## Thursday 18 July 2024

### On This Day in Math - July 18

Math is the only place where truth and beauty mean the same thing.

-Danica McKellar

(I can't believe I'm doing math quotes by "Winnie" from Wonder Years)

The 199th day of the year; 199 is prime (in fact, all three permutations of the number are prime) and is the sum of three consecutive primes: 61 + 67 + 71, and of five consecutive primes: 31 + 37 + 41 + 43 + 47. (Suddenly struck me I don't know what is the smallest prime that is the sum of consecutive primes in more than one way!)(So the answer was right in front of my face, one of the primes listed above)

199 is the smallest number with an additive persistence of 3. (iterate the sum of the digits. The number of additions required to obtain a single digit from a number n is called the additive persistence of n, and the digit obtained is called the digital root of n. ) 1+9+9 =19, 1+9=10, 1+0 = 1. so the additive persistence is 3 and the digital root is 1.

I like "almost constants". For the 199th day,$( \frac{\sqrt{5} +1}{2})^{11}= 199.0050249987406414902082…$

199 is the last year day that is part of a prime quadruplet, (191, 193, 197, 199)

199 is the smallest number that has an additive persistence of 3, 1+9+9 = 19; 1+9 =10; 1+0=3 *Prime Curios

199 = 100^2-99^2

199 as a palindrome of its own digits, 99+1+99=199= 9*9+9*1+9+1+9+1*9+9*9

199 is a permutable prime, and 919 and 991 are both prime

199 is the first prime number in a sequence of 10 consecutive prime numbers with common difference 210 (tao and green 2008; see R.Taschner "Die Farben der Quadratzahlen" p. 147)the ten primes are 199, 409, 619, 829, 1039, 1249, 1459, 1669, 1879, and 2089.

The next prime after 199 is 211. If they are concatenated in either order, they form a prime, 199211 and 211199 are both prime. *Prime Curios

199 is the smallest emirp (991 is prime also) that is also an invertible prime, it's 180 degree rotation
(Strobagram)  produces the prime 661. *Prime Curios

199, 211, and 223 are the smallest triple of primes of the form n, n+12 and n+24, and it is the only triple less than 1000. *Prime Curios
go here more Math Facts for every Year Date,

EVENTS

1765 The Board of Longitude appointed Richard Dunthorne to be the first "Comparer of the Ephemeris and Corrector of the Proofs" for the (then still future) Nautical Almanac and Astronomical Ephemeris. *Wik Later there would be a small team of these "computers" creating lunar tables as a potential solution for the "longitude problem", determining longitude at sea. At this time calculator was a term used occasionally for accountants, but more commonly for a book of mathematical tables.One example of such was "The Assistant Calculator, or Cotton Spinners Guide, being a complete set of tables, of the greatest use in the cotton spinning business."

1860  First wet plate photographs of an eclipse; they require 1/30 of the exposure time of a daguerreotype. *NSEC

Photo :Stanford SOLAR Center - History of Solar

1872 Weierstrass, in a lecture to the Berlin Academy, gave his classical example of a continuous nowhere diﬀerentiable function. See Big Kline, p. 956.*VFR

1898 Marie and Pierre Curie discover the previously unknown element Polonium which she named for her home country, Poland. *Brody & Brody, The Science Class You Wished You Had

1979 Great Britain issued a stamp honoring Alice’s Adventures in Wonderland. *VFR

1962 Hearings on Mercury 13 Women suspended. The first potential US women in space, often called the Mercury 13 in comparison to the original Mercury 7 astronauts, had a hearing in congress beginning July 17th. The house convened public hearings before a special Subcommittee on Science and Astronautics. Significantly, the hearings investigated the possibility of gender discrimination two full years before the Civil Rights Act of 1964 made that illegal, making these hearings a marker of how ideas about women's rights permeated political discourse even before they were enshrined in law. The hearings would abruptly be terminated at lunch on the 18th. In less than a year, Soviet cosmonaut Valentina Tereshkova became the first woman in space on June 16, 1963. In response, Clare Boothe Luce published an article in Life criticizing NASA and American decision makers. By including photographs of all thirteen Lovelace finalists, she made the names of all thirteen women public for the first time. (The Time issue is available at Google Books here. Astronaut Sally Ride became the first American woman in space in 1983 on STS-7. *Wik

1968  Intel Founded.  Robert Noyce, Andy Grove and Gordon Moore incorporated Intel, a company they built on production of the microprocessor. The component that has allowed computers to increase in speed and decrease in size, the microprocessor also built Intel, whose Pentium processors now power most IBM-compatible personal computers.

