Squareness in the special L-value and special L-values of twists
| dc.creator | Agashe, Amod | |
| dc.date | 2008-10-29 | |
| dc.date | 2009-05-26 | |
| dc.date.accessioned | 2026-07-07T13:17:41Z | |
| dc.date.available | 2026-07-07T13:17:41Z | |
| dc.description | Let N be a prime and let A be a quotient of J_0(N) over Q associated to a newform such that the special L-value of A (at s=1) is non-zero. Suppose that the algebraic part of the special L-value of A is divisible by an odd prime q such that q does not divide the numerator of (N-1)/12. Then the Birch and Swinnerton-Dyer conjecture predicts that the q-adic valuations of the algebraic part of the special L-value of A and of the order of the Shafarevich-Tate group are both positive even numbers. Under a certain mod q non-vanishing hypothesis on special L-values of twists of A, we show that the q-adic valuations of the algebraic part of the special L-value of A and of the Birch and Swinnerton-Dyer conjectural order of the Shafarevich-Tate group of A are both positive even numbers. We also give a formula for the algebraic part of the special L-value of A over quadratic imaginary fields K in terms of the free abelian group on isomorphism classes of supersingular elliptic curves in characteristic N (equivalently, over conjugacy classes of maximal orders in the definite quaternion algebra over Q ramified at N and infinity) which shows that this algebraic part is a perfect square up to powers of the prime two and of primes dividing the discriminant of K. Finally, for an optimal elliptic curve E, we give a formula for the special L-value of the twist E_D of E by a negative fundamental discriminant -D, which shows that this special L-value is an integer up to a power of 2, under some hypotheses. In view of the second part of the Birch and Swinnerton-Dyer conjecture, this leads us to the surprising conjecture that the square of the order of the torsion subgroup of E_D divides the product of the order of the Shafarevich-Tate group of E_D and the orders of the arithmetic component groups of E_D, under certain mild hypotheses. | |
| dc.identifier | https://arxiv.org/abs/0810.5179 | |
| dc.identifier | http://arxiv.org/abs/0810.5179 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/231193 | |
| dc.subject | Number Theory | |
| dc.subject | Algebraic Geometry | |
| dc.subject | 11G40; 14G99 | |
| dc.title | Squareness in the special L-value and special L-values of twists | |
| dc.type | text |