Horizontal $p$-adic $L$-functions
Daniel Kriz, Asbjørn Christian Nordentoft
TL;DR
The paper constructs horizontal $p$-adic $L$-functions attached to twists of elliptic curves by $p$-power order characters and develops a horizontal Iwasawa-theoretic framework to study their zeros. By expressing central $L$-values via Birch--Stevens-type modular-symbol expansions and encoding them into horizontal measures, the authors prove strong non-vanishing results, including quantitative lower bounds and simultaneous non-vanishing for multiple curves. A key innovation is a horizontal analogue of Weierstrass preparation supported by a Fourier-analytic structure on non-noetherian horizontal Iwasawa algebras, together with a global-to-local norm-relations machinery. Conditional on mod $p$ Kurihara conjectures (and benefiting from recent progress) they obtain pervasive non-vanishing results for twists of general order, with explicit density and growth-parameter statements, providing new evidence toward conjectures of Goldfeld and related Diophantine stability phenomena.
Abstract
We define new objects called 'horizontal $p$-adic $L$-functions' associated to $L$-values of twists of elliptic curves over $\mathbb{Q}$ by characters of $p$-power order and conductor prime to $p$. We study the fundamental properties of these objects and obtain applications to non-vanishing of finite order twists of central $L$-values, making progress toward conjectures of Goldfeld and David--Fearnley--Kisilevsky. For general elliptic curves $E$ over $\mathbb{Q}$ we obtain strong quantitative lower bounds on the number of non-vanishing central $L$-values of twists by Dirichlet characters of fixed order $d\equiv 2 \mod 4$ greater than two. We also obtain non-vanishing results for general $d$, including $d = 2$, under mild assumptions. In particular, for elliptic curves with $E[2](\mathbb{Q}) = 0$ we improve on the previously best known lower bounds on the number of non-vanishing $L$-values of quadratic twists due to Ono. Finally, we obtain results on simultaneous non-vanishing of twists of an arbitrary number of elliptic curves with applications to Diophantine stability.
