Birational induction of nilpotent orbit covers in exceptional types

Abstract

Let $G$ be a semisimple simply connected algebraic group over $\mathbb{C}$ of exceptional type. For each $G$-equivariant nilpotent cover of a nilpotent coadjoint $G$-orbit $\mathbb{O}$, we determine the unique birationally rigid induction datum from which it is birationally induced.

arXiv comment61 pages, 10 tables (5 giving main results). v2: New Section 3 added, and parts of Section 4 streamlined accordingly. Other minor errors corrected. v3: Minor errors corrected