Mazur's torsion theorem
From Wikipedia, the free encyclopedia
In algebraic geometry Mazur's torsion theorem, due to Barry Mazur, classifies the possible torsion subgroups of the group of rational points on an elliptic curve defined over the rational numbers.
If Cn denotes the cyclic group of order n, then the possible torsion subgroups are Cn with 1 ≤ n ≤ 10, and also C12; and the direct sum of C2 with C2, C4, C6 or C8.
[edit] References
Mazur, Barry: Rational isogenies of prime degree, Inventiones Math. 44 (1978), pp 129-162.
