用户: Fyx1123581347/椭圆曲线主齐性空间的计算

设 $E/K$ 为椭圆曲线, $K(\sqrt{d})/K$ 为二次扩张. 设 $T\in E(K)$ 为非平凡的二阶点, 则同态$$\begin{array}{r}\xi :G_{\bar{K}/K}⟶E,\\ \sigma \to \{\begin{array}{ll}O& \text{if}\end{array}\end{array}$$