Plectic Galois action on CM points and connected components of Hilbert modular varieties
Number Theory
2022-10-25 v3 Algebraic Geometry
Abstract
We expand on Nekov\'a\v{r}'s construction of the plectic half transfer to define a plectic Galois action on Hilbert modular varieties. More precisely, we study in a unifying fashion Shimura varieties associated to groups that differ only in the centre from . We define plectic Galois actions on the CM points and on the set of connected components of these Shimura varieties, and show that these two actions are compatible. This extends the plectic conjecture of Nekov\'a\v{r}--Scholl.
Keywords
Cite
@article{arxiv.2001.11097,
title = {Plectic Galois action on CM points and connected components of Hilbert modular varieties},
author = {Marius Leonhardt},
journal= {arXiv preprint arXiv:2001.11097},
year = {2022}
}
Comments
This is the version to appear in Bull. Lond. Math. Soc., https://doi.org/10.1112/blms.12692. The start of Section 2.3 has been rewritten to expand on the moduli space interpretation of Hilbert modular varieties. Comments welcome!