Schrödinger operator Partial differential equations Elliptic equations and systems : Recent advances in harmonic analysis and partial differential equations : AMS special sessions, March 12-13, 2011, Statesboro, Georgia : the JAMI Conference, March 21-25, 2011, Baltimore, Maryland / Andrea R. Nahmod, Christopher D. Sogge, Xiaoyi Zhang, Shijun Zheng, editors