Moore is famous for Moore's Law, which dictates that every 18 months microprocessors double in speed and decrease in size by half.

2014 first "Sun-spotless day" on the Earthward side of sun since 2011, *David Dickinson ‏@Astroguyz

Spaceweather.com reports that today we surpassed the largest number of spotless days (270) of the previous 2008 Solar Minimum cycle. The current spotless streak stands at 33 days and is quite possibly on its way to surpass the previous longest streak of this minimum at 36 days.  And you have to go back to 1913 to find a year that had more spotless days (311)!

You might be wondering: when is the next Solar Maximum?  That’s forecast to be July 2025.  Both the minimum & maximum forecasts have a +/- 6-month error. *The Swinging Post

The blank sun on Dec. 8, 2019. Credit: NASA/Solar Dynamics Observatory

BIRTHS

1013 Hermann of Reichenau (July 18, 1013 – September 24, 1054), was a German mathematician who was important for the transmission of Arabic mathematics, astronomy and scientific instruments into central Europe.*SAU

Blessed Hermann of Reichenau or Herman the Cripple (18 July 1013 – 24 September 1054), also known by other names, was an 11th-century Benedictine monk and scholar. He composed works on history, music theory, mathematics, and astronomy, as well as many hymns. He has traditionally been credited with the composition of "Salve Regina", "Veni Sancte Spiritus", and "Alma Redemptoris Mater", although these attributions are sometimes questioned. His cultus and beatification were confirmed by the Roman Catholic Church in 1863. *Wik

 *stignatiusmobile

1635 Robert Hooke ( 18 July[NS 28 July] 1635 – 3 March 1703) born.English natural philosopher, architect and polymath. His adult life comprised three distinct periods: as a scientific inquirer lacking money; achieving great wealth and standing through his reputation for hard work and scrupulous honesty following the great fire of 1666, but eventually becoming ill and party to jealous intellectual disputes. These issues may have contributed to his relative historical obscurity.
He was at one time simultaneously the curator of experiments of the Royal Society and a member of its council, Gresham Professor of Geometry and a Surveyor to the City of London after the Great Fire of London , in which capacity he appears to have performed more than half of all the surveys after the fire. He was also an important architect of his time, though few of his buildings now survive and some of those are generally misattributed, and was instrumental in devising a set of planning controls for London whose influence remains today. Allan Chapman has characterised him as "England's Leonardo" *wik
He was born in Freshwater, Isle of Wight, and discovered the law of elasticity, known as Hooke's law, and invented the balance spring for clocks. He was a virtuoso scientist whose scope of research ranged widely, including physics, astronomy, chemistry, biology, geology, architecture and naval technology. On 5 Nov 1662, Hooke was appointed the Curator of Experiments at the Royal Society, London. After the Great Fire of London (1666), he served as Chief Surveyor and helped rebuild the city. He also invented or improved meteorological instruments such as the barometer, anemometer, and hygrometer. Hooke authored the influential Micrographia (1665)*TIS

One of my favorites, a louse seems to be marching off to war

1689 Samuel Molyneux (16 July 1689 – 13 April 1728), British astronomer (Royal Observatory at Kew) and politician. Together with assistant James Bradley, he made measurements of aberration - the diversion of light from stars. They made observations of the star Â Draconis with a vertical telescope. Starting in 1725 they had the proof of the movement of the earth giving support to the Copernican model of the earth revolving around the sun. The star oscillated with an excursion of 39 arcsecs between its lowest declination in May and its the highest point of its oscillation in September. He was unfortunate to fall ill in 1728 and into the care of the Anatomist to the Royal Family, Dr Nathaniel St Andre, whose qualifications were as a dancing master. Molyneux died shortly thereafter. *TIS

Molyneux married Lady Elizabeth Capel, daughter of Algernon Capell, 2nd Earl of Essex, on 5 April 1717. In 1728, he suffered a fit while in the House of Commons. He was treated by court anatomist Nathaniel St André, but the treatment did not prove successful, and Molyneux died in Kew in April. On the night of the death, St André eloped with Molyneux's wife, Elizabeth, the two marrying in 1730. Samuel Madden, a relative of Molyneux's, claimed that St André had poisoned the MP. Although St André won an action for defamation, he found himself unable to secure regular work. *Wik

Mary Tofts duping several distinguished surgeons, physicians and male-midwives into believing that she is giving birth to a litter of rabbits. Etching by W. Hogarth, 1726. The male surgeon attending her is Nathaniel St André.

