2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/154813An embedding of the group $\Diff(S^{1})$ of orientation preserving diffeomorphims of the unit circle $S^1$ into an infinite-dimensional symplectic group, $\Sp(\infty)$, is studied. The authors prove that this embedding is not surjective. A Brownian motion is constructed on $\Sp(\infty)$. This study is motivated by recent work of H. Airault, S. Fang and P. Malliavin.ProbabilityDifferential GeometryDiffeomorphisms of the circle and Brownian motions on an infinite-dimensional symplectic grouptext