The dual Yamada-Watanabe theorem for mild solutions to stochastic partial differential equations
Stefan Tappe
TL;DR
This paper establishes a dual Yamada–Watanabe theorem for mild solutions to semilinear SPDEs with path-dependent coefficients by employing the method of moving frame to lift the problem to an infinite-dimensional SDE on a dilated Hilbert space $\mathscr{H}$. It analyzes the connections between SPDE mild solutions and SDE solutions via the dilation, projections, and a lift mapping $F \in \hat{\mathscr{E}}(H)$, enabling a unified treatment of uniqueness notions. The main results show that, under joint uniqueness in law for a given initial distribution, pathwise uniqueness follows, and under delta-uniqueness in law plus the group extension, delta-pathwise uniqueness holds; a Yamada–Watanabe-type equivalence for mild solutions is derived. The framework encompasses cylindrical and trace-class noise and provides a versatile tool for proving existence and uniqueness results for a broad class of SPDEs with path-dependent coefficients.
Abstract
We provide the dual result of the Yamada-Watanabe theorem for mild solutions to semilinear stochastic partial differential equations with path-dependent coefficients. An essential tool is the so-called "method of the moving frame", which allows us to reduce the proof to infinite dimensional stochastic differential equations.
