##
**Solutions of a stochastic differential equation forced onto a manifold by a large drift.**
*(English)*
Zbl 0749.60053

It is considered a sequence of \(R^ d\)-valued semimartingales \(X_ n\) satisfying
\[
X_ n(t)=X_ n(0)+\int_ 0^ t\sigma_ n(X_ n(s- ))dZ_ n(s)+\int_ 0^ t F(X_ n(s-))dA_ n(s),
\]
where \(Z_ n\) is a sequence of \(R^ k\)-valued semimartingales, \(\sigma_ n\) is a continuous \(d\times k\) matrix-valued function, \(F\) is a vector field whose deterministic flow has an asymptotically stable manifold of fixed points \(\Gamma\) and \(A_ n\) is a nondecreasing process. The author investigates stability of this system. Stability means, roughly speaking, if \(X_ n(0)\) is close to \(\Gamma\) (or is only in the domain of attraction of \(\Gamma\) under the flow of \(F\)) and \(X_ n\) is close to \(\Gamma\), then any limiting process is close to \(\Gamma\). There are given conditions under which a sequence \((X_ n)\) is relatively compact in the Skorokhod topology and which ensure the existence of a stochastic integral equation which any limiting process has to satisfy.

Reviewer: J.Jakubowski (Warszawa)

### MSC:

60H10 | Stochastic ordinary differential equations (aspects of stochastic analysis) |

60J60 | Diffusion processes |

60J70 | Applications of Brownian motions and diffusion theory (population genetics, absorption problems, etc.) |