1768 Jean Robert Argand born (July 18, 1768 – August 13, 1822). His single original contribution to mathematics was the invention and elaboration of a geometric representation of complex numbers and operations on them. In this he was preceded by Wessel and followed by Gauss.*VFR Swiss mathematician who was one of the earliest to use complex numbers, which he applied to show that all algebraic equations have roots. He invented the Argand diagram - a geometrical representation of complex numbers as a point with the real portion of the number on the x axis and the imaginary part on the y axis.*Wik

More detail about the history of the diagram here.

1813 Pierre Laurent (July 18, 1813 – September 2, 1854) was a French mathematician best-known for his study of the so-called Laurent Series in Complex analysis. *SAU

The Laurent series is an expansion of a function into an infinite power series, generalizing the Taylor series expansion.*Wik

1853 Antoon Lorentz (18 July 1853 – 4 February 1928) was a Dutch physicist who shared the 1902 Nobel Prize in Physics with Pieter Zeeman for the discovery and theoretical explanation of the Zeeman effect. He also derived the transformation equations subsequently used by Albert Einstein to describe space and time. *Wik
Lorentz is best known for his work on electromagnetic radiation and the FitzGerald-Lorentz contraction. He developed the mathematical theory of the electron.*SAU

1856 Giacinto Morera (Novara, 18 July 1856 – Turin, 8 February 1909), was an Italian engineer and mathematician. He is remembered for Morera's theorem in the theory of functions of a complex variables and for his work in the theory of linear elasticity.

Morera's theorem states that a continuous, complex-valued function f defined on an open set D in the complex plane that satisfies{\displaystyle \oint _{\gamma }f(z)\,dz=0}

for every closed piecewise C1 curve   𝛾{\displaystyle \gamma } in D must be holomorphic on D.

He was member of the Accademia Nazionale dei Lincei (first elected corresponding member on 18 July 1896, then elected national member on 26 August 1907)[20] and of the Accademia delle Scienze di Torino (elected on 9 February 1902).[21] Maggi (1910, p. 317) refers that also the Kharkov Mathematical Society elected him corresponding member during the meeting of the society held on 31 October 1909 (Old Calendar), being apparently not aware of his death.*Wik

1891 Emil Julius Gumbel (18 July 1891, in Munich – 10 September 1966, in New York City) was an American mathematician and statistician is known for his work in reliability theory and order statistics. His name remains on the Type 1 extreme value distribution, known as the Gumbel distribution. In his early life, during WW I, he militantly advocated for pacifism. Gumbel acted as a historian and statistician recording the political murders in the early Weimar Republic. His activities caused ostracization and political harassment. When he moved to France (1932), he could better concentrate on his mathematical work, most notably examining the statistical distributions most used by actuaries. He also applied his skills in the fields of hydrology (floods) and meteorology (drought). Eight years later, due to WW II, he moved to the U.S. (1940) and continue this work. *TiS

1899 Robert Schlapp (18 July 1899 in Edinburgh, Scotland - 31 May 1991 in Ashford, Kent, England)studied at Edinburgh and Cambridge universities. He spent his whole career at Edinburgh University teaching mathematics and Physics. He was also interested in the History of Mathematics. He became President of the EMS in 1942 and 1943. *SAU

1906 Edwin Ford Beckenbach (July 18, 1906 – September 5, 1982) was an American mathematician

In 1929 he earned a master's degree at Rice University, and in 1931 a PhD under the direction of Lester R. Ford. As a postdoc, he was a National Research Fellow at Princeton University, Ohio State University, and the University of Chicago.

