The uniform boundedness conjecture for rational torsion of elliptic curves

Let $K$ be a number field and let $E$ be an elliptic curve over $K$. Uniform boundedness conjecture. The order of the rational torsion subgroup $E(K)_\mathrm{tor}$ is bounded by a constant depending only on the degree $[K:\mathbb{Q}]$. This extends Ogg's explicit classification over $\mathbb{Q}$ to all number fields without specifying the bound. The conjecture was proved by Merel.