Wolff potential

Summary

The Wolff potential of a measure is a nonlinear potential that measures how much mass the measure puts near a point at all scales. At each scale a power $1/(p - 1)$ is applied before the scales are summed. For $p = 2$ it reduces to a Riesz potential, up to a constant factor. Hedberg and Wolff showed that it controls the energy of measures in nonlinear capacity theory. Kilpeläinen and Malý showed that it gives pointwise bounds for $p$-superharmonic functions in terms of their Riesz measure, a basic tool of nonlinear potential theory.