A note on L-packets and abelian varieties over local fields
Number Theory
2020-02-27 v2 Representation Theory
Abstract
A polarized abelian variety (X,\lambda) of dimension g over a local field K determines an admissible representation of GSpin_{2g+1}(K). We show that the restriction of this representation to Spin_{2g+1}(K) is reducible if and only if X is isogenous to its twist by the quadratic unramified extension of K. When g=1 and K = Q_p, we recover the well-known fact that the admissible GL_2(K) representation attached to an elliptic curve E is reducible upon restriction to SL_2(K) if and only if E has supersingular reduction.
Cite
@article{arxiv.1402.4082,
title = {A note on L-packets and abelian varieties over local fields},
author = {Jeff Achter and Clifton Cunningham},
journal= {arXiv preprint arXiv:1402.4082},
year = {2020}
}