De-Qi Zhang

collaborators

5 papers

math.AG2026

Galois self-covers of projective spaces and essential dimensions

Yujie Luo, De-Qi Zhang

We give the structure theorem of Galois self-covers $f : P^{n} \to P^{n}$ . As an application, we show that the essential dimension of every such nontrivial cover attai…

math.AG2026

Essential dimensions of polarized endomorphisms of certain algebraic surfaces

Qianli Fang, Yujie Luo, De-Qi Zhang

Let $f : X \to X$ be a polarized endomorphism of a smooth projective surface which is birationally ruled. We answer a question of KollÃ¡r and Zhuang, in the affirmative, on the inco…

math.AG2025

Essential dimensions of polarized endomorphisms of abelian varieties

Yujie Luo, Keiji Oguiso, De-Qi Zhang

Let $f$ be a polarized endomorphism of an abelian variety $A$ . KollÃ¡r and Zhuang asked whether the essential dimension $ed (f)$ equals $dim (A)$ . We provide counte…

math.AG2025

Log Calabi-Yau structure of algebaic varieties admitting a polarized endomorphism

Wentao Chang, De-Qi Zhang

Let $X$ be a normal projective variety admitting a polarized endomorphism $f$ , i.e., $f^{*} H \sim q H$ for some ample divisor $H$ and integer $q > 1$ . Then Broustet and Gongyo proposed t…

math.AG2025

On the virtual invariants of zero entropy groups of compact KÃ¤hler manifolds

Tien-Cuong Dinh, Hsueh-Yung Lin, Keiji Oguiso +1

Let $X$ be a compact KÃ¤hler manifold. We study subgroups $G \leq Aut (X)$ of biholomorphic automorphisms of zero entropy when $Aut^{0} (X)$ is compact (e.g. when $\ma…