Monday 29 April 2024

An Unusual Prime Series



 I found this in an article in The American Mathematical Monthly  Vol. 1, No. 6, Jun., 1894.  The article is taken from a paper by J. W. NICHOLSON., President and Professor of Mathematics at Louisiana State University.


To keep it simple I will present a very small example of the professor's theorem.

Pick a prime number, p (I'll use five because it keeps things short and easy) .

Now take the sum of the squares of every  integer smaller than p and "voila", it is divisible by p

42 + 32 + 22 + 12 = 30, which is divisible by 5.

and it doesn't have to be a square, the same series using cubes  gives:
43 + 33 + 23 + 13 = 100, which is also divisible by 5.

In general, the first baby rule says for prime p, (p-1)n + (p-2) n + ... + 1n will be divisible by p as for any power n smaller than p.

Go ahead, try a few of your own.

Now to kick it up a little... let's add in any constant, c,  to the mix.
It is also true, that for prime p and n smaller than p:

(c+p-1)n+(c+p-2)n ...... + (c+0)n will also be divisible by p.

If I keep p = 5 and use c=2 the series would be :
(2+4)2+(2+3)2++(2+2)2+(2+1)2  + (2+0)2 =90  which is still divisible by 5.

Ok, and one to grow on:  you can use a constant multiplier in front of the p-x terms... for example using a multiplier of three in each case we have
(2+3x4)2+(2+3x3)2+(2+3x2)2+(2+3x1)2  + (2+0)2 =410 which is still divisible by 5.
According to the Professor, this works only if, we use a prime p, As pointed out in the comments, there are some primes for which this is not true (and some non primes for which it is true in at least one of the versions described.    I originally misstated  what he wrote.  
No justification was given, and I could provide none, but the brilliant Joshua Zucker sent a few guidelines to assist:
The group of units mod p is cyclic.

So we are summing 1 through p-1, which for p odd, means we have 0 mod p.

Now, any odd power won't cause a problem because we can still pair x with -x to get a sum of 0.

I think we can deal with all the powers by viewing all the numbers as powers of some generator mod p, but I'm too lazy to work out the details.

Anyway, the point of the group being cyclic mod p is that your addition of a constant and multiplication by a constant leaves your numbers the same mod p, so the second half of things is pretty much doing nothing.

On This Day in Math - April 29

 


Science is built up of facts, as a house is with stones.
But a collection of facts is no more a science
than a heap of stones is a house.

~Henri Poincare

The 119th day of the year; the largest amount of US money one can have in coins without being able to make change for a dollar is 119 cents. *Tanya Khovanova, Number Gossip

119 is the product of the first two primes ending with 7

119 is the sum of five consecutive primes (17 + 19 + 23 + 29 + 31).

119 is the order of the largest cyclic subgroups of the Monster group.

There are 119 prime numbers which gets displayed on a 12-hour digital clock.

119 is the smallest composite number, and the only year date, that is one less than a factorial.  The next will be 40319 = 8! - 1.  (students might examine the sequence of n! + 1 for patterns)

119 is a Perrin Number, A Fibonacci like sequence that begins with 3, 0, 2 and then each new value is the sum of the two digits before the last known, so it starts 3, 0, 2, 3, 2, 5, 5, 7, ...  The name is for French mathematician Francois Perrin who wrote about it in 1899,





EVENTS

1657 Christiaan Huygens published De Ratiociniis in Ludo Aleae [Reasoning in games of chance] on the calculus of probabilities, the first printed work on the subject.  

John Arbuthnot  translated Huygens' "De ratiociniis in ludo aleae " in 1692 and extended it by adding a few further games of chance. This was the first work on probability published in English.



In 1699, the French Academy of Sciences held its first public meeting, in the Louvre. *TIS


1756 Benjamin Franklin was elected a Fellow of the Royal Society on April 29, 1756. Under the rules candidates had to be recommended in writing by three or more Fellows acquainted with him “either in person or by his Works,” the recommendation had to be approved by the Council, and the certificate publicly displayed at “ten several ordinary meetings” before balloting. Nothing more was required of foreign fellows. British (including colonial) fellows, however, had to pay an admission fee (five guineas after 1752) and a sum of £21 “for the use of the Society in lieu of Contributions,” or give bond for that amount. Only then was a British subject deemed to be a fellow and entitled to be registered in the Journal-Book and be included in the printed List of Fellows. To attend meetings and vote in elections British fellows had also to sign the obligation to “endeavor to promote the Good of the Royall Society … and to pursue the Ends for which the same was formed.” *Franklin Papers, Natl. Archives


1831 Wilhelm Eduard Weber is offered the position of full professor of Physics at Gottingen to fill the position of Tobias Mayer, partially on the recommendation of Gauss.

In December 1837, the Hanoverian government dismissed Weber, one of the Göttingen Seven(a group of seven liberal professors at University of Göttingen. In 1837, they protested against the annullment of the constitution of the Kingdom of Hanover by its new ruler, King Ernest Augustus, and refused to swear an oath to the king.),  from his post at the university for political reasons. Weber then travelled for a time, visiting England, among other countries, and became professor of physics in Leipzig from 1843 to 1849, when he was reinstated at Göttingen. One of his most important works, co-authored with Carl Friedrich Gauss and Carl Wolfgang Benjamin Goldschmidt, was Atlas des Erdmagnetismus: nach den Elementen der Theorie entworfen (Atlas of Geomagnetism: Designed according to the elements of the theory), a series of magnetic maps, and it was chiefly through his efforts that magnetic observatories were instituted. He studied magnetism with Gauss, and during 1864 published his Electrodynamic Proportional Measures containing a system of absolute measurements for electric currents, which forms the basis of those in use. Weber died in Göttingen, where he is buried in the same cemetery as Max Planck and Max Born.*Wik 

Together with Gauss, he invented the magnetic telegraph in 1833, which connected the observatory with the institute for physics in Göttingen.





1832 Evariste Galois released from prison. On (1831)Bastille Day, Galois was at the head of a protest, wearing the uniform of the disbanded artillery, and came heavily armed with several pistols, a rifle, and a dagger. For this, he was again arrested and this time sentenced to six months in prison for illegally wearing a uniform. He was released on April 29, 1832. During his imprisonment, he continued developing his mathematical ideas.*Wik (He will be shot on the morning of May 30, and die the next day, 1832)

The Galois memorial in the cemetery of Bourg-la-Reine. Évariste Galois was buried in a common grave and the exact location is unknown.






