Finiteness of projective pluricanonical representation for automorphisms of complex manifolds

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Loginov, Konstantin, Shramov, Constantin
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866916681077489664
author Loginov, Konstantin
Shramov, Constantin
author_facet Loginov, Konstantin
Shramov, Constantin
contents We study the action of the group of bimeromorphic automorphisms $\mathrm{Bim}(X)$ of a compact complex manifold $X$ on the image of the pluricanonical map, which we call the projective pluricanonical representation of this group. If $X$ is a Moishezon variety, then the image of $\mathrm{Bim}(X)$ via such a representation is a finite group by a classical result due to Deligne and Ueno. We prove that this image is a finite group under the assumption that for the Kodaira dimension $κ(X)$ of $X$ we have $κ(X)=\dim X-1$. To this aim, we prove a version of the canonical bundle formula in relative dimension $1$ which works for a proper morphism from a complex variety to a projective variety. In particular, this establishes the analytic version of Prokhorov--Shokurov conjecture in relative dimension $1$. Also, we observe that the analytic version of this conjecture does not hold in relative dimension $2$.
format Preprint
id arxiv_https___arxiv_org_abs_2504_06654
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Finiteness of projective pluricanonical representation for automorphisms of complex manifolds
Loginov, Konstantin
Shramov, Constantin
Algebraic Geometry
We study the action of the group of bimeromorphic automorphisms $\mathrm{Bim}(X)$ of a compact complex manifold $X$ on the image of the pluricanonical map, which we call the projective pluricanonical representation of this group. If $X$ is a Moishezon variety, then the image of $\mathrm{Bim}(X)$ via such a representation is a finite group by a classical result due to Deligne and Ueno. We prove that this image is a finite group under the assumption that for the Kodaira dimension $κ(X)$ of $X$ we have $κ(X)=\dim X-1$. To this aim, we prove a version of the canonical bundle formula in relative dimension $1$ which works for a proper morphism from a complex variety to a projective variety. In particular, this establishes the analytic version of Prokhorov--Shokurov conjecture in relative dimension $1$. Also, we observe that the analytic version of this conjecture does not hold in relative dimension $2$.
title Finiteness of projective pluricanonical representation for automorphisms of complex manifolds
topic Algebraic Geometry
url https://arxiv.org/abs/2504.06654