At UCLA, he led the development of the graduate program in mathematics. The first mathematics PhD was granted under his direction as thesis advisor.

Beckenbach was also a leader in the founding (in 1948) of the Institute of Numerical Analysis, which was then a branch of the National Bureau of Standards. His institute developed in 1948 and 1949 a vacuum-tube computer (SWAC), which began operation in July 1950 and was for a short time the fastest computer in the world. In 1974 he retired from UCLA as professor emeritus. From 1949 to 1963, he was a consultant for the Rand Corporation and in the academic year 1951/1952 he was a visiting professor at the Institute for Advanced Study.

In the academic year 1958/59 he was a Guggenheim Fellow at ETH Zürich. With František Wolf, Beckenbach founded in 1951 the Pacific Journal of Mathematics, of which he was the first editor. In 1983, he received the Distinguished Service Award from the Mathematical Association of America. The Beckenbach Book Prize, first awarded in January 1985, is named in his honor. *Wik

1922 Thomas S(amuel) Kuhn (July 18, 1922 – June 17, 1996) was an American historian of science, MIT professor, noted for The Structure of Scientific Revolutions (1962), one of the most influential works of history and philosophy written in the 20th century. His thesis was that science was not a steady, cumulative acquisition of knowledge, but it is "a series of peaceful interludes punctuated by intellectually violent revolutions." Then appears a Lavoisier or an Einstein, often a young scientist not indoctrinated in the accepted theories, to sweep the old paradigm away. Such revolutions, he said, came only after long periods of tradition-bound normal science. "Frameworks must be lived with and explored before they can be broken," *TIS This was the first modern use of the term "paradigm" in this way.

1939 Marjorie Lee Senechal (née Wikler,July 18,1939 - ) is an American mathematician and historian of science, the Louise Wolff Kahn Professor Emerita in Mathematics and History of Science and Technology at Smith College and editor-in-chief of The Mathematical Intelligencer. In mathematics, she is known for her work on tessellations and quasicrystals; she has also studied ancient Parthian electric batteries and published several books about silk.

Senechal won the Mathematical Association of America's Carl B. Allendoerfer Award for excellence in expository writing in Mathematics Magazine in 1982, for her article, "Which Tetrahedra Fill Space?" In 2008, her book American Silk 1830 – 1930 won the Millia Davenport Publication Award of the Costume Society of America. In 2012, she became a fellow of the American Mathematical Society.

Her Homepage at Smith is here

1948 Hartmut Michel (German pronunciation: [18 July, 1948 - ) is a German biochemist, who received the 1988 Nobel Prize,along with Johann Deisenhofer and Robert Huber, in Chemistry for determination of the first crystal structure of an integral membrane protein, a membrane-bound complex of proteins and co-factors that is essential to photosynthesis.

They are the first to succeed in unraveling the full details of how a membrane-bound protein is built up, revealing the structure of the molecule atom by atom. The protein is taken from a bacterium which, like green plants and algae, uses light energy from the sun to build organic substances. All our nourishment has its origin in this process, which is called photosynthesis and which is a condition for all life on earth.*TiS

DEATHS

1650 Christoph Scheiner SJ (25 July 1573 (or 1575) – 18 July 1650) was a Jesuit priest, physicist and astronomer in Ingolstadt. In 1603, Scheiner invented the pantograph, an instrument which could duplicate plans and drawings to an adjustable scale. Later in life he would invent a sunspot viewing appartus. In 1611, Scheiner observed sunspots; in 1612 he published the "Apelles letters" in Augsburg. Marcus Welser had the first three Apelles letters printed in Augsburg on January 5, 1612. They provided one of many reasons for the subsequent unpleasant argument between Scheiner and Galileo Galilei. *Wik Thus, in 1614, Galileo found himself in an unresoved dispute over priority with a mean and determined Jesuit. The fight was to grow meaner in subsequent years. It would play a major role in Galileo's Inquisitional trial eighteen years later. *James Reston, Jr., Galileo: A Life

Sunspots observed and drawn in October, 1611, engraving by Alexander Mair, in Christoph Scheiner, Tres epistolae de maculis solaribus, in Galileo Galilei, Istoria e dimostrazioni intorno alle macchie solari, 1613 (Linda Hall Library)