1854 Lincoln University, the first university for Blacks, is incorporated. Lincoln University of the Commonwealth of Pennsylvania was chartered in April 1854 as Ashmun Institute. As Horace Mann Bond, '23, the eighth president of Lincoln University, so eloquently cites in the opening chapter of his book, Education for Freedom, this was "the first institution found anywhere in the world to provide a higher education in the arts and sciences for male youth of African descent." The story of Lincoln University goes back to the early years of the 19th century and to the ancestors of its founder, John Miller Dickey, and his wife, Sarah Emlen Cresson. The Institute was re-named Lincoln University in 1866 after President Abraham Lincoln. *Lincoln University web site

Lincoln University has numerous notable alumni, including US Supreme Court Justice Thurgood Marshall; Harlem Renaissance poet Langston Hughes; Medal of Honor recipient and pioneering African-American editor Christian Fleetwood; former US Ambassador to Botswana, Horace Dawson; civil rights activist Frederick D. Alexander; the first president of Nigeria, and Nnamdi Azikiwe; the first president of Ghana

Student Union, Lincoln University.





1901 Math Blunder succeeds, "But a more recent, a veritably shocking, example is at hand. On April 29, 1901, a Mr. Israel Euclid Eabinovitch submitted to the Board of University Studies of the Johns Hopkins University, in conformity with the requirements for the degree of doctor of philosophy, a dissertation in which, after an introduction full of the most palpable blunders, he proceeds to persuade himself that he proves Euclid's parallel postulate by using the worn-out device of attacking it from space of three dimensions, a device already squeezed dry and discarded by the very creator of non-Euclidean geometry, Janos Bolyai. And his dissertation was accepted by the referees. (Science Monthly, Vol 67, page 642)






In 1878, “a monument, in memory of the great physicist, Alessandro Volta, was unveiled at Pavia. Most of the Italian Universities, and several foreign scientific societies had sent deputies to Pavia University for this event. The monument is a masterpiece of the sculptor Tantardini of Milan. The ceremony of unveiling was followed by a dignified celebration at the University, and upon that occasion the following gentlemen were elected honorary doctors of the scientific faculty: Professors Clerk Maxwell (Cambridge) and Sir W. Thomson (Glasgow); M. Dumas (Paris), Dr. W. E. Weber (Leipzig); Professors Bunsen (Heidelberg) and Helmholtz (Berlin), Dr. F. H. Neumann (Koenigsberg), and Dr. P. Riess (Berlin).”*TIS


1925 The first woman, F. R. Sabin, is elected to the National Academy of Sciences (Kane, p. 945). *VFR She was a histology professor at Johns Hopkins University. 

Julia Robinson was the first woman to serve as president of the American Mathematical Society, and was also the first woman mathematician to be elected to the U.S. National Academy of Sciences, in 1975. 


1931 Robert Lee Moore elected to the National Academy of Sciences. *VFR



BIRTHS

1667 John Arbuthnot (baptised April 29, 1667 – February 27, 1735), fellow of the Royal College of Physicians. In 1710, his paper “An argument for divine providence taken form the constant regularity observ’s in the bith of both sexes” gave the first example of statistical inference. In his day he was famous for his political satires, from which we still know the character John Bull. *VFR
He inspired both Jonathan Swift's Gulliver's Travels book III and Alexander Pope's Peri Bathous, Or the Art of Sinking in Poetry, Memoirs of Martin Scriblerus,m (Wikipedia) He also translated Huygens' "De ratiociniis in ludo aleae " in 1692 and extended it by adding a few further games of chance. This was the first work on probability published in English.*SAU   

Also known for his statistical analysis of the male and female birth rates in England. This is probably the first use of probability in a social statistical analysis and the earliest case of a statistical significance test.  *RMAT

"He also contributed to the development of archaeology and history with his papers on Tables of Grecian, Roman, and Jewish measures, weights and coins; reduced to the English standard.” Title page from my 1705, first edition copy of this publication by John Arbuthnot." *coffeefueled



1850 William Edward Story (April 29, 1850 in Boston, Massachusetts, U.S. - April 10, 1930 in Worcester, Massachusetts, U.S.) He taught at Johns Hopkins with Sylvester and then moved on to Clark University which was, during the early 1890’s, the strongest mathematics department in the country. In the 1890’s he edited the short lived Mathematical Reviews.*VFR




1854 Jules Henri Poincare (29 April 1854 – 17 July 1912) born in Nancy, France. He did important work in function theory, alge­braic geometry, number theory, algebra, celestial mechanics, differential equations, mathematical physics, algebraic topology, and philosophy of mathematics. There may never be another universal mathematician like Poincar´e. *VFR His Poincaré Conjecture holds that if any loop in a given three-dimensional space can be shrunk to a point, the space is equivalent to a sphere. Its proof remains an unsolved problem in topology. He influenced cosmogony, relativity, and topology. In applied mathematics he also studied optics, electricity, telegraphy, capillarity, elasticity, thermodynamics, potential theory, quantum theory, and cosmology. He is often described as the last universalist in mathematics. He studied the three-body-problem in celestial mechanics, and theories of light and electromagnetic waves. He was a co-discoverer (with Albert Einstein and Hendrik Lorentz) of the special theory of relativity. *TIS




1872 Forest Ray Moulton (29 Apr 1872 (in a log cabin near the small town of Leroy, Michigan); 7 Dec 1952 at age 80) American astronomer who collaborated with Thomas Chamberlin in advancing the planetesimal theory of the origin of the solar system (1904). They suggested filaments of matter were ejected when a star passed close to the Sun, which cooled into tiny solid fragments, “planetesimals.” Over a very long period, grains collided and stuck together. Continued accretion created pebbles, boulders, and eventually larger bodies whose gravitational force of attraction accelerated the formation of protoplanets. (This formation by accretion is still accepted, but not the stellar origin of the planetesimals.) Moulton was first to suggest that the smaller satellites of Jupiter discovered by Nicholson and others in the early 20th century were captured asteroids, now widely accepted. *TIS



1894 Marietta Blau (29 April 1894 – 27 January 1970) was an Austrian physicist credited with developing photographic nuclear emulsions that were usefully able to image and accurately measure high-energy nuclear particles and events, significantly advancing the field of particle physics in her time. For this, she was awarded the Lieben Prize by the Austrian Academy of Sciences. As a Jew, she was forced to flee Austria when Nazi Germany annexed it in 1938, eventually making her way to the United States. She was nominated for Nobel Prizes in both physics and chemistry for her work, but did not win. After her return to Austria, she won the Erwin Schrödinger Prize from the Austrian Academy of Sciences. *Wik 

