English

N\'eron models of pseudo-Abelian varieties

Number Theory 2021-10-26 v2

Abstract

We study N\'eron models of pseudo-Abelian varieties over excellent discrete valuation rings of equal characteristic p>0p>0 and generalize the notions of good reduction and semiabelian reduction to such algebraic groups. We prove that the well-known representation-theoretic criteria for good and semiabelian reduction due to N\'eron-Ogg-Shafarevich and Grothendieck carry over to the pseudo-Abelian case, and give examples to show that our results are the best possible in most cases. Finally, we study the order of the group scheme of connected components of the N\'eron model in the pseudo-Abelian case. Our method is able to control the \ell-part (for p\ell\not=p) of this order completely, and we study the pp-part in a particular (but still reasonably general) situation.

Keywords

Cite

@article{arxiv.2003.03764,
  title  = {N\'eron models of pseudo-Abelian varieties},
  author = {Otto Overkamp},
  journal= {arXiv preprint arXiv:2003.03764},
  year   = {2021}
}

Comments

31 pages. Small Addition to the proof of Proposition 3.3