Alexander Kronrod

Aleksandr Semyonovich Kronrod (Алекса́ндр Семёнович Кронро́д; October 22, 1921 – October 6, 1986) was a Soviet mathematician and computer scientist, best known for the Gauss–Kronrod quadrature formula which he published in 1964.

Earlier, he worked on computational solutions of problems emerging in theoretical physics.

He is also known for his contributions to economics, specifically for proposing corrections and calculating price formation for the USSR.

Later, Kronrod gave his fortune and life to medicine to care for terminal cancer patients.

Kronrod is remembered for his captivating personality and was admired as a student, teacher and leader.

He is the author of several well known books, including "Nodes and weights of quadrature formulas. Sixteen-place tables" and "Conversations on Programming".

A biographer wrote Kronrod gave ideas "away left and right, quite honestly being convinced that the authorship belongs to the one who implements them."

Kronrod was born in Moscow.

Growing up, he studied math with D. O. Shklyarsky in school and in 1938 entered the Department of Mechanics and Mathematics at Moscow State University.

He did his first independent mathematical work as a freshman with Professor Alexander Gelfond.

Kronrod was honored as a student with the first prize of the Moscow Mathematical Society and was the only person to win the prize twice.

During World War II he was rejected for military service because at the time graduate level students were exempt.

They did help to build trenches around Moscow, and when he returned, Kronrod reapplied and was accepted.

He served twice, and was injured twice.

He was awarded several medals, including Order of the Red Star.

The second injury in 1943 hospitalised him for a year and he was discharged from the army in 1944.

This injury made him an invalid of sorts for life.

Kronrod was married and about this time his son was born.

During next four years he continued his studies at the University, simultaneously working at the Atomic Energy Kurchatov Institute.

There he chose to leave pure mathematics and pursue computational mathematics.

In his last undergraduate year, Kronrod studied with Nikolai Luzin the teacher of many of the Soviet Union's finest scientists.

Kronrod and Georgy Adelson-Velsky were colleagues and Luzin's last students.

Like his teacher, Kronrod led a series of supplementary seminars for younger mathematics students.

Unusually for the time, instead of students merely reporting on the content of courses, Kronrod made his students undertake training exercises, even proving basic theorems themselves.

The preparation required for this reduced the numbers of participants, but those who remained, including Robert Minlos and Anatoli Vitushkin, derived great benefit.

Vitushkin described him as "witty and friendly".

At his own request, Kronrod was called simply "Sasha" by his students.

He was considered to be a prophet in his field.

The Kronod circle met between 1946 and 1953.

Kronrod's position was formally at the Institute of Physics, which meant that his students had to register with other advisers, accounting for the decline of the circle into a series of friendly meetings.

When he defended thesis in 1949, his committee including Mstislav Keldysh, Andrey Kolmogorov and Dmitrii Menshov bypassed the Candidate of Sciences degree and awarded him a Doctor of Sciences degree in the physical-mathematical sciences.

Kronrod taught at the Moscow Pedagogical Institute.

Evgenii Landis was a student, early collaborator and one of his biographers.

At the Moscow Institute for Theoretical and Experimental Physics (ITEF or ITEP) during 1950–1955 Kronod collaborated with physicists, among them Isaak Pomeranchuk and Lev Landau.

For providing theoretical physics with numerical solutions he received the Stalin Prize and an Order of the Red Banner of Labour.

In 1955, he first used an electronic computer at the Krzhizhanovsky laboratory of the Institute of Energy of the Academy of Sciences of the Soviet Union, later called the Institute for Electronic Control Machines.

He directed the mathematics division of ITEP.

They could surpass the results achieved outside the USSR by far faster machines, in the case of CERN in Geneva, five hundred times faster.

During the 1960s he worked on mathematics education in high schools by organizing courses and teaching methods.

Kronod played an important role in building the first major Russian computer, Relay Computer RVM-1, though he liked to say his colleague N.I. Bessonov was the sole inventor.