Austrian nuclear physicist who began as a strong student in mathematics and physics at school, and studied physics at university, where she wrote her thesis on the absorption of gamma rays (1919). At first, she took a job (1921) with a manufacturer of x-ray tubes in Berlin. By 1923, she progressed to researching radioactivity with the Institut für Radiumforschung back in Vienna. There she developed the photographic emulsion technique for the study of nuclear disintegration caused by cosmic rays, and contributed to development of photomultiplier tubes. Blau was first to use nuclear emulsions to detect neutrons by observing recoil protons. Albert Einstein recognized her as a very capable experimental physicist, and after 1938 when she fled the rise of the Nazis, Einstein helped her career continue in Mexico City and then the U.S. *TIS




1906 Eugène Ehrhart (29 April 1906 Guebwiller – 17 January 2000 Strasbourg) was a French mathematician who introduced Ehrhart polynomials in the 1960s. Ehrhart received his high school diploma at the age of 22. He was a mathematics teacher in several high schools, and did mathematics research on his own time. He started publishing in mathematics in his 40s, and finished his PhD thesis at the age of 60. The theory of Ehrhart polynomials can be seen as a higher-dimensional generalization of Pick's theorem. *Wik




1926 Vera Nikolaevna Maslennikova (29 April 1926, Priluki, Russia - 14 August 2000) Gelfond supervised her diploma work at Moscow and Sobolev directed her Ph.D. at the Steklov Mathematical Institute. She has published more than 80 papers in the theory of partial differential equations, the mathematical hydrodynamics of rotating fluids, and in function spaces.*VFR She has worked in the field of partial differential equations, the mathematical hydrodynamics of rotating fluids, and in function spaces, having published more than one hundred and forty research papers. *Wik




1928 Laszlo Belady,( April 29, 1928 in Budapest - November 6, 2021) creator of the Belady algorithm (used in optimizing the performance of computers), is born. Belady worked at IBM for 23 years in software engineering before joining the Mitsubishi Electronics Research Laboratory in the mid-1980s. He wins numerous awards, including the J.D. Warnier Prize for Excellence in Information and an IEEE fellowship. *CHM




1930 Yuan Wang (29 April 1930 in Lanhsi, Zhejiang province, China - 14 May 2021) )Most of Wang Yuan's research has been in the area of number theory. He looked at sieve methods and applied them to the Goldbach Conjecture. He also applied circle methods to the Goldbach Conjecture. In 1956 he published (in Chinese) On the representation of large even integer as a sum of a prime and a product of at most 4 primes in which he assumed the truth of the Riemann hypothesis and with that assumption proved that every large even integer is the sum of a prime and of a product of at most 4 primes. He also proved that there are infinitely many primes p such that p + 2 is a product of at most 4 primes. In 1957 Wang Yuan published four papers: On sieve methods and some of their applications; On some properties of integral valued polynomials; On the representation of large even number as a sum of two almost-primes; and On sieve methods and some of the related problems.*SAU





1936 Volker Strassen
 (April 29, 1936 - ) is a German mathematician, a professor emeritus in the department of mathematics and statistics at the University of Konstanz. Strassen began his researches as a probabilist; his 1964 paper An Invariance Principle for the Law of the Iterated Logarithm defined a functional form of the law of the iterated logarithm, showing a form of scale invariance in random walks. This result, now known as Strassen's invariance principle or as Strassen's law of the iterated logarithm, has been highly cited and led to a 1966 presentation at the International Congress of Mathematicians.
In 1969, Strassen shifted his research efforts towards the analysis of algorithms with a paper on Gaussian elimination, introducing Strassen's algorithm, the first algorithm for performing matrix multiplication faster than the O(n3) time bound that would result from a naive algorithm. In the same paper he also presented an asymptotically-fast algorithm to perform matrix inversion, based on the fast matrix multiplication algorithm. This result was an important theoretical breakthrough, leading to much additional research on fast matrix multiplication, and despite later theoretical improvements it remains a practical method for multiplication of dense matrices of moderate to large sizes. In 1971 Strassen published another paper together with Arnold Schönhage on asymptotically-fast integer multiplication based on the fast Fourier transform; see the Schönhage–Strassen algorithm. Strassen is also known for his 1977 work with Robert M. Solovay on the Solovay–Strassen primality test, the first method to show that testing whether a number is prime can be performed in randomized polynomial time and one of the first results to show the power of randomized algorithms more generally.*Wik





DEATHS

1633 Francis Godwin, an English cleric, was buried Apr. 29, 1633, at about age 71. As Bishop of Hereford, Godwin published a number of mainstream theological tracts, but he left behind at his death a manuscript about a fantasy voyage undertaken by a Spaniard, Domingo Gonsales. While at the island of St. Helena, Gonsales had discovered a species of wild swans, which he called “gansa” and which he discovered could be trained to fly in harness and carry a load. He rigged up an aerial chariot, hooked 25 gansas to it, and off he flew on a brief test flight. He was picked up on St. Helena by a ship from the Indies, and he persuaded the captain to make room for the swans and the chariot. When the ship was attacked by pirates off the Canaries, Gonsales climbed in his gondola, hooked up the gansas, and escaped. But the gansas had minds of their own, and kept flying up and up, until they ultimately escaped the force of the earth’s gravity (an interesting notion, because in 1630, no one believed in a force of gravity). Eventually, they reached the Moon, where Gonsales discovered that the Moon is inhabited by a race of peaceful giants, who swooned when they heard the name “Jesus” and converted instantly to Christianity.

It was a wonderful tale, and it could have been buried with the bishop, but it was salvaged and published in 1638 as The Man in the Moone: or, A Discourse of a Voyage Thither, with a wonderful frontispiece showing Gonsales in his gansa-powered flying machine. This first edition is very scarce (four known copies), but it was republished in 1657, and also translated into French in 1648; we were very fortunate to acquire a 1666 edition of the French translation just last year. It includes the charming illustration of the “little goose coupe”, as well as a depiction of the language of the Lunarians, which is sung without words (the second tune is lunar for “Gonsales”).

