11 problems.
Curves and Rationality
- \(\PP^n\cross \PP^m\) is a rational variety
- Maps of finite degree between genus one curves are unramified
- Every genus zero smooth projective curve over \(\CC\) is a plane conic
- \(\OO_Y \to \pi_* \OO_X\) is an isomorphism exactly when \(Y\) is integrally closed in \(K(X)\)
- A family of genus-zero curves over a curve is a \(\PP^1\)-bundle