English

A finiteness result on representations of Nori's fundamental group scheme

Algebraic Geometry 2026-04-23 v2

Abstract

Let (X,x)(X,x) be a pointed geometrically connected smooth projective variety over a sub-pp-adic field KK. For any given rank nn, we prove that there are only finitely many isomorphism classes of representations π1EF(X,x)GLn\pi_{1}^{EF}(X,x)\rightarrow \mathrm{GL}_{n}, where π1EF(X,x)\pi_{1}^{EF}(X,x) is Nori's fundamental group of essentially finite bundles. Equivalently, there are only finitely many isomorphism classes of essentially finite bundles of rank nn. This answers a question from C.Gasbarri.

Keywords

Cite

@article{arxiv.2601.13917,
  title  = {A finiteness result on representations of Nori's fundamental group scheme},
  author = {Xiaodong Yi},
  journal= {arXiv preprint arXiv:2601.13917},
  year   = {2026}
}

Comments

The proof for Lemma 2.3 in the previous version is incorrect. In the new version the same assertion appears as Proposition 2.7 with corrected proof. The article has been reorganized. 9 pages. Comments welcome!