Igor Rostislavovich Shafarevich was born on June 3, 1923, and died on February 19, 2017.
He was a Russian mathematician.
Shafarevich contributed to algebraic number theory and algebraic geometry.
Shafarevich wrote books and articles that criticize socialism and was an important dissident during the Soviet regime.
He made fundamental contributions to several parts of mathematics including algebraic number theory, algebraic geometry and arithmetic algebraic geometry.
In his algebraic number theory, called the Shafarevich–Weil theorem extends the commutative reciprocity map to the case of Galois groups which are extensions of abelian groups by finite groups.
He was the first to give a completely self-contained formula for the pairing which coincides with the wild Hilbert symbol on local fields, thus initiating an important branch of the study of explicit formulas in number theory.
His famous result is Shafarevich’s theorem on solvable Galois groups giving the realization of every finite solvable group as the Galois group over rationals.
One more fundamental result is the Golod-Shafarevich theorem on towers of unramified extensions of number fields.
He died in Moscow.
Igor Shafarevich passed away at 93 years old.