Sea quark contributions to the electric polarizability of hadrons

We present a lattice QCD calculation of the polarizability of the neutron and other neutral hadrons that includes the effects of the background field on the sea quarks. This is done by perturbatively reweighting the charges of the sea quarks to couple them to the background field. The main challenge in such a calculation is stochastic estimation of the weight factors, and we discuss the difficulties in this estimation. Here we use an extremely aggressive dilution scheme to reduce the stochastic noise to a manageable level. The pion mass in our calculation is 300 MeV and the lattice size is 3 fm. For the neutron, we find that alpha(E) = 2.70(55) x 10(-4) fm(3), which is the most precise lattice QCD determination of the polarizability to date that includes sea effects.