If you look closely at the publication date, you have the rare chance to see the first 7 Roman numerals in ascending order, starting from the right. This is one of the reasons why the year 1666 was feared as an annus mirabilis by the English, a fear not disproved by the arrival of the bubonic plaque and the Great Fire of London. *LH




1713 Francis Hauksbee the elder (baptized on 27 May 1660 in Colchester–buried in St Dunstan's-in-the-West, London on 29 April 1713.), also known as Francis Hawksbee, was an 18th-century English scientist best known for his work on electricity and electrostatic repulsion.
Initially apprenticed in 1678 to his elder brother as a draper, Hauksbee became Isaac Newton’s lab assistant. In 1703 he was appointed curator, instrument maker and experimentalist of the Royal Society by Newton, who had recently become president of the society and wished to resurrect the Royal Society’s weekly demonstrations.
Until 1705, most of these experiments were air pump experiments of a mundane nature, but Hauksbee then turned to investigating the luminosity of mercury which was known to emit a glow under barometric vacuum conditions.
By 1705, Hauksbee had discovered that if he placed a small amount of mercury in the glass of his modified version of Otto von Guericke's generator, evacuated the air from it to create a mild vacuum and rubbed the ball in order to build up a charge, a glow was visible if he placed his hand on the outside of the ball. This glow was bright enough to read by. It seemed to be similar to St. Elmo's Fire. This effect later became the basis of the gas-discharge lamp, which led to neon lighting and mercury vapor lamps. In 1706 he produced an 'Influence machine' to generate this effect. He was elected a Fellow of the Royal Society the same year.

Hauksbee continued to experiment with electricity, making numerous observations and developing machines to generate and demonstrate various electrical phenomena. In 1709 he published Physico-Mechanical Experiments on Various Subjects which summarized much of his scientific work.
In 1708, Hauksbee independently discovered Charles' law of gases, which states that, for a given mass of gas at a constant pressure, the volume of the gas is proportional to its temperature.
The Royal Society Hauksbee Awards, awarded in 2010, were given by the Royal Society to the “unsung heroes of science, technology, engineering and mathematics.” *Wik


1862 John Edward Campbell (27 May 1862, Lisburn, Ireland – 1 October 1924, Oxford, Oxfordshire, England) is remembered for the Campbell-Baker-Hausdorff theorem which gives a formula for multiplication of exponentials in Lie algebras. *SAU His 1903 book, Introductory Treatise on Lie's Theory of Finite Continuous Transformation Groups, popularized the ideas of Sophus Lie among British mathematicians.
He was elected a Fellow of the Royal Society in 1905, and served as President of the London Mathematical Society from 1918 to 1920. *Wik  *Renaissance Mathematicus




1864 Charles-Julien Brianchon (19 Dec 1783, 29 Apr 1864 at age 80) French mathematician who published a geometrical theorem (named as Brianchon's theorem) while a student (1806). He showed that in any hexagon formed of six tangents to a conic, the three diagonals meet at a point. (Conics include circles, ellipses, parabolas, and hyperbolas.) In fact, this theorem is simply the dual of Pascal's theorem which was proved in 1639. After graduation, Brianchon became a lieutenant in artillery fighting in Napoleon's army until he left active service in 1813 due to ill health. His last work in mathematics made the first use of the term "nine-point circle." By 1823, Brianchon's interests turned to teaching and to chemistry. *TIS


1872 Jean-Marie-Constant Duhamel (5 Feb 1797, 29 Apr 1872 at age 75) French mathematician and physicist who proposed a theory dealing with the transmission of heat in crystal structures based on the work of the French mathematicians Jean-Baptiste-Joseph Fourier and Siméon-Denis Poisson. *TIS


1894 Giuseppe Battaglini (11 Jan 1826 in Naples, Kingdom of Naples and Sicily (now Italy) - 29 Apr 1894 in Naples, Italy ) Some of Battaglini's results have proved significant. For example, in his doctoral dissertation of 1868, Klein introduced a classification scheme for second-degree line complexes based on Battaglini's earlier work. However, his main importance is his modern approach to mathematics which played a major role in invigorating the Italian university system, particularly in his efforts to bring the non-Euclidean geometry of Lobachevsky and Bolyai to the Italian speaking world. Jules Hoüel played a similar role for non-Euclidean geometry in the French speaking world and the correspondence between the two (see [6]) provides a vivid picture of the reactions of both the French and the Italian mathematical communities against the non-Euclidean geometries. Battaglini and Hoüel also exchanged ideas relating to mathematical education in various European countries. In particular they debated the use of Euclid's Elements as a textbook for teaching elementary geometry in schools. *SAU




1916 – Jørgen Pedersen Gram (June 27, 1850 – April 29, 1916) was a Danish actuary and mathematician who was born in Nustrup, Duchy of Schleswig, Denmark and died in Copenhagen, Denmark.
Important papers of his include On series expansions determined by the methods of least squares, and Investigations of the number of primes less than a given number. The mathematical method that bears his name, the Gram–Schmidt process, was first published in the former paper, in 1883. The Gramian matrix is also named after him.
For number theorists his main fame is the series for the Riemann zeta function (the leading function in Riemann's exact prime-counting function). Instead of using a series of logarithmic integrals, Gram's function uses logarithm powers and the zeta function of positive integers. It has recently been supplanted by a formula of Ramanujan that uses the Bernoulli numbers directly instead of the zeta function.
Gram was the first mathematician to provide a systematic theory of the development of skew frequency curves, showing that the normal symmetric Gaussian error curve was but one special case of a more general class of frequency curves.
He died after being struck by a bicycle.*Wik




1951 Ludwig Josef Johann Wittgenstein (26 April 1889 – 29 April 1951) was an Austrian-British philosopher who worked primarily in logic, the philosophy of mathematics, the philosophy of mind, and the philosophy of language. He was professor in philosophy at the University of Cambridge from 1939 until 1947. In his lifetime he published just one book review, one article, a children's dictionary, and the 75-page Tractatus Logico-Philosophicus (1921). In 1999 his posthumously published Philosophical Investigations (1953) was ranked as the most important book of 20th-century philosophy, standing out as "...the one crossover masterpiece in twentieth-century philosophy, appealing across diverse specializations and philosophical orientations". Bertrand Russell described him as "the most perfect example I have ever known of genius as traditionally conceived, passionate, profound, intense, and dominating". *Wik He died three days after his birthday. He is buried in a cemetery off Huntington Road in Cambridge, UK.



1966 William Henry Eccles FRS (23 August 1875 – 29 April 1966) British physicist who pioneered in the development of radio communication. He was an early proponent of Oliver Heaviside's theory that an upper layer of the atmosphere reflects radio waves, thus enabling their transmission over long distances. He also suggested in 1912 that solar radiation accounted for the differences in wave propagation during the day and night. He experimented with detectors and amplifiers for radio reception, coined the term "diode," and studied atmospheric disturbances of radio reception. After WW I, he made many contributions to electronic circuit development, including the Eccles-Jordan "flip-flop" patented in 1918 and used in binary counters (working with F.W. Jordan).* *TIS




1970 Paul Finsler (born 11 April 1894, in Heilbronn, Germany,- 29 April 1970 in Zurich, Switzerland)Finsler did his undergraduate studies at the Technische Hochschule Stuttgart, and his graduate studies at the University of Göttingen, where he received his Ph.D. in 1919 under the supervision of Constantin Carathéodory. He joined the faculty of the University of Zurich in 1927, and was promoted to ordinary professor there in 1944.

