gauss was, Laplace replied: “Pfaff is the greatest mathematician in Germany; but Gauss is the greatest in all Europe.” [Quoted from Cajori, A History of Mathemtics, in AMM 8(1901), p. 26] *VFR (22 Dec 1765; 21 Apr 1825) He proposed the first general method of integrating partial differential equations of the first order. Pfaff did important work on special functions and the theory of series. He developed Taylor's Theorem using the form with remainder as given by Lagrange. In 1810 he contributed to the solution of a problem due to Gauss concerning the ellipse of greatest area which could be drawn inside a given quadrilateral. His most important work on Pfaffian forms was published in 1815 when he was nearly 50, but its importance was not recognised until 1827 when Jacobi published a paper on Pfaff's method. *TIS

1799 Nicholas Joseph Callan (22 Dec 1799; 10 Jan 1864) Irish pioneering scientist in electrical science, who invented the induction coil (1836) before that of better-known Heinrich Ruhmkorff. Callan's coil was built using a horseshoe shaped iron bar wound with a secondary coil of thin insulated wire under a separate winding of thick insulated wire as the "primary" coil. Each time a battery's current through the "primary" coil was interrupted, a high voltage current was produced in the electrically separate "secondary" coil. By 1837, Callan used a clock mechanism to rock a wire in and out of a small cup of mercury to interrupt the circuit 20 times/sec on a giant induction machine, producing 15-inch sparks (estimated at 600,000 volts)*TIS

1819 Pierre-Ossian Bonnet whose favorite ﬁeld was differential geometry, a ﬁeld opened by Euler, Monge, and Gauss, but lacking systematic treatment when Bonnet took it up in the 1840s. *VFR

1824 Francesco Brioschi (22 Dec 1824 in Milan, Lombardo-Veneto (now Italy)- 14 Dec 1897 in Milan, Italy) a professor at Pavia who contributed to the study of mathematical physics.*SAU

1859 Otto Ludwig Hölder (22 Dec 1859 in Stuttgart, Germany - 29 Aug 1937 in Leipzig, Germany) worked on the convergence of Fourier series and in 1884 he discovered the inequality now named after him. He became interested in group theory through Kronecker and Klein and proved the uniqueness of the factor groups in a composition series.*SAU

1859 Enrico Barone (22 Dec 1859; 14 May 1924) Italian mathematical economist who built on the general equilibrium theory of Léon Walras and was instrumental in convincing Walras to incorporate variable production techniques - and, by extension, marginal productivity theory - into the Walras theory. Barone's greatest contribution was in getting the "Socialist Calculation" debate started with his famous 1908 article. His position was that it was indeed possible in a collectivist state for a planning agency to calculate prices for maximum efficiency. He was the first to apply indifference curve analysis to compare the relative burdens of income taxes and excise taxes (1912). He opposed "progressive" taxation schemes as based on dubious utilitarian calculations.*TIS

1887 Srinivasa Ramanujan (22 Dec 1887; 26 Apr 1920) Indian mathematician known for his work on hypergeometric series and continued fractions. In number theory, he discovered properties of the partition function. Although self-taught, he was one of India's greatest mathematical geniuses. He worked on elliptic functions, continued fractions, and infinite series. His remarkable familiarity with numbers, was shown by the following incident. While Ramanujan was in hospital in England, his Cambridge professor, G. H. Hardy, visited and remarked that he had taken taxi number 1729, a singularly unexceptional number. Ramanujan immediately responded that this number was actually quite remarkable: it is the smallest integer that can be represented in two ways by the sum of two cubes: 1729=13+123=93+103. *TIS Ramanujan's recognition of 1729 could be partly due to his studying examples of numbers such that $ a^3 + b^3 = c^3 + 1$His papers had several examples of them.

