In potential theory, an area of mathematics, a double layer potential is a solution of Laplace's equation corresponding to the electrostatic or magnetic potential associated to a dipole distribution on a closed surface S in three-dimensions. Thus a double layer potential is a scalar-valued function of given by
where àdenotes the dipole distribution, âÂÂ/âÂÂý denotes the directional derivative in the direction of the outward unit normal in the y variable, and dàis the surface measure on S.
More generally, a double layer potential is associated to a hypersurface S in n-dimensional Euclidean space by means of
where P(y) is the Newtonian kernel in n dimensions.