Finsler's thesis work concerned differential geometry, and Finsler spaces were named after him by Élie Cartan in 1934. The Hadwiger–Finsler inequality, a relation between the side lengths and area of a triangle in the Euclidean plane, is named after Finsler and his co-author Hugo Hadwiger. Finsler is also known for his work on the foundations of mathematics, developing a non-well-founded set theory with which he hoped to resolve the contradictions implied by Russell's paradox.
In mathematics, the Hadwiger–Finsler inequality is a result on the geometry of triangles in the Euclidean plane, named after the mathematicians Hugo Hadwiger and Paul Finsler. It states that if a triangle in the plane has side lengths ab and c and area A, then

a^{2} + b^{2} + c^{2} \geq (a - b)^{2} + (b - c)^{2} + (c - a)^{2} + 4 \sqrt{3} A \quad \mbox{(HF)}.

Weitzenböck's inequality is a straightforward corollary of the Hadwiger–Finsler inequality: if a triangle in the plane has side lengths ab and c and area A, then

a^{2} + b^{2} + c^{2} \geq 4 \sqrt{3} A \quad \mbox{(W)}.

Weitzenböck's inequality can also be proved using Heron's formula, by which route it can be seen that equality holds in (W) if and only if the triangle is an equilateral triangle, i.e. a = b = c.
*Wik


2008 Mary Golda Ross (August 9, 1908 – April 29, 2008) was the first known Native American female engineer, and the first female engineer in the history of Lockheed. She was one of the 40 founding engineers of the renowned and highly secretive Skunk Works project at Lockheed Corporation. She worked at Lockheed from 1942 until her retirement in 1973, where she was best remembered for her work on aerospace design – including the Agena Rocket program – as well as numerous "design concepts for interplanetary space travel, crewed and uncrewed Earth-orbiting flights, the earliest studies of orbiting satellites for both defense and civilian purposes." In 2018, she was chosen to be depicted on the 2019 Native American $1 Coin by the U.S. Mint celebrating American Indians in the space program. *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

Sunday 28 April 2024

On This Day in Math - April 28

  




 
One of the principal objects of theoretical research
in my department of knowledge
is to find the point of view from which
the subject appears in its greatest simplicity.
Willard Gibbs (1839 - 1903)


The 118th day of the year. 118 is the smallest n such that the range n, n + 1, ... 4n/3 contains at least one prime from each of these forms: 4x + 1, 4x - 1, 6x + 1 and 6x - 1.

There are four unique partitions of 118 into three integers that all have the same product.  No smaller example exists.  14 × 50 × 54 = 15 × 40 × 63 = 18 × 30 × 70 = 21 × 25 × 72 = 37800.

118 plus the sum of its digits is a power, 2^7

And there are 118 partitions of the number 16.

118 in base six is "Pi-like", 314

EVENTS

1664 Trinity College, Cambridge awards a scholarship to Isaac Newton to study for his Master's Degree, thus ending his period as a lowly sizar earning his tuition by cleaning up after wealthier students. Within months his formal education would be put on hold as the college closed under the assault of the plague.




1673 Leeuwenhoeck writes his first letter to the Royal Society, which would be published the next month, May 19, in Philosophical Transactions number 94, "A Specimen of Some Observations Made by a Microscope, Contrived by M. Leewenhoeck in Holland, Lately Communicated by Dr. Regnerus de Graaf." Constantijn Huygens, who lived not far from Delft, visited Leeuwenhoek and read the letter. A week before Leeuwenhoek sent it, Huygens sent his own letter to Robert Hooke that acted as a cover letter and recommendation similar to de Graaf's letter in April. Over the rest of Leeuwenhoeck's life, the Society would publish 116 articles containing excerpts from 113 letters. *lensonleeuwenhoek



1686 Newton shows the handwritten copy of his Principia to the Royal Society. *VFR
 28 April 1686 "Dr. Vincent presented a manuscript treatise entitled Philosophiae Naturalis principia mathematica, and dedicated to the Society by Mr. Isaac Newton,..." Minutes of the RS written by Halley clerk to the Society. (It was actually only the manuscript of Book I) *Thony Christie



1693 Leibniz, in a letter to L’Hopital, explains his discovery of determinants. This work was fifty years before that of Cramer who was the real driving force in the development of determinants. Leibniz’s work had no influence because it was not published until 1850 in his Mathematische Schriften. [Smith, Source Book, p. 267] *VFR
Leibniz was convinced that good mathematical notation was the key to progress so he experimented with different notation for coefficient systems. His unpublished manuscripts contain more than 50 different ways of writing coefficient systems which he worked on during a period of 50 years beginning in 1678. Only two publications (1700 and 1710) contain results on coefficient systems and these use the same notation as in his letter to de l'Hôpital mentioned above.
Leibniz used the word 'resultant' for certain combinatorial sums of terms of a determinant. He proved various results on resultants including what is essentially Cramer's rule. He also knew that a determinant could be expanded using any column - what is now called the Laplace expansion. As well as studying coefficient systems of equations which led him to determinants, Leibniz also studied coefficient systems of quadratic forms which led naturally towards matrix theory. In the 1730's Maclaurin wrote Treatise of algebra although it was not published until 1748, two years after his death. It contains the first published results on determinants proving Cramer's rule for 2 X 2 and 3X 3 systems and indicating how the 4 X 4 case would work. Cramer gave the general rule for n X  n systems in his book Introduction to the analysis of algebraic curves (1750). It arose out of a desire to find the equation of a plane curve passing through a number of given points. The rule appears in an Appendix to the book but no proof is given] *SAU (edited and corrected with suggestions by Dave Renfro)
Dave adds:   a 715 page book (xxiii + 680 + xii pages), which is freely available on the internet. Cramer's rule itself appears in Appendix 2 (pp. 657-676). Cramer's book itself was motivated by Newton's work in classifying cubic curves, and I believe he was one of three mathematicians that devoted an extensive study to Newton's classification in the 1700s. (I don't remember who the other two were, but I believe one of them was Euler.) There is an excellent annotated and translation of Newton's work published in 1860 and freely available on the internet:

"Sir Isaac Newton's Enumeration of Lines of the Third Order, Generation of
Curves by Shadows, Organic Description of Curves, and Construction of
Equations by Curves", Translated from the Latin, with notes and examples,
by C.R.M. Talbot, 1860.
http://books.google.com/books?id=6I97byFB3v0C

http://name.umdl.umich.edu/ABQ9451.0001.001
Thanks again to Dave for the corrections.




