English

Formal completions of N\'eron models for algebraic tori

Algebraic Geometry 2009-11-19 v3 Number Theory

Abstract

We calculate the formal group law which represents the completion of the N\'eron model of an algebraic torus over the rationals that splits in a tamely ramified abelian extension. As a tools in the proof, we define and give criterions to compute the Weil restriction of a formal group law and the analog of the fixed part of a formal group law with respect to the action of a (finite) group.

Keywords

Cite

@article{arxiv.0704.2578,
  title  = {Formal completions of N\'eron models for algebraic tori},
  author = {Oleg Demchenko and Alexander Gurevich and Xavier Xarles},
  journal= {arXiv preprint arXiv:0704.2578},
  year   = {2009}
}

Comments

35 pages. New version with new functoriality results. Final version in the Proceedings of the London Mathematical Society, link: http://plms.oxfordjournals.org/cgi/content/abstract/pdp039?ijkey=NVyJlz51HbzrzxM&keytype=ref