L-values of elliptic curves twisted by cubic characters

Abstract

Given a rational elliptic curve $ E $ of analytic rank zero, its L-function can be twisted by an even primitive Dirichlet character $ \chi $ of order $ q $, and in many cases its associated central algebraic L-value $ \mathcal{L}(E, \chi) $ is known to be integral. This paper derives some arithmetic consequences from a congruence between $ \mathcal{L}(E, 1) $ and $ \mathcal{L}(E, \chi) $ arising from this integrality, with an emphasis on cubic characters $ \chi $. These include $ q $-adic valuations of the denominator of $ \mathcal{L}(E, 1) $, determination of $ \mathcal{L}(E, \chi) $ in terms of Birch--Swinnerton-Dyer invariants, and asymptotic densities of $ \mathcal{L}(E, \chi) $ modulo $ q $ by varying $ \chi $.