41 research outputs found
On the equivariant Tamagawa number conjecture for Tate motives and unconditional annihilation results
Let L/K be a finite Galois extension of number fields with Galois group G.
Let p be a rational prime and let r be a non-positive integer. By examining the
structure of the p-adic group ring Z_p[G], we prove many new cases of the
p-part of the equivariant Tamagawa number conjecture (ETNC) for the pair
(h^0(Spec(L)(r),Z[G])). The same methods can also be applied to other
conjectures concerning the vanishing of certain elements in relative algebraic
K-groups. We then prove a conjecture of Burns concerning the annihilation of
class groups as Galois modules for a wide class of interesting extensions,
including cases in which the full ETNC in not known. Similarly, we construct
annihilators of higher dimensional algebraic K-groups of the ring of integers
in L.Comment: 33 pages, error in section 3.4 corrected. To appear in Transactions
of the AM
On Mordell–Weil groups and congruences between derivatives of twisted Hasse–Weil L-functions
Let A be an abelian variety defined over a number field k and let F be a finite Galois extension of k. Let p be a prime number. Then under certain not-too-stringent conditions on A and F we compute explicitly the algebraic part of the p-component of the equivariant Tamagawa number of the pair (h1(A/F)(1),Z[Gal(F/k)]). By comparing the result of this computation with the theorem of Gross and Zagier we are able to give the first verification of the p-component of the equivariant Tamagawa number conjecture for an abelian variety in the technically most demanding case in which the relevant Mordell–Weil group has strictly positive rank and the relevant field extension is both non-abelian and of degree divisible by p. More generally, our approach leads us to the formulation of certain precise families of conjectural p-adic congruences between the values at s = 1 of derivatives of the Hasse–Weil L-functions associated to twists of A, normalised by a product of explicit equivariant regulators and periods, and to explicit predictions concerning the Galois structure of Tate–Shafarevich groups. In several interesting cases we provide theoretical and numerical evidence in support of these more general predictions
On the p-adic Stark conjecture at s=1 and applications
This is the author accepted manuscript. The final version is available from the London Mathematical Society via the DOI in this recordIncludes appendix by Tommy Hofmann, Henri Johnston and Andreas NickelLet E/F be a finite Galois extension of totally real number fields and let p be a prime. The `p-adic Stark conjecture at s=1' relates the leading terms at s=1 of p-adic Artin L-functions to those of the complex Artin L-functions attached to E/F. We prove this conjecture unconditionally when E/Q is abelian. We also show that for certain non-abelian extensions E/F the p-adic Stark conjecture at s=1 is implied by Leopoldt's conjecture for E at p. Moreover, we prove that for a fixed prime p, the p-adic Stark conjecture at s=1 for E/F implies Stark's conjecture at s=1 for E/F. This leads to a `prime-by-prime' descent theorem for the `equivariant Tamagawa number conjecture' (ETNC) for Tate motives at s=1. As an application of these results, we provide strong new evidence for special cases of the ETNC for Tate motives and the closely related `leading term conjectures' at s=0 and s=1.Engineering and Physical Sciences Research Council (EPSRC)DF
On a BSD-type formula for L-values of Artin twists of elliptic curves
This is an investigation into the possible existence and consequences of a
Birch-Swinnerton-Dyer-type formula for L-functions of elliptic curves twisted
by Artin representations. We translate expected properties of L-functions into
purely arithmetic predictions for elliptic curves, and show that these force
some peculiar properties of the Tate-Shafarevich group, which do not appear to
be tractable by traditional Selmer group techniques. In particular we exhibit
settings where the different p-primary components of the Tate-Shafarevich group
do not behave independently of one another. We also give examples of
"arithmetically identical" settings for elliptic curves twisted by Artin
representations, where the associated L-values can nonetheless differ, in
contrast to the classical Birch-Swinnerton-Dyer conjecture.Comment: 27 pages, new versio
SATO-TATE EQUIDISTRIBUTION OF CERTAIN FAMILIES OF ARTIN L-FUNCTIONS
We study various families of Artin L-functions attached to geometric parametrizations of number fields. In each case we find the Sato-Tate measure of the family and determine the symmetry type of the distribution of the low-lying zeros