Ramification divisors for branched coverings of \({\mathbb{P}}^ n\)
Let X be a log-terminal projective variety of dimension n defined over an algebraically closed field of characteristic zero and \(f: X\to {\mathbb{P}}^ n\) a branched covering. Then it is proved that the ramification divisor R of f is an ample \({\mathbb{Q}}\)-Cartier divisor unless f is an isomorphism. This result generalizes theorem 1 of a paper by \textit{L. Ein} [Math. Ann. 261, 483-485 (1982; Zbl 0519.14005)].
scientific article; zbMATH DE number 4132321