Mikhail Ostrogradsky

Mikhail Ostrogradsky
Mikhail Vasilyevich Ostrogradsky
Born	(1801-09-24)September 24, 1801 Pashenivka, (Ukraine, Russian Empire)
Died	January 1, 1862(1862-01-01) (aged 60) Poltava
Citizenship	Russian Empire
Alma mater	University of Kharkiv, University of Paris
Known for	Ostrogradsky instability, Divergence theorem
Scientific career
Fields	Mathematics

Mikhail Vasilyevich Ostrogradsky (transcribed also Ostrohradskyy, Ostrogradskii, Ostrogradskiĭ) (Russian: Михаил Васильевич Остроградский, Ukrainian: Михайло Васильович Остроградський, September 24, 1801 – January 1, 1862) was a Ukrainian mathematician, mechanician and physicist in the Russian Empire. Ostrogradsky is considered to be a disciple of Leonhard Euler and one of the leading mathematicians of Imperial Russia.

Ostrogradsky was born on September 24, 1801 in the village of Pashenivka (at the time in the Poltava Governorate, Russian Empire, today in Poltava Oblast, Ukraine). From 1816 to 1820 he studied under Timofei Osipovsky (1765–1832) and graduated from the University of Kharkiv. When 1820 Osipovsky was suspended on religious grounds, Ostrogradsky refused to be examined and he never received his Doctor's degree. From 1822 to 1826 he studied at the Sorbonne and at the Collège de France in Paris, France. In 1828 he returned to the Russian Empire and settled in Saint Petersburg, where he was elected a member of the Academy of Sciences, Also he became a professor of the Main military engineering School of the Russian Empire.

A 2 hryvna commemorative coin minted by the National Bank of Ukraine in 2001.

Commemorative plaque in Poltava on the last house where Ostrogradsky resided.

He worked mainly in the mathematical fields of calculus of variations, integration of algebraic functions, number theory, algebra, geometry, probability theory and in the fields of applied mathematics, mathematical physics and classical mechanics. In the latter, his most important work includes researches of the motion of an elastic body and the development of methods for integration of the equations of dynamics and fluid power. Here he continued works of Euler, Joseph Louis Lagrange, Siméon Denis Poisson and Augustin Louis Cauchy. In Russia, his work in these fields was continued by Nikolay Dmitrievich Brashman (1796–1866), August Yulevich Davidov (1823–1885) and especially by Nikolai Yegorovich Zhukovsky (1847–1921).

Ostrogradsky's grave in the village of Pashenivka, where he was born.

Ostrogradsky did not appreciate the work on non-Euclidean geometry of Nikolai Lobachevsky from 1823 and he rejected it, when it was submitted for publication in the Saint Petersburg Academy of Sciences.

His method for integrating the rational functions is well known. With his equation we separate integral of a fractional rational function, the sum of the rational part (algebraic fraction) and the transcendental part (with the logarithm and the arctangent). We determine the rational part without integrating it and we assign a given integral into Ostrogradsky's form:

$\int {R(x) \over P(x)}\,dx={T(x) \over S(x)}+\int {X(x) \over Y(x)}\,dx,$

where P(x), S(x), Y(x) are known polynomials of degrees p, s and y, R(x) known polynomial of degree not greater than p − 1, T(x) and X(x) unknown polynomials of degrees not greater than s − 1 and y − 1 respectively.

S(x) is the greatest common divisor of P(x) and P'(x) Denominator of the remaining integral Y(x) can be calculated from equation P(x)=S(x)Y(x)

Ostrogradsky died in Poltava in 1862, aged 60. The Kremenchuk Mykhailo Ostrohradskyi National University in Kremenchuk, Poltava oblast, as well as Ostrogradsky street in Poltava, are named after him.

See also

• Divergence theorem (Ostrogradsky–Gauss theorem / Gauss–Ostrogradsky // Green–Ostrogradsky–Gauss / Gauss–Green–Ostrogradsky)
• Ostrogradsky's equation
  • $\iiint _{V}\left({\partial P \over \partial x}+{\partial Q \over \partial y}+{\partial R \over \partial z}\right)dx\,dy\,dz=\iint _{\Sigma }\left(P+Q+R\right)\,d\Sigma$
• Green's theorem (1827)
• Green–Ostrogradsky equation (1828)
• Hamilton–Ostrogradsky (variational) principle
• Ostrogradsky formalism
• Einstein–Ostrogradsky–Dirac Hamiltonian
• Horowitz–Ostrogradsky method
• Jacobi–Ostrogradsky coordinates
• Ostrogradsky instability

External links

• O'Connor, John J.; Robertson, Edmund F., "Mikhail Ostrogradsky", MacTutor History of Mathematics Archive, University of St Andrews
• Woodard, R.P. (9 Aug 2015). "The Theorem of Ostrogradsky". arXiv:1506.02210.