Eisenstein cocycles for imaginary quadratic fields
Number Theory
2025-04-29 v1
Abstract
We construct Eisenstein cocycles for arithmetic subgroups of GL_2 of imaginary quadratic fields valued in second K-groups of products of two CM elliptic curves. We use these to construct maps from the first homology groups of Bianchi spaces to corresponding second K-groups of ray class fields and to verify the Eisenstein property of these maps for prime-to-level Hecke operators.
Cite
@article{arxiv.2504.19125,
title = {Eisenstein cocycles for imaginary quadratic fields},
author = {Emmanuel Lecouturier and Romyar Sharifi and Sheng-Chi Shih and Jun Wang},
journal= {arXiv preprint arXiv:2504.19125},
year = {2025}
}
Comments
46 pages