English

On the Bernoulli--Hurwitz periods

Number Theory 2025-10-22 v1

Abstract

Let EE be an elliptic curve having CM by the ring of integers of an imaginary quadratic field KK in which pp splits. Following Lichtenbaum, the Bernoulli--Hurwitz numbers of EE (i.e., values of Eisenstein series evaluated at EE up to normalization) admit integral representations given by a pp-adic measure constructed from an elliptic function. We show that the periods of this measure are in fact special values of a family of weight one Eisenstein series at the CM curve EE equipped with certain level data, and explicitly relate it to Katz's one-variable pp-adic Eisenstein measure, whereby we derive period formulas of the Bernoulli--Hurwitz measure attached to any ordinary elliptic curve E\mathcal{E} defined over a local field. Moreover, by exploiting the modularity of these periods, and thanks to the existence of abundant weight one Hasse-type invariants, we present a novel approach to the interpolation property of the Bernoulli--Hurwitz pp-adic zeta functions of the ordinary elliptic curve E\mathcal{E}, and obtain a pp-adic Kronecker's first limit formula.

Keywords

Cite

@article{arxiv.2510.17939,
  title  = {On the Bernoulli--Hurwitz periods},
  author = {Luochen Zhao},
  journal= {arXiv preprint arXiv:2510.17939},
  year   = {2025}
}

Comments

38 pages, comments welcome!