Computing with necklaces on elliptic curves
Year: 2026
Type: article
Abstract: We present computational algorithms to work with points on the modular curve associated to the normaliser of a non-split Cartan group of prime level $p$. Rather than working with explicit equations, we represent these points using the moduli interpretation of necklaces in the $p$-torsion of elliptic curves. We use our methods to investigate for which primes $\ell\neq p$ two rational points with complex multiplication can have equal reduction modulo $\ell$.
Source: Mathematics of Computation
DOI: 10.1090/mcom/4279
Authors: Marusia Rebolledo, Christian Wuthrich
Language: English
Subfield: Geometry and Topology
Field: Mathematics
Domain: Physical Sciences
Open Access status: hybrid
OpenAlex ID: W4416697813
