Higher direct images of dualizing sheaves III
János Kollár, Sándor J. Kovács
Published: 2025/8/22
Abstract
We show that for flat morphisms between varieties with rational singularities, the higher direct images of the structure sheaf are locally free. As a consequence, the identity component of the relative Picard scheme is a smooth algebraic group scheme. v.2. Bhatt pointed out that Lemma 9 was incorrect; it is now replaced. The main theorem is unchanged.