THE NOETHER INEQUALITY FOR ALGEBRAIC 3-FOLDS

摘要

We establish the Noether inequality for projective 3-folds, and, specifically, we prove that the inequality holds for all projective 3-folds X of general type with either pg(X) 4 or pg(X) ≤ 21, where pg.(X) is the geometric genus and vol.(X) is the canonical volume. This inequality is optimal due to known examples found by Kobayashi in 1992.