1817 Gauss wrote the astronomer H. W. M. Olbers, “I am becoming more and more convinced that the necessity of our [Euclidean] geometry cannot be proved, at least not by human intellect nor for the human intellect.” [G. E. Martin, Foundations of Geometry and the Non-Euclidean Plane, p. 306] *VFR



1983 Greece issued a stamp portraying Archimedes and his Hydrostatic Principle








1897 In a letter to Fuchs, Dedekind expressed skepticism of a tale about Gauss attempting to light his pipe with a copy of his DA
Schering in Gottingen in response to a note from Fuchs that he had found materials related to Guass' Disquisitiones Arithmetica in the papers of Dirichlet had described a story that he had shared with Kronecker a decade before,
"The piece of Guass's Disquisitiones Arithmeticiae, which is found among Dirichlet's papers, is probably that portion which, as Dirichlet told me himself, he saved from the hand of Gauss when the latter lit his pipe with his manuscript of the Disquisitiones Arithmeticae on the day of his doctoral jubilee."
Dedekind reasoned, if Guass had saved the paper for fifty years he obviously valued it, and that if the anecdote were true, Dirichlet surely would have shared it with him as well.
*Uta Merzbach, An Early Version of Gauss's Disquisitiones Arithmeticae, Mathematical Perspectives, 1981

1930, the first U.S. motion picture of the 1.5 minute totality of an eclipse of the sun was taken from an airplane flying about 18,000 feet over at Honey Lake, California. The flight was sponsored by the U.S. Naval Observatory, and carried out by Lt. Leslie E. Gehres amd Chief Photographer J.M.F. Haase of the U.S. Navy. An attempt made during an earlier eclipse had been made by the same photographer on 10 Sep 1923, but was unsuccessful due to cloudy conditions. A U.S. Navy dirigible was first used to make a motion film of an eclipse on 24 Jan 1925. The dirigible was about 4,500 feet above a point almost 19 miles east of Monauk Point, New York, which it filmed the 2-min 5-sec eclipse. *TIS
Couldn't find the movie or stills from it, but this beauty taken from a commercial flight is pretty.




1949 The phrase "Big Bang" is created. Shortly after 6:30 am GMT on BBC's The Third Program, Fred Hoyle used the term in describing theories that contrasted with his own "continuous creation" model for the Universe. "...based on a theory that all the matter in the universe was created in one big bang ... ". *Mario Livio, Brilliant Blunders
"Suddenly, an explosive expansion began, ballooning our universe outwards faster than the speed of light. This was a period of cosmic inflation that lasted mere fractions of a second — about 10^-32 of a second, according to physicist Alan Guth’s 1980 theory that changed the way we think about the Big Bang forever." *Space.com  


Big Bang Background Radiation *ESA Planck





2004 At 11:50 AM a paper was submitted electronically to the American Mathematical Monthly which purports to be the shortest journal entry ever, essentially two words," n2 + 2 can". After some correspondence back and forth, (the journal suggested, "a line or two of explanatin might help") the paper was accepted as a "filler" in the January 2005 issue. *wfnmc.org

2012 Mountain View, Ca—January 19, 2012—
The Computer History Museum (CHM), the world’s leading institution exploring the history of computing and its ongoing impact on society, today announced its 2012 Fellow Award honorees: Edward A. Feigenbaum, pioneer of artificial intelligence and expert systems; Steve Furber and Sophie Wilson, chief architects of the ARM processor architecture; and Fernando J. Corbató, pioneer of timesharing and the Multics operating system. The four Fellows will be inducted into the Museum’s Hall of Fellows on Saturday, April 28, 2012, at a formal ceremony where Silicon Valley insiders, technology leaders, and Museum supporters will gather to celebrate the accomplishments of the Fellows and their impact on society. This year’s celebration commemorates the 25th Anniversary of the Fellow Awards and will reunite pioneers from more than two decades. *CHM
Mitchell J Feigenbaum - Niels Bohr Institute 2006.




BIRTHS
1765 Sylvestre François Lacroix (April 28, 1765, Paris – May 24, 1843, Paris) was a French mathematician. He displayed a particular talent for mathematics, calculating the motions of the planets by the age of 14. In 1782 at the age of 17 he became an instructor in mathematics at the École Gardes de Marine in Rochefort, France. He returned to Paris and taught courses in astronomy and mathematics at the Lycée. In 1787 he was the co-winner of that year's Grand Prix of the French Académie des Sciences, but was never awarded the prize. The same year the Lycée was abolished and he again moved to the provinces.
In Besançon he taught course in mathematics, physics, and chemistry at the École d'Artillerie. In 1793 he became examiner of the Artillery Corps, replacing Pierre-Simon Laplace in the post. By 1794 he was aiding his old instructor, Gaspard Monge, in creating material for a course on descriptive geometry. In 1799 he was appointed professor at the École Polytechnique. Lacroix produced most of his texts for the sake of improving his courses. The same year he was voted into the newly formed Institut National des Sciences et des Arts. In 1812 he began teaching at the Collège de France, and was appointed chair of mathematics in 1815.
During his career he produced a number of important textbooks in mathematics. Translations of these books into the English language were used in British universities, and the books remained in circulation for nearly 50 years. In 1812 Babbage set up The Analytical Society for the translation of Differential and Integral Calculus and the book was translated into English in 1816 by George Peacock. *Wik He coined the term “analytic geometry.” *VFR



1773 Robert Woodhouse (28 April 1773 – 23 December 1827) was an English mathematician. He was born at Norwich and educated at Caius College, Cambridge, (BA 1795) of which society he was subsequently a fellow. He was elected a Fellow of the Royal Society in December 1802.
His earliest work, entitled the Principles of Analytical Calculation, was published at Cambridge in 1803. In this he explained the differential notation and strongly pressed the employment of it; but he severely criticized the methods used by continental writers, and their constant assumption of non-evident principles. This was followed in 1809 by a trigonometry (plane and spherical), and in 1810 by a historical treatise on the calculus of variations and isoperimetrical problems. He next produced an astronomy; of which the first book (usually bound in two volumes), on practical and descriptive astronomy, was issued in 1812, and the second book, containing an account of the treatment of physical astronomy by Pierre-Simon Laplace and other continental writers, was issued in 1818.
He became the Lucasian Professor of Mathematics in 1820, and subsequently the Plumian professor in the university. As Plumian Professor he was responsible for installing and adjusting the transit instruments and clocks at the Cambridge Observatory. He held that position until his death in 1827.
On his death in Cambridge he was buried in Caius College Chapel.*Wik He was interested in the “metaphysics of the calculus,” i.e., questions such as the proper theoretical foundations of the calculus, the role of geometric and analytic methods, and the importance of notation. *VFR


