Closability of Quadratic Forms Associated to Invariant Probability   Measures of SPDEs
  By using the integration by parts formula of a Markov operator, the closability of quadratic forms associated to the corresponding invariant probability measure is proved. The general result is applied to the study of semilinear SPDEs, infinite-dimensional stochastic Hamiltonian systems, and semilinear SPDEs with delay. 
Michael Rockner, Feng-Yu Wang
math.PR