Pafnuty Chebyshev

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Pafnuty Chebyshev
Chebyshev.jpg
Pafnuty Lvovich Chebyshev
Born(1821-05-16)16 May 1821
Died8 December 1894(1894-12-08) (aged 73)
Nationality Russian
Other namesChebysheff, Chebyshov, Tschebyscheff, Tschebycheff
Alma mater Moscow University
Known forWork on probability, statistics, mechanics, analytical geometry and number theory
Awards Demidov Prize (1849)
Scientific career
Fields Mathematician
Institutions St. Petersburg University
Academic advisors Nikolai Brashman
Notable students Dmitry Grave
Aleksandr Korkin
Aleksandr Lyapunov
Andrey Markov
Vladimir Andreevich Markov
Konstantin Posse

Pafnuty Lvovich Chebyshev (Russian :Пафну́тий Льво́вич Чебышёв,IPA:  [pɐfˈnutʲɪj ˈlʲvovʲɪtɕ tɕɪbɨˈʂof] ) (16 May [ O.S. 4 May] 18218 December [ O.S. 26 November] 1894) [1] was a Russian mathematician. His name can be alternatively transliterated as Chebysheff, Chebychov, Chebyshov; or Tchebychev, Tchebycheff (French transcriptions); or Tschebyschev, Tschebyschef, Tschebyscheff (German transcriptions). Chebychev, mixture between English and French transliterations, is sometimes erroneously used.

Russian language East Slavic language

Russian is an East Slavic language, which is official in the Russian Federation, Belarus, Kazakhstan and Kyrgyzstan, as well as being widely used throughout Eastern Europe, the Baltic states, the Caucasus and Central Asia. It was the de facto language of the Soviet Union until its dissolution on 25 December 1991. Although nearly three decades have passed since the breakup of the Soviet Union, Russian is used in official capacity or in public life in all the post-Soviet nation-states, as well as in Israel and Mongolia.

Old Style and New Style dates 16th-century changes in calendar conventions

Old Style (O.S.) and New Style (N.S.) are terms sometimes used with dates to indicate that the calendar convention used at the time described is different from that in use at the time the document was being written. There were two calendar changes in Great Britain and its colonies, which may sometimes complicate matters: the first was to change the start of the year from Lady Day to 1 January; the second was to discard the Julian calendar in favour of the Gregorian calendar. Closely related is the custom of dual dating, where writers gave two consecutive years to reflect differences in the starting date of the year, or to include both the Julian and Gregorian dates.

Russians are a nation and an East Slavic ethnic group native to European Russia in Eastern Europe. Outside Russia, notable minorities exist in other former Soviet states such as Belarus, Kazakhstan, Moldova, Ukraine and the Baltic states. A large Russian diaspora also exists all over the world, with notable numbers in the United States, Germany, Brazil, and Canada.

Contents

Biography

Early years

One of nine children, [2] Chebyshev was born in the village of Okatovo in the district of Borovsk, province of Kaluga, into a family which traced its roots back to a 17th-century Tatar military leader named Khan Chabysh. [3] His father, Lev Pavlovich, was a Russian nobleman and wealthy landowner. Pafnuty Lvovich was first educated at home by his mother Agrafena Ivanovna (in reading and writing) and by his cousin Avdotya Kvintillianovna Sukhareva (in French and arithmetic). Chebyshev mentioned that his music teacher also played an important role in his education, for she “raised his mind to exactness and analysis.”

Borovsk Town in Kaluga Oblast, Russia

Borovsk is a town and the administrative center of Borovsky District of Kaluga Oblast, Russia, located on the Protva River just south from the oblast's border with Moscow Oblast. Population: 12,283 (2010 Census); 11,917 (2002 Census); 13,405 (1989 Census); 12,000 (1969).

Trendelenburg's gait affected Chebyshev's adolescence and development. From childhood, he limped and walked with a stick and so his parents abandoned the idea of his becoming an officer in the family tradition. His disability prevented his playing many children's games and he devoted himself instead to mathematics.

The Trendelenburg gait is an abnormal gait caused by weakness of the abductor muscles of the lower limb, gluteus medius and gluteus minimus. People with a lesion of superior gluteal nerve have weakness of abducting the thigh at the hip.

In 1832, the family moved to Moscow, mainly to attend to the education of their eldest sons (Pafnuty and Pavel, who would become lawyers). Education continued at home and his parents engaged teachers of excellent reputation, including (for mathematics and physics) P.N. Pogorelski, held to be one of the best teachers in Moscow and who had taught (for example) the writer Ivan Sergeevich Turgenev.

Moscow Capital city of Russia

Moscow is the capital and most populous city of Russia, with 13.2 million residents within the city limits, 17 million within the urban area and 20 million within the metropolitan area. Moscow is one of Russia's federal cities.

Ivan Turgenev 19th-century Russian writer

Ivan Sergeyevich Turgenev was a Russian novelist, short story writer, poet, playwright, translator and popularizer of Russian literature in the West.

University studies

In summer 1837, Chebyshev passed the registration examinations and, in September of that year, began his mathematical studies at the second philosophical department of Moscow University. His teachers included N.D. Brashman, N.E. Zernov and D.M. Perevoshchikov of whom it seems clear that Brashman had the greatest influence on Chebyshev. Brashman instructed him in practical mechanics and probably showed him the work of French engineer J.V. Poncelet. In 1841 Chebyshev was awarded the silver medal for his work “calculation of the roots of equations” which he had finished in 1838. In this, Chebyshev derived an approximating algorithm for the solution of algebraic equations of nth degree based on Newton's method. In the same year, he finished his studies as "most outstanding candidate".

Nikolai Brashman Russian mathematician

Nikolai Dmitrievich Brashman was a Russian mathematician of Jewish-Austrian origin. He was a student of Joseph Johann Littrow, and the advisor of Pafnuty Chebyshev and August Davidov.

