Automorphism groups and Homogeneous fibrations on projective varieties with nef anticanonical divisors

Zhan Li; Jinsong Xu

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arXiv · 2609.09976

Automorphism groups and Homogeneous fibrations on projective varieties with nef anticanonical divisors

Zhan Li·Jinsong Xu

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Abstract

We explore the homogeneous structures of Albanese morphisms and maximal rationally chain-connected fibrations of algebraic varieties with nef anticanonical divisors. Furthermore, we show that there exists a natural group homomorphism associated with a maximal rationally chain-connected fibration, which induces the Chevalley decomposition of $\operatorname{Aut}^0$ up to an isogeny. This result is analogous to a similar theorem of Nishi and Matsumura for Albanese morphisms. In addition, we reprove Nishi and Matsumura's theorem using the modern language of algebraic geometry.

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BibTeX RIS

Zhan Li, Jinsong Xu. 2026-09-09. Automorphism groups and Homogeneous fibrations on projective varieties with nef anticanonical divisors. https://arxiv.org/abs/2609.09976

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