Complex sentence: In mathematics, an Euler system is collection of compatible elements of Galois cohomology groups indexed by fields, introduced by in his work on Heegner points on modular elliptic curves, who was partly motivated by the work of.
Split into simpler sentences: In mathematics, an Euler system is collection of compatible elements of Galois cohomology groups indexed by fields. They were introduced by in his work on Heegner points on modular elliptic curves, who was partly motivated by the work of.