# Surface potential

The potential of a measure that is concentrated on a certain surface. Two forms of a surface potential are used in handling major boundary value problems in potential theory: the simple-layer potential

$$V(x)=\int\limits_S\frac{\mu(y)}{|y-x|}dS_y$$

produced by a measure distributed on a surface $S$ with density $\mu(y)$, $y\in S$; and the double-layer potential

$$W(x)=\int\limits_S\nu(y)\frac{\partial}{\partial n_y}\frac{1}{|y-x|}dS_y$$

produced by a measure distributed on $S$ with density $\nu(y)$. Physically, a simple-layer potential is interpreted as the potential of electrical charges with density $\mu(y)$, and a double-layer potential is the potential of dipoles with density $\nu(y)$ (see also Multi-pole potential).