English

Semi-group structure of all endomorphisms of a projective variety admitting a polarized endomorphism

Algebraic Geometry 2020-06-11 v2 Dynamical Systems

Abstract

Let XX be a projective variety admitting a polarized (or more generally, int-amplified) endomorphism. We show: there are only finitely many contractible extremal rays; and when XX is Q\mathbb{Q}-factorial normal, every minimal model program is equivariant relative to the monoid SEnd(X)SEnd(X) of all surjective endomorphisms, up to finite index. Further, when XX is rationally connected and smooth, we show: there is a finite-index submonoid GG of SEnd(X)SEnd(X) such that GG acts via pullback as diagonal (and hence commutative) matrices on the Neron-Severi group; the full automorphisms group Aut(X)Aut(X) has finitely many connected components; and every amplified endomorphism is int-amplified.

Keywords

Cite

@article{arxiv.1806.05828,
  title  = {Semi-group structure of all endomorphisms of a projective variety admitting a polarized endomorphism},
  author = {Sheng Meng and De-Qi Zhang},
  journal= {arXiv preprint arXiv:1806.05828},
  year   = {2020}
}

Comments

Mathematical Research Letters (to appear); minor changes