English

Classification of the Mumford--Tate Groups of Rational Polarizable Hodge Structures

Algebraic Geometry 2023-05-10 v2

Abstract

Let G be the pro-algebraic group attached to the tannakian category of polarizable rational Hodge structures. We show that the quotient of G by its derived group is the Serre group, the derived group of G is the simply connected covering of the adjoint group of G, and that the adjoint group G is a product of specific simple algebraic groups. As the Mumford--Tate groups are exactly the algebraic quotients of G, this also describes them.

Keywords

Cite

@article{arxiv.2012.14063,
  title  = {Classification of the Mumford--Tate Groups of Rational Polarizable Hodge Structures},
  author = {James S. Milne},
  journal= {arXiv preprint arXiv:2012.14063},
  year   = {2023}
}

Comments

11 pages. v2 improved the exposition. arXiv admin note: text overlap with arXiv:1105.0887