English

Syntomic regulators of Asai--Flach classes

Number Theory 2021-01-27 v2

Abstract

In this paper, we derive a formula for the p-adic syntomic regulators of Asai--Flach classes. These are cohomology classes forming an Euler system associated to a Hilbert modular form over a quadratic field, introduced in an earlier paper (arXiv:1607.07813) by Antonio Lei and the first and third authors. The formula we develop here is expressed in terms of differential operators acting on overconvergent Hilbert modular forms; it is analogous to existing formulae for the regulators of Beilinson--Flach classes, but a novel feature is the appearance of a projection operator associated to a critical-slope Eisenstein series. We conclude the paper with numerical calculations giving strong evidence for the non-vanishing of these regulators in an explicit example.

Keywords

Cite

@article{arxiv.1608.06112,
  title  = {Syntomic regulators of Asai--Flach classes},
  author = {David Loeffler and Christopher Skinner and Sarah Livia Zerbes},
  journal= {arXiv preprint arXiv:1608.06112},
  year   = {2021}
}

Comments

Revised version: strengthened main theorem to avoid unnecessary assumptions, and added a formula for normalisation of Eisenstein functional

R2 v1 2026-06-22T15:26:08.725Z