Abstract:
Necessary and sufficient conditions are given for the possibility of a diffusion field defined by diffusion and transfer coefficients to be transformed into another field. The problem of transforming a diffusion field into a Gaussian continuous square integrable martingale and, in particular, into a Wiener field is investigated in detail.
Keywords:conditional independence of $\sigma$-algebras, Gaussian strong continuous martingales, square integrable martingales, Wiener fields, stochastic differential equations, equivalent diffusion fields, bidirected diffusion fields, the Itô, formula, invariance problem.