1897 Vojtěch Jarník ( 22 Dec 1897 in Prague, Bohemia (now Czech Republic) - 22 Sept 1970 in Prague, Czechoslovakia) was a Czech mathematician.
His main area of work was in number theory and mathematical analysis; he proved a number of results on lattice point problems. He also developed the graph theory algorithm known as Prim's algorithm.
The Vojtěch Jarník International Mathematical Competition, held each year in Ostrava, is named in his honor.*Wik

1898 Vladimir Aleksandrovich Fock (December 22, 1898 – December 27, 1974) was a Soviet physicist, who did foundational work on quantum mechanics and quantum electrodynamics.*Wik

1911 Grote Reber (22 Dec 1911; 20 Dec 2002) U.S. amateur astronomer and radio engineer who self-financed and built the first radio telescope. He pioneered the new field of radio astronomy, and was the first to systematically study the sky by observing non-visible radiation. After reading about Jansky's discovery (1932) of natural radio emissions from space, Reber constructed a 9-meter dish antenna in his back yard and built three different detectors before finding 160 MHz signals (1939). In 1940 and 1944 he published articles titled Cosmic Static in the Astrophysical Journal. He was the first to express received radio signals in terms of flux density and brightness, first to find evidence that galactic radiation is non-thermal, and first to produce radio maps of the sky (1941).*TIS

1936 James Burke (22 December 1936, ) is a British broadcaster, science historian, author and television producer known amongst other things for his documentary television series Connections (1978) and its more philosophical oriented companion production, The Day the Universe Changed (1985), focusing on the history of science and technology leavened with a sense of humour. The Washington Post has called him "one of the most intriguing minds in the Western world".*Wik

1937 Arthur Jaffe (December 22, 1937, ) is an American mathematical physicist and a professor at Harvard University. He attended Princeton University as an undergraduate obtaining a degree in chemistry, and later Clare College, Cambridge, as a Marshall Scholar, obtaining a degree in mathematics. He then returned to Princeton, obtaining a doctorate in physics.
With James Glimm, he founded the subject called constructive quantum field theory. One of their major achievements was to show the mathematical compatibility of quantum theory, special relativity, and interaction. They did this by proving the existence of the first examples of non-linear, relativistic quantum fields with non-trivial scattering. Jaffe's work in several related fields of mathematics and physics is well-known, including contributions to gauge theory and to non-commutative geometry.
For several years Jaffe was president of the International Association of Mathematical Physics, and later of the American Mathematical Society. He chaired the Council of Scientific Society Presidents.
Jaffe conceived the idea of the Clay Mathematics Institute and its programs, including the employment of research fellows and the Millennium Prizes in mathematics. The latter immediately captured public imagination worldwide. He served as a founding Member, a founding member of the Board, and the founding President of that organization.
Currently Jaffe teaches Mathematical Physics and pursues research at Harvard University. His doctoral students include Joel Feldman, Ezra Getzler, and Clifford Taubes. *Wik

DEATHS
1640 Jean Beaugrand (about 1590 in Paris, France - 22 Dec 1640 in Paris, France) was a French mathematician who published works on Geostatics as well as mathematics. *SAU

1660 André Tacquet (23 June 1612 Antwerp – 22 December 1660 Antwerp, also referred to by his Latinized name Andrea Tacquet[) was a Flemish mathematician and Jesuit Priest. His work prepared ground for the eventual discovery of the calculus.
He was born in Antwerp, and entered the Jesuit Order in 1629. From 1631 to 1635, he studied mathematics, physics and logic at Leuven. Two of his teachers were Saint-Vincent and Francois d'Aguilon.
Tacquet became a brilliant mathematician of international fame and his works were often reprinted and translated (into Italian and English). He helped articulate some of the preliminary concepts necessary for Isaac Newton and Gottfried Leibniz to recognize the inverse nature of the quadrature and the tangent. He was one of the precursors of the infinitesimal calculus, developed by John Wallis. His most famous work, which influenced the thinking of Blaise Pascal and his contemporaries, is Cylindricorum et annularium (1651). In this book Tacquet presented how a moving point could generate a curve and the theories of area and volume. *Wik

