Andrey Tikhonov (mathematician)

{{Infobox scientist

| name = Andrey Tikhonov

| image = Tychonoff.jpg

| image_size = 200px

| caption = Tikhonov in 1975

| birth_date = {{Birth date|1906|10|17|df=y}}

| birth_place = Gzhatsk, Russian Empire

| death_date = {{death date and age|1993|10|7|1906|10|30|df=y}}

| death_place = Moscow, Russia

| field = Mathematics

| work_institution = Moscow State University

| alma_mater = Moscow State University

| doctoral_advisor = Pavel Alexandrov

| doctoral_students = Aleksandr Andreyevich Samarskiĭ
Alexei Georgievich Sveshnikov

| known_for = Important contributions to topology, functional analysis, mathematical physics, ill-posed problems;

| prizes =

| footnotes =

}}

Andrey Nikolayevich Tikhonov ({{langx|ru|Андре́й Никола́евич Ти́хонов}}; 17 October 1906 – 7 October 1993) was a leading Soviet Russian mathematician and geophysicist known for important contributions to topology, functional analysis, mathematical physics, and ill-posed problems. He was also one of the inventors of the magnetotellurics method in geophysics. Other transliterations of his surname include "Tychonoff", "Tychonov", "Tihonov", "Tichonov".

Biography

Born in Gzhatsk, he studied at the Moscow State University where he received a Ph.D. in 1927 under the direction of Pavel Sergeevich Alexandrov.{{MathGenealogy|id=58042|name=Andrei Nikolaevich Tikhonov}} In 1933 he was appointed as a professor at Moscow State University. He became a corresponding member of the USSR Academy of Sciences on 29 January 1939 and a full member of the USSR Academy of Sciences on 1 July 1966.

Research work

Tikhonov worked in a number of different fields in mathematics. He made important contributions to topology, functional analysis, mathematical physics, and certain classes of ill-posed problems. Tikhonov regularization, one of the most widely used methods to solve ill-posed inverse problems, is named in his honor. He is best known for his work on topology, including the metrization theorem he proved in 1926, and the Tychonoff's theorem, which states that every product of arbitrarily many compact topological spaces is again compact. In his honor, completely regular topological spaces are also named Tychonoff spaces.

In mathematical physics, he proved the fundamental uniqueness theorems for the heat equation{{cite journal|author=A. Tychonoff|title=Théorèmes d'unicité pour l'équation de la chaleur|journal=Matematicheskii Sbornik|volume=42 | issue = 2 |pages=199–216|year=1935|url= http://mi.mathnet.ru/eng/msb6410}} and studied Volterra integral equations.

He founded the theory of asymptotic analysis for differential equations with small parameter in the leading derivative.{{cite journal |author=A. N. Tikhonov |title=Systems of Differential Equations Containing Small Parameters in the Derivatives |journal=Mathematical Sbornik |volume=31 |issue=73 |page=3 |year=1952 |url=http://mi.mathnet.ru/eng/msb5548}}

Organizer work

Tikhonov played the leading role in founding the Faculty of Computational Mathematics and Cybernetics of Moscow State University and served as its first dean during the period of 1970–1990.

File:Tikhonov board.jpg

Awards

Tikhonov received numerous honors and awards for his work, including the Lenin Prize (1966) and the Hero of Socialist Labor (1954, 1986).

Publications

=Books=

{{cite book |first1=A. G. |last1=Sveshnikov |first2=A. N. |last2=Tikhonov |title=The Theory of Functions of a Complex Variable |publisher=Mir |year=1978}} (English translation.)
{{cite book |first1=A. N. |last1=Tikhonov |first2=V. Y. |last2=Arsenin |title=Solutions of Ill-Posed Problems |publisher=Winston |location=New York |year=1977 |isbn=0-470-99124-0}}{{cite journal|last1=Levine|first1=Howard A.|title=Book Review: Solutions of ill posed problems|journal=Bulletin of the American Mathematical Society|volume=1|issue=3|year=1979|pages=521–525|issn=0273-0979|doi=10.1090/S0273-0979-1979-14602-0|doi-access=free}}
{{cite book |first1=A. N. |last1=Tikhonov |first2=A. V. |last2=Goncharsky |title=Ill-posed Problems in the Natural Sciences |publisher=Oxford University Press |location=Oxford |year=1987 |isbn=0-8285-3739-9}}
{{cite book

}}

{{cite book |first1=A. N. |last1=Tikhonov |first2=A. V. |last2=Goncharsky |first3=V. V. |last3=Stepanov |first4=A. G. |last4=Yagola |title=Numerical Methods for the Solution of Ill-Posed Problems |publisher=Kluwer |location=Dordrecht |year=1995 |isbn=0-7923-3583-X}}
{{cite book |first1=A. N. |last1=Tikhonov |first2=A. S. |last2=Leonov |first3=A. G. |last3=Yagola |title=Nonlinear Ill-Posed Problems |publisher=Chapman and Hall |location=London, Weinheim, New York, Tokyo, Melbourne, Madras |volume=1–2 |year=1998 |isbn=0-412-78660-5}}

=Papers=

{{cite journal|doi=10.1016/0041-5553(62)90005-8|title=Homogeneous difference schemes|year=1962|last1=Tikhonov|first1=A. N.|last2=Samarskii|first2=A. A.|journal=USSR Computational Mathematics and Mathematical Physics|volume=1|pages=5–67|citeseerx=10.1.1.714.1396}}
{{cite journal |last1=Tikhonov |first1=A. N. |last2=Samarskii |first2=A. A. |year=1963 |title=Homogeneous difference schemes on non-uniform nets |journal=USSR Computational Mathematics and Mathematical Physics |volume=2 |issue=5 |pages=927–953 |doi=10.1016/0041-5553(63)90505-6 |url=http://www.samarskii.ru/articles/1963/1963_016.pdf}}
{{cite journal |doi=10.1016/0041-5553(66)90003-6 |title=On the stability of the functional optimization problem|year=1966 |last1=Tikhonov |first1=A. N. |journal=USSR Computational Mathematics and Mathematical Physics |volume=6 |issue=4 |pages=28–33}}