1742 Abraham Sharp (1653– 18 July 1742) was an English mathematician who worked with Flamsteed. He calculated π to 72 places (using an arcsine sequence, briefly holding the record until John Machin calculated 100 digits in 1706).*SAU

1807 Thomas Jones (23 June 1756 – 18 July 1807) was Head Tutor at Trinity College, Cambridge for twenty years and an outstanding teacher of mathematics. He is notable as a mentor of Adam Sedgwick.
He was born at Berriew, Montgomeryshire, in Wales. On completing his studies at Shrewsbury School, Jones was admitted to St John's College, Cambridge on 28 May 1774, as a 'pensioner' (i.e. a fee-paying student, as opposed to a scholar or sizar). He was believed to be an illegitimate son of Mr Owen Owen, of Tyncoed, and his housekeeper, who afterwards married a Mr Jones, of Traffin, County Kerry, Thomas then being brought up as his son.
On 27 June 1776, Jones migrated from St John's College to Trinity College. He became a scholar in 1777 and obtained his BA in 1779, winning the First Smith's Prize and becoming Senior Wrangler. In 1782, he obtained his MA and became a Fellow of Trinity College in 1781. He became a Junior Dean, 1787–1789 and a Tutor, 1787-1807. He was ordained a deacon at the Peterborough parish on 18 June 1780. Then he was ordained priest, at the Ely parish on 6 June 1784, canon of Fen Ditton, Cambridgeshire, in 1784, and then canon of Swaffham Prior, also 1784. On 11 December 1791, he preached before the University, at Great St Mary's, a sermon against duelling (from Exodus XX. 13), which was prompted by a duel that had lately taken place near Newmarket between Henry Applewhaite and Richard Ryecroft, undergraduates of Pembroke, in which the latter was fatally wounded. Jones died on 18 July 1807, in lodgings in Edgware Road, London. He is buried in the cemetery of Dulwich College. A bust and a memorial tablet are in the ante-chapel of Trinity College. *Wik

1930 Karl Emmanuel Robert Fricke (September 24, 1861 in Helmstedt, Germany ; July 18, 1930 in Bad Harzburg, Germany) was a German mathematician, known for his work in function theory, especially on elliptic, modular and automorphic functions. He was one of the main collaborators of Felix Klein, with whom he produced two classic two volume monographs on elliptic modular functions and automorphic functions.

In 1893 in Chicago, his paper Die Theorie der automorphen Functionen und die Arithmetik was read (but not by Fricke) at the International Mathematical Congress held in connection with the World's Columbian Exposition. From 1894 to 1930 Fricke was professor of Higher Mathematics at the Technische Hochschule Carolo-Wilhelmina in Braunschweig.*Wik

1977 Georgi Delchev Bradistilov (25 October 1904 [12 October 1904 O.S.] – 18 June 1977) was a Bulgarian mathematician.

He attended 3rd Sofia gymnasium and in 1922 entered Sofia University to study physics and mathematics. In 1927 he graduated with honors and the same year was appointed as assistant professor in mathematics. In the 1930s he studied at the University of Paris and the University of Munich. Bradistilov was one of the last students to take Arnold Sommerfeld's course in theoretical physics before his retirement. In 1938, he defended his doctorate, with Oskar Perron as advisor, at the University of Munich.

Georgi Bradistilov's contributions to applied mathematics are related to nonlinear differential equations and their applications to mechanics and electrotechnics, to electrostatic potential, to nonlinear oscillations.

He was notorious for his sense of humor and openness, for his love of arts and nature as well as for his refined taste, his wife being an artist educated in Florence.(QED?)

During his lifetime Georgi Bradistilov received many Bulgarian state decorations and awards. Recently a street in Sofia near the Technical University was named after him. *Wik

2018 Burton Richter (22 Mar 1931, ) American physicist who was jointly awarded the 1976 Nobel Prize for Physics with Samuel C.C. Ting for the discovery of a new subatomic particle, the J/psi particle. *TIS He led the Stanford Linear Accelerator Center (SLAC) team which co-discovered the J/ψ meson in 1974, alongside the Brookhaven National Laboratory (BNL) team led by Samuel Ting. This discovery was part of the so-called November Revolution of particle physics. He was the SLAC director from 1984 to 1999.*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