Inserted: 1 sep 2010
Last Updated: 14 nov 2012
Journal: Ann. Fac. Sci. Toulouse Math.
We study points of density $1/2$ of sets of finite perimeter in infinite-dimensional Gaussian spaces and prove that, as in the finite-dimensional theory, the surface measure is concentrated on this class of points. Here density $1/2$ is formulated in terms of the pointwise behaviour of the Ornstein-Uhlenbeck semigroup.