Question: Leonid Kantorovich and Vladimir Arnold both acted as what in the Soviet Union?

Context paragraphs:
Smale's problems: Smale's problems are a list of eighteen unsolved problems in mathematics that was proposed by Steve Smale in 1998, republished in 1999.  Smale composed this list in reply to a request from Vladimir Arnold, then vice-president of the International Mathematical Union, who asked several mathematicians to propose a list of problems for the 21st century.  Arnold's inspiration came from the list of Hilbert's problems that had been published at the beginning of the 20th century.

1974 October Revolution Parade: The 1974 October Revolution Parade was a parade on Red Square dedicated to the 57th anniversary of the October Revolution on November 7th 1974.  It was inspected by the Minister of Defense and Marshal of the Soviet Union Andrei Grechko who also made a speech to the Soviet People on Red Square on the grandstand of Lenin's Mausoleum.  The Parade Commander is the Commander of the Moscow Garrison Colonel General Vladimir Govorov.  Also on Lenin's Mausoleum is the General Secretary of the Communist Party of the Soviet Union Leonid Brezhnev and the President Nikolai Podgorny.  This Parade is the last to feature heavy nuclear missiles such as Ballistic Missiles.  Due to the rain that took place that day the parade of workers and athletes after the parade finale was cancelled.Although the demonstrations on Red Square was Cancelled the demonstrations on Palace Square in Leningrad continued following the parade there.

1975 October Revolution Parade: The 1975 October Revolution Parade was a parade on Red Square dedicated to the 58th anniversary of the October Revolution on November 7th 1975.  Marshal of the Soviet Union Andrei Grechko gave his last speech on the grandstand of Lenin's Mausoleum, before he died the following April.  Commanding the parade was the head of the Moscow Military District Colonel General Vladimir Govorov.  Providing the music for his final parade, was conducted by Major General Nikolai Nazarov of the combined massed bands of the Moscow Garrison.  A scaled down display of military technologies was also present.  General Secretary of the Communist Party of the Soviet Union Leonid Brezhnev and Soviet Prime Minister Alexei Kosygin were present at the parade.

Leonid Kantorovich: Leonid Vitaliyevich Kantorovich (Russian: Леони́д Вита́льевич Канторо́вич ; ] ) (19 January 19127 April 1986) was a Soviet mathematician and economist, known for his theory and development of techniques for the optimal allocation of resources.  He is regarded as the founder of linear programming.  He was the winner of the Stalin Prize in 1949 and the Nobel Memorial Prize in Economics in 1975.

Legacy of Leonid Brezhnev: The full understanding of the history of the late Soviet Union and of its successor, the Russian Federation, requires the assessment of the legacy of Leonid Brezhnev, the third General Secretary of the Central Committee of the Communist Party of the Soviet Union (CPSU) and twice Chairman of the Presidium of the Supreme Soviet.  Leonid Brezhnev was the leader of the CPSU from 1964 until his death in 1982, whose eighteen-year reign was recognised as the time of social and economic stagnation in the late Soviet Union.

List of things named after Vladimir Arnold: A list of things named after Vladimir Arnold, a Russian and Soviet mathematician.

Agriculture in the Soviet Union: Agriculture in the Soviet Union was mostly collectivized, with some limited cultivation of private plots.  It is often viewed as one of the more inefficient sectors of the economy of the Soviet Union.  A number of food taxes (prodrazverstka, prodnalog, and others) were introduced in the early Soviet period despite the Decree on Land that immediately followed the October Revolution.  The forced collectivization and class war against (vaguely defined) "kulaks" under Stalinism greatly disrupted farm output in the 1920s and 1930s, contributing to the Soviet famine of 1932–33 (most especially the holodomor in Ukraine).  A system of state and collective farms, known as sovkhozes and kolkhozes respectively, placed the rural population in a system intended to be unprecedentedly productive and fair but which turned out to be chronically inefficient and lacking in fairness.  Under the administrations of Nikita Khrushchev, Leonid Brezhnev, and Mikhail Gorbachev, a large number of reforms (such as Khrushchev's Virgin Lands Campaign) were enacted as attempts to defray the inefficiencies of the Stalinist agricultural system.  However, Marxist–Leninist ideology did not allow for any substantial amount of market mechanism to coexist alongside central planning, so the private plot fraction of Soviet agriculture, which was its most productive, remained confined to a limited role.  Throughout its later decades the Soviet Union never stopped using substantial portions of the precious metals mined each year in Siberia to pay for grain imports, which has been taken by various authors as an economic indicator showing that the country's agriculture was never as successful as it ought to have been.  The real numbers, however, were treated as state secrets at the time, so accurate analysis of the sector's performance was limited outside the USSR and nearly impossible to assemble within its borders.  However, Soviet citizens as consumers were familiar with the fact that foods, especially meats, were often noticeably scarce, to the point that not lack of money so much as lack of things to buy with it was the limiting factor in their standard of living.

Vladimir Arnold: Vladimir Igorevich Arnold (alternative spelling Arnol'd, Russian: Влади́мир И́горевич Арно́льд , 12 June 1937 – 3 June 2010) was a Soviet and Russian mathematician.  While he is best known for the Kolmogorov–Arnold–Moser theorem regarding the stability of integrable systems, he made important contributions in several areas including dynamical systems theory, catastrophe theory, topology, algebraic geometry, symplectic geometry, differential equations, classical mechanics, hydrodynamics and singularity theory, including posing the ADE classification problem, since his first main result—the solution of Hilbert's thirteenth problem in 1957 at the age of 19.

Leonid Zamyatin: Leonid Mitrofanovich Zamyatin (Russian: Леонид Митрофанович Замятин ) (born 9 March 1922) is a former Soviet ambassador and diplomat.  He graduated from the Moscow Aviation Institute, and worked as a diplomat from 1946.  He became an adviser to the Soviet delegation at the United Nations, and a permanent representative of the Soviet Union on the IAEA Board of Governors.  From 1962 to 1970, he served in the Ministry of Foreign Affairs of the Soviet Union, becoming head of the press department.  From 1970 to 1978, he was director general of TASS, the official news agency of the Soviet Union.  He was Chairman of the International Information Department of the Central Committee of the Communist Party of the Soviet Union from 1978 to 1986.  In 1986, he was appointed the Soviet ambassador to the United Kingdom.  He was forced to resign his ambassadorship after his refusal to condemn the 1991 August Coup against Mikhail Gorbachev.

Leonid Brezhnev: Leonid Ilyich Brezhnev ( ; (19 December 1906-10 November 1982) was a Soviet politician who led the Soviet Union from 1964 to 1982 as the General Secretary of the Central Committee (CC) of the Communist Party of the Soviet Union (CPSU) until his death and funeral in 1982.  His eighteen-year term as General Secretary was second only to that of Joseph Stalin in duration.  During Brezhnev's rule, the global influence of the Soviet Union grew dramatically, in part because of the expansion of the Soviet military during this time.  His tenure as leader was marked by the beginning of an era of economic and social stagnation in the Soviet Union.

Supporting paragraphs: Vladimir Arnold Leonid Kantorovich
Answer: mathematician