1774 Francis Baily (28 April 1774 – 30 August 1844) was an English astronomer. He is most famous for his observations of 'Baily's beads' during an eclipse of the Sun. Bailey was also a major figure in the early history of the Royal Astronomical Society, as one of the founders and president four times.
Baily was born at Newbury in Berkshire in 1774 to Richard Baily. After a tour in the unsettled parts of North America in 1796–1797, his journal of which was edited by Augustus de Morgan in 1856, Baily entered the London Stock Exchange in 1799. The successive publication of Tables for the Purchasing and Renewing of Leases (1802), of The Doctrine of Interest and Annuities (1808), and The Doctrine of Life-Annuities and Assurances (1810), earned him a high reputation as a writer on life-contingencies; he amassed a fortune through diligence and integrity and retired from business in 1825, to devote himself wholly to astronomy.
His observations of "Baily's Beads", during an annular eclipse of the sun on 15 May 1836, at Inch Bonney in Roxburghshire, started the modern series of eclipse expeditions. The phenomenon, which depends upon the irregular shape of the moon's limb, was so vividly described by him as to attract an unprecedented amount of attention to the total eclipse of 8 July 1842, observed by Baily himself at Pavia. *Wik

Postage stamp, Great Britain, 1970, honoring the founding of the Royal Astronomical Society, featuring Francis Baily between William and John Herschel (ianridpath.com)



1831 Peter Guthrie Tait FRSE (28 April 1831 – 4 July 1901) was a Scottish mathematical physicist, best known for the seminal energy physics textbook Treatise on Natural Philosophy, which he co-wrote with Kelvin, and his early investigations into knot theory, which contributed to the eventual formation of topology as a mathematical discipline. His name is known in Graph theory mainly for Tait's conjecture.*Wik (Tait's conjecture states that "Every 3-connected planar cubic graph has a Hamiltonian cycle {along the edges} through all its vertices". His conjecture was proved wrong by counterexample in 1946 by W. T. Tutte. The problem is related to the four color theorem.) He helped develop quaternions, an advanced algebra that gave rise to vector analysis and was instrumental in the development of modern mathematical physics. *TIS
Tait’s work on knots led to a hopeful conjecture that atoms are knotted vortices (of ?) and classifications of knots would correspond to different elements. *Ted Courant
Below is The First Seven Orders of Knottiness"-table compiled by P.G. Tait in 1884 with a big hat-tip to Ben Gross@bhgross144 .




1854 Phoebe Sarah Hertha Ayrton (28 April 1854 – 23 August 1923), was a British engineer, mathematician, physicist, and inventor. Known in adult life as Hertha Ayrton, born Phoebe Sarah Marks, she was awarded the Hughes Medal by the Royal Society for her work on electric arcs and ripples in sand and water.
In 1880, Ayrton passed the Mathematical Tripos, but Cambridge did not grant her an academic degree because, at the time, Cambridge gave only certificates and not full degrees to women. Ayrton passed an external examination at the University of London, which awarded her a Bachelor of Science degree in 1881.
In 1899, she was the first woman ever to read her own paper before the Institution of Electrical Engineers (IEE). Her paper was entitled "The Hissing of the Electric Arc". Shortly thereafter, Ayrton was elected the first female member of the IEE; the next woman to be admitted to the IEE was in 1958. She petitioned to present a paper before the Royal Society but was not allowed because of her sex and "The Mechanism of the Electric Arc" was read by John Perry in her stead in 1901. Ayrton was also the first woman to win a prize from the Society, the Hughes Medal, awarded to her in 1906 in honour of her research on the motion of ripples in sand and water and her work on the electric arc. By the late nineteenth century, Ayrton's work in the field of electrical engineering was recognised more widely, domestically and internationally. At the International Congress of Women held in London in 1899, she presided over the physical science section. Ayrton also spoke at the International Electrical Congress in Paris in 1900. Her success there led the British Association for the Advancement of Science to allow women to serve on general and sectional committees. *Wik



1868 Georgy Fedoseevich Voronoy (also voronoi)(28 April 1868 – 20 November 1908) introduced what are today called Voronoi diagrams or Voronoi tessellations. Today they have wide applications to the analysis of spatially distributed data, so have become important in topics such as geophysics and meteorology. Although known under different names, the notion occurs in condensed matter physics, and in the study of Lie groups. (Two dimensional diagrams of Voronoi type were considered as early at 1644 by René Descartes and were used by Dirichlet (1850) in the investigation of positive quadratic forms. They were also studied by Voronoi (1907), who extended the investigation of Voronoi diagrams to higher dimensions. They find widespread applications in areas such as computer graphics, epidemiology, geophysics, and meteorology. A particularly notable use of a Voronoi diagram was the analysis of the 1854 cholera epidemic in London, in which physician John Snow determined a strong correlation of deaths with proximity to a particular (and infected) water pump on Broad Street. *Mathworld)  Snow mapped the distance to the nearest water pump for each residence in that area of London.
Voronoi diagram using Euclidean distance *Wik




1900 Jan Hendrik Oort (28 April 1900 – 5 November 1992) was a Dutch astronomer who made significant contributions to the understanding of the Milky Way and who was a pioneer in the field of radio astronomy. His New York Times obituary called him “one of the century's foremost explorers of the universe;” the European Space Agency website describes him as, “one of the greatest astronomers of the 20th century,” and states that he “revolutionised astronomy through his ground-breaking discoveries.” In 1955, Oort’s name appeared in Life Magazine’s list of the 100 most famous living people. He has been described as “putting the Netherlands in the forefront of postwar astronomy.”

Oort determined that the Milky Way rotates and overturned the idea that the Sun was at its center. He also postulated the existence of the mysterious invisible dark matter in 1932, which is believed to make up roughly 84.5% of the total matter in the Universe and whose gravitational pull causes “the clustering of stars into galaxies and galaxies into connecting strings of galaxies.” He discovered the galactic halo, a group of stars orbiting the Milky Way but outside the main disk. Additionally Oort is responsible for a number of important insights about comets, including the realization that their orbits “implied there was a lot more solar system than the region occupied by the planets.”

