On a stochastic Trotter formula with application to spontaneous localization models

We consider the relation between so called continuous localization models - i.e. non-linear stochastic Schr"odinger evolutions - and the discrete GRW-model of wave function collapse. The former can be understood as scaling limit of the GRW process. The proof relies on a stochastic Trotter formula, which is of interest in its own right. Our Trotter formula also allows to complement results on existence theory of stochastic Schr"odinger evolutions by Holevo and Mora/Rebolledo.