Inpotential theory, an area ofmathematics, adouble layer potential is a solution ofLaplace's equation corresponding to theelectrostatic ormagnetic potential associated to adipole distribution on a closed surfaceS in three-dimensions. Thus a double layer potentialu(x) is a scalar-valued function ofx ∈R3 given bywhereρ denotes the dipole distribution,∂/∂ν denotes the directional derivative in the direction of the outward unit normal in they variable, and dσ is the surface measure onS.