The Oort cloud, the Oort constants, and the Asteroid, 1691 Oort, were all named after him. *Wik




1906 Kurt Godel (April 28, 1906 – January 14, 1978) Austrian-born US mathematician, logician, and author of Gödel's proof. He is best known for his proof of Gödel's Incompleteness Theorems (1931) He proved fundamental results about axiomatic systems showing in any axiomatic mathematical system there are propositions that cannot be proved or disproved within the axioms of the system. In particular the consistency of the axioms cannot be proved. This ended a hundred years of attempts to establish axioms to put the whole of mathematics on an axiomatic basis.*TIS



1906 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




1923 Fritz Joseph Ursell FRS (28 April 1923 – 11 May 2012) was a British mathematician noted for his contributions to fluid mechanics, especially in the area of wave-structure interactions.[5] He held the Beyer Chair of Applied Mathematics at the University of Manchester from 1961–1990, was elected Fellow of the Royal Society in 1972 and retired in 1990.
Ursell came to England as a refugee in 1937 from Germany. From 1941 to 1943 he studied at Trinity College, Cambridge, graduating with a bachelor degree in mathematics. *Wik




1928  Eugene Merle Shoemaker (April 28, 1928 – July 18, 1997)  was an American planetary geologist. Shoemaker initiated and vigorously promoted the intensive geologic training of the astronauts that made them able scientific observers and reporters on moon landings. He was a major investigator of the imaging by unmanned Ranger and Surveyor satellites which, before any Apollo landing, revealed the nature of the Moon's cover of soil and broken rock that he named the regolith. He co-discovered Comet Shoemaker–Levy 9 with his wife Carolyn S. Shoemaker and David H. Levy.  The comet, which collided with Jupiter (1994), was the first observed collision of two solar system bodies. He died in a car crash. In tribute, a small capsule of his ashes were launched in a memorial capsule aboard Lunar Prospector to the moon. *TIS
Comet Shoemaker–Levy 9 (formally designated D/1993 F2) broke apart in July 1992 and collided with Jupiter in July 1994, providing the first direct observation of an extraterrestrial collision of Solar System objects.
Shoemaker–Levy 9, disrupted comet on a collision course
(total of 21 fragments, taken in July 1994)
Gene & Carolyn Shoemaker








DEATHS
1843 William Wallace (23 September 1768, Dysart—28 April 1843, Edinburgh) worked on geometry and discovered the (so-called)
Simson line of a triangle.*SAU In geometry, given a triangle ABC and a point P on its circumcircle, the three closest points to P on lines AB, AC, and BC are collinear. The line through these points is the Simson line of P, named for Robert Simson. The concept was first published, however, by William Wallace.*Wik
 Mary Sommerville was one of his students.  He succeeded John Playfair as Math Chair in Edinburgh. He also invented a complicated type of pantograph called the eidograph.


1903 Josiah Willard Gibbs (February 11, 1839 – April 28, 1903) was an American mathematical physicist and chemist known for contributions to vector analysis and as one of the founders of physical chemistry. In 1863, He was awarded Yale University's first engineering doctorate degree. His major work was in developing thermodynamic theory, which brought physical chemistry from an empirical inquiry to a deductive science. In 1873, he published two papers concerning the fundamental nature of entropy of a system, and established the "thermodynamic surface," a geometrical and graphical method for the analysis of the thermodynamic properties of substances. His famous On the Equilibrium of Homogeneous Substances, published in 1876, established the use of "chemical potential," now an important concept in physical chemistry. *TIS
He is buried at the  Grove Street Cemetery in New Haven Connecticut, USA.

1946 Louis Jean-Baptiste Alphonse Bachelier (March 11, 1870 – April 28, 1946) was a French mathematician at the turn of the 20th century. He is credited with being the first person to model the stochastic process now called Brownian motion, which was part of his PhD thesis The Theory of Speculation, (published 1900).
His thesis, which discussed the use of Brownian motion to evaluate stock options, is historically the first paper to use advanced mathematics in the study of finance. Thus, Bachelier is considered a pioneer in the study of financial mathematics and stochastic processes. *Wik Bachelier is now recognised internationally as the father of financial mathematics, but this fame, which he so justly deserved, was a long time coming. The Bachelier Society, named in his honour, is the world-wide financial mathematics society and mathematical finance is now a scientific discipline of its own. The Society held its first World Congress on 2000 in Paris on the hundredth anniversary of Bachelier's celebrated PhD Thesis, Théorie de la Spéculation *SAU




1986 R H Bing (October 20, 1914, Oakwood, Texas – April 28, 1986, Austin, Texas) He wrote papers on general topology, particularly on metrization; planar sets where he examined in particular planar webs, cuttings and planar embeddings. He worked on topological classification of the 2-sphere, the 3-sphere, pseudo arcs, simple closed curves and Hilbert space. He studied partitions and decompositions of locally connected continua. He considered several different aspects of 3-manifolds including decompositions, maps, approximating surfaces, recognizing tameness, triangulation and the Poincaré conjecture. *SAU Oakwood had a population of 471 at the 2000 census.



1991 Paul Ernest Klopsteg (May 30, 1889 – April 28, 1991) was an American physicist. The asteroid 3520 Klopsteg was named after him and the yearly Klopsteg Memorial Award was founded in his memory.
He performed ballistics research during World War I at the US Army's Aberdeen Proving Grounds in Maryland. He applied his knowledge of ballistics to the study of archery.
He was director of research at Northwestern University Technical Institution. From 1951 through 1958 he was helped organize the National Science Foundation and was an associate director of the National Science Foundation and was president of the American Association for the Advancement of Science from 1958 through 1959.*Wik





1999 Arthur Leonard Schawlow (May 5, 1921 – April 28, 1999) was an American physicist. He is best remembered for his work on lasers, for which he shared the 1981 Nobel Prize in Physics with Nicolaas Bloembergen and Kai Siegbahn.
In 1991 the NEC Corporation and the American Physical Society established a prize: the Arthur L. Schawlow Prize in Laser Science. The prize is awarded annually to "candidates who have made outstanding contributions to basic research using lasers."
In 1951, he married Aurelia Townes, younger sister to physicist Charles Hard Townes, and together they had three children; Arthur Jr., Helen, and Edith. Arthur Jr. was autistic, with very little speech ability.
Schawlow and Professor Robert Hofstadter at Stanford, who also had an autistic child, teamed up to help each other find solutions to the condition. Arthur Jr. was put in a special center for autistic individuals, and later Schawlow put together an institution to care for people with autism in Paradise, California. It was later named the Arthur Schawlow Center in 1999, shortly before his death on the 29th of April 1999.
Schawlow died of leukemia in Palo Alto, California.*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