Jean-Victor Poncelet French engineer and mathematician

Jean-Victor Poncelet was a French engineer and mathematician who served most notably as the Commanding General of the École Polytechnique. He is considered a reviver of projective geometry, and his work Traité des propriétés projectives des figures is considered the first definitive text on the subject since Gérard Desargues' work on it in the 17th century. He later wrote an introduction to it: Applications d’analyse et de géométrie.

In numerical analysis, Newton's method, also known as the Newton–Raphson method, named after Isaac Newton and Joseph Raphson, is a root-finding algorithm which produces successively better approximations to the roots of a real-valued function.

In 1841, Chebyshev’s financial situation changed drastically. There was famine in Russia, and his parents were forced to leave Moscow. Although they could no longer support their son, he decided to continue his mathematical studies and prepared for the master examinations, which lasted six months. Chebyshev passed the final examination in October 1843 and, in 1846, defended his master thesis “An Essay on the Elementary Analysis of the Theory of Probability.” His biographer Prudnikov suggests that Chebyshev was directed to this subject after learning of recently published books on probability theory or on the revenue of the Russian insurance industry.

Adult years

In 1847, Chebyshev promoted his thesis pro venia legendi “On integration with the help of logarithms” at St Petersburg University and thus obtained the right to teach there as a lecturer. At that time some of Leonhard Euler’s works were rediscovered by P. N. Fuss and were being edited by V. Ya. Bunyakovsky, who encouraged Chebyshev to study them. This would come to influence Chebyshev's work. In 1848, he submitted his work The Theory of Congruences for a doctorate, which he defended in May 1849. He was elected an extraordinary professor at St Petersburg University in 1850, ordinary professor in 1860 and, after 25 years of lectureship, he became merited professor in 1872. In 1882 he left the university and devoted his life to research.

Leonhard Euler Swiss mathematician

Leonhard Euler was a Swiss mathematician, physicist, astronomer, logician and engineer who made important and influential discoveries in many branches of mathematics, such as infinitesimal calculus and graph theory, while also making pioneering contributions to several branches such as topology and analytic number theory. He also introduced much of the modern mathematical terminology and notation, particularly for mathematical analysis, such as the notion of a mathematical function. He is also known for his work in mechanics, fluid dynamics, optics, astronomy and music theory.

Viktor Bunyakovsky Russian mathematician

Viktor Yakovlevich Bunyakovsky was a Russian mathematician, member and later vice president of the Petersburg Academy of Sciences.

Professor academic rank at universities and other post-secondary education and research institutions in most countries

Professor is an academic rank at universities and other post-secondary education and research institutions in most countries. Literally, professor derives from Latin as a "person who professes" being usually an expert in arts or sciences, a teacher of the highest rank.

During his lectureship at the university (1852–1858), Chebyshev also taught practical mechanics at the Alexander Lyceum in Tsarskoe Selo (now Pushkin), a southern suburb of St Petersburg.

His scientific achievements were the reason for his election as junior academician (adjunkt) in 1856. Later, he became an extraordinary (1856) and in 1858 an ordinary member of the Imperial Academy of Sciences. In the same year he became an honorary member of Moscow University. He accepted other honorary appointments and was decorated several times. In 1856, Chebyshev became a member of the scientific committee of the ministry of national education. In 1859, he became an ordinary member of the ordnance department of the academy with the adoption of the headship of the commission for mathematical questions according to ordnance and experiments related to ballistics. The Paris academy elected him corresponding member in 1860 and full foreign member in 1874. In 1893, he was elected honorable member of the St. Petersburg Mathematical Society, which had been founded three years earlier.

Chebyshev died in St Petersburg on 26 November 1894.

Mathematical contributions

Chebyshev is known for his work in the fields of probability, statistics, mechanics, and number theory. The Chebyshev inequality states that if is a random variable with standard deviation σ > 0, then the probability that the outcome of is no less than away from its mean is no more than :

The Chebyshev inequality is used to prove the weak law of large numbers.

The Bertrand–Chebyshev theorem (1845,1852) states that for any , there exists a prime number such that . This is a consequence of the Chebyshev inequalities for the number of prime numbers less than , which state that is of the order of . A more precise form is given by the celebrated prime number theorem: the quotient of the two expressions approaches 1.0 as tends to infinity.

Chebyshev is also known for the Chebyshev polynomials and the Chebyshev bias – the difference between the number of primes that are congruent to 3 (modulo 4) and 1 (modulo 4).

Legacy

Stamp of USSR 1047.jpg

Chebyshev is considered to be a founding father of Russian mathematics. Among his well-known students were the mathematicians Dmitry Grave, Aleksandr Korkin, Aleksandr Lyapunov, and Andrei Markov. According to the Mathematics Genealogy Project, Chebyshev has 12,422 mathematical "descendants" as of July 2018. [4]

The lunar crater Chebyshev and the asteroid 2010 Chebyshev were named to honor his major achievements in the mathematical realm. [5]

Publications

See also

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References

  1. Pafnuty Lvovich Chebyshev – Britannica Online Encyclopedia
  2. Biography in MacTutor Archive
  3. Paul Butzer & François Jongmans, P. L. Chebyshev (1821-1894) : A Guide to his Life and Work, Journal of Approximation Theory, vol. 96, p. 112 (1999)
  4. Pafnuty Chebyshev at the Mathematics Genealogy Project
  5. Schmadel, Lutz D. (2007). "(2010) Chebyshev". Dictionary of Minor Planet Names – (2010) Chebyshev. Springer Berlin Heidelberg. p. 163. doi:10.1007/978-3-540-29925-7_2011. ISBN   978-3-540-00238-3.