Pontryagin's maximum (or minimum) principle is used in optimal control theory to find the best possible control for taking a dynamical system from one state to another, especially in the presence of constraints for the state or input controls.
 It was formulated in 1956 by the Russian mathematician Lev Pontryagin and his students.
 It has as a special case the Euler–Lagrange equation of the calculus of variations.
The Hamiltonian of optimal control theory was developed by Lev Pontryagin as part of his maximum principle.
 It was inspired by, but is distinct from, the Hamiltonian of classical mechanics.
 Pontryagin proved that a necessary condition for solving the optimal control problem is that the control should be chosen so as to minimize the Hamiltonian.
 For details see Pontryagin's maximum principle.
In mathematics, the Pontryagin classes, named for Lev Pontryagin, are certain characteristic classes.
 The Pontryagin class lies in cohomology groups with degree a multiple of four.
 It applies to real vector bundles.
Lev Semyonovich Pontryagin (Russian: Лев Семёнович Понтрягин , also written Pontriagin or Pontrjagin) (3 September 1908 – 3 May 1988) was a Soviet mathematician.
 He was born in Moscow and lost his eyesight due to a primus stove explosion when he was 14.
 Despite his blindness he was able to become one of the greatest mathematicians of the 20th century, partially with the help of his mother Tatyana Andreevna who read mathematical books and papers (notably those of Heinz Hopf, J. H. C. Whitehead, and Hassler Whitney) to him.
 He made major discoveries in a number of fields of mathematics, including algebraic topology and differential topology.
Vladimir Iosifovich Levenshtein (Russian: Влади́мир Ио́сифович Левенште́йн ; ] ; born 1935) is a Russian scientist who has done research in information theory, error-correcting codes, and combinatorial design.
 Among other contributions, he is known for the Levenshtein distance and a Levenshtein algorithm, which he developed in 1965.
In information theory, Linguistics and computer science, the Levenshtein distance is a string metric for measuring the difference between two sequences.
 Informally, the Levenshtein distance between two words is the minimum number of single-character edits (insertions, deletions or substitutions) required to change one word into the other.
 It is named after Vladimir Levenshtein, who considered this distance in 1965.
Levenstein coding, or Levenshtein coding, is a universal code encoding the non-negative integers developed by Vladimir Levenshtein.
In mathematics, Tannaka–Krein duality theory concerns the interaction of a compact topological group and its category of linear representations.
 It is a natural extension of Pontryagin duality, between compact and discrete commutative topological groups, to groups that are compact but noncommutative.
 The theory is named for two men, the Soviet mathematician Mark Grigorievich Krein, and the Japanese Tadao Tannaka.
 In contrast to the case of commutative groups considered by Lev Pontryagin, the notion dual to a noncommutative compact group is not a group, but a category Π("G") with some additional structures, formed by the finite-dimensional representations of "G".
The Andronov–Pontryagin criterion is a necessary and sufficient condition for the stability of dynamical systems in the plane.
 It was derived by Aleksandr Andronov and Lev Pontryagin in 1937.
In mathematics, the Thom space, Thom complex, or Pontryagin–Thom construction (named after René Thom and Lev Pontryagin) of algebraic topology and differential topology is a topological space associated to a vector bundle, over any paracompact space.

Question: Who was born first, Lev Pontryagin or Vladimir Levenshtein?
Answer: Lev Semyonovich Pontryagin