Weak Solutions of Deterministic and Stochastic Linear Functional Equations in HILBERT Spaces
Constantin Tudor · Mathematische Nachrichten · 1991
Abstract In the paper it is shown that weak solutions of linear deterministic and stochastic retarded equations in HILBERT spaces are given by a variation of constants formula. Also, in the deterministic case, a characterization of the unbounded operator appearing in the term without delay is given.