On the cuspidality of pullbacks of Siegel Eisenstein series and applications to the Bloch-Kato conjecture
arXiv:0712.2227
Abstract
Let be an integer and a prime with . Let be a newform of weight and level 1 so that is ordinary at and is irreducible. Under some additional hypotheses we prove that $ord_{p}(L_{alg}(k,f)) \leq ord_{p}(# S)$ where is the Pontryagin dual of the Selmer group associated to with the -adic cyclotomic character. We accomplish this by first constructing a congruence between the Saito-Kurokawa lift of and a non-CAP Siegel cusp form. Once this congruence is established, we use Galois representations to obtain the lower bound on the Selmer group.
33 pages