1693 Elisabetha Koopman (17 Jan 1647 in Danzig, now Gdańsk, Poland - 22 Dec 1693 in Danzig, now Gdańsk, Poland) was the wife of the Polish astronomer Johannes Hevelius and helped him with his observations.*SAU

1828 William Hyde Wollaston (6 Aug 1766, 22 Dec 1828) English scientist who discovered palladium (1803) and rhodium (1804), during his investigation of platinum ore. He developed a method of forming platinum - powder-metallurgy - and was the first to produce malleable and ductile platinum on a commercial scale. He made his method public at the Royal Society on 28 Nov 1828, shortly before his death. In 1801 he proved experimentally that frictional and current electricity are the same. He is particularly noted for being the first to observe dark lines in the spectrum of the sun which eventually led to the discovery of the elements in the Sun. He constructed the Wollaston prism, a polarizing beam splitter (now applied in the CD player), and invented the camera lucida. *TIS

1867 Jean-Victor Poncelet (1 Jul 1788, 22 Dec 1867). French mathematician and engineer whose study of the pole and polar lines associated with conic led to the principle of duality. While serving as an engineer in Napoleon's 1812 Russian campaign, he was left for dead at Krasnoy, but then captured. During his imprisonment he studied projective geometry and wrote a treatise on analytic geometry. Released in 1814, he returned to France, and in 1822 published Traité des propriétés projectives des figures in which he presented his fundamental ideas of projective geometry such as the cross-ratio, perspective, involution and the circular points at infinity. As a professor of mechanics (1825-35), he applied mechanics to improve waterwheels and was able to double their efficiency. *TIS

1928 Henry Burchard Fine born in Chambersburg, Pennsylvania. After earning his Ph.D. in Germany he joined the Princeton faculty. He is responsible for building that department into a world class mathematics department. The mathematics building at Princeton is named in his honor.*VFR (Fine Hall is the tallest building on the campus) He was president of the American Mathematical Society in 1911-12.Fine wrote:

Euclid's Elements (1891)
The Number System of Algebra (1891; second edition, 1903) PDF/DjVu copy from Internet Archive.
A College Algebra (1904)
Coördinate Geometry, with Henry Dallas Thompson (1909) PDF Copy from University of Michigan Historical Math Collection.
Calculus (1927)
*Wik

1955 Jules-Émile Verschaffelt (27 January 1870, Ghent – 22 December 1955) was a Belgian physicist. He worked at Kamerlingh Onnes’s laboratory in Leiden from 1894 to 1906 and once again from 1914 to 1923. From 1906 to 1914 he worked at the Vrije Universiteit Brussel and from 1923 to 1940 at the Ghent University. *Wik

1994 John Arthur Todd FRS (23 August 1908 – 22 December 1994) was a British geometer. He was born in Liverpool, and went to Trinity College of the University of Cambridge in 1925. He did research under H.F. Baker, and in 1931 took a position at the University of Manchester. He became a lecturer at Cambridge in 1937. He remained at Cambridge for the rest of his working life.[2]
The Todd class in the theory of the higher-dimensional Riemann–Roch theorem is an example of a characteristic class (or, more accurately, a reciprocal of one) that was discovered by Todd in work published in 1937. It used the methods of the Italian school of algebraic geometry. The Todd–Coxeter process for coset enumeration is a major method of computational algebra, and dates from a collaboration with H.S.M. Coxeter in 1936. In 1953 he and Coxeter discovered the Coxeter–Todd lattice. In 1954 he and G. C. Shephard classified the finite complex reflection groups.
In March 1948 he was elected a Fellow of the Royal Society. *Wik

2001 Luís Antoni Santaló Sors (October 9, 1911 – November 22, 2001) was a Spanish mathematician.
He graduated from the University of Madrid and he studied at the University of Hamburg, where he received his Ph.D. in 1936. His advisor was Wilhelm Blaschke. Because of the Spanish Civil War, he moved to Argentina where he became a very famous mathematician.
He studied integral geometry and many other topics of mathematics and science.
He worked as a teacher in the National University of the Littoral, National University of La Plata and University of Buenos Aires. *Wik