This project will support research on inverse problems in partial differential equations. In particular the research will focus on the impedance tomography problem, the problem of characterization of the Dirichlet to Neumann map, the inverse conductivity problem for anisotropic conductivities in dimensions greater than or equal to three, and related problems in inverse scattering and inverse problems that arise in differential geometry. When an electric potential is applied to the surface of a conducting body, the resulting current flux across the surface depends on the internal resistance of the body. For this reason, voltage and current measurements made on the boundary of an object can be used to probe the internal structure of the body. The problem is to determine as much information as possible about the internal resistivity from measurements of voltage potentials and corresponding current fluxes at the boundary. This problem, often referred to as impedance computed tomography or electrical impedance imaging, arose in geophysics from attempts to determine the composition of the earth. More recently, it has been proposed as a potentially valuable diagnostic tool for the medical and biological sciences.
