Pathwise closeness of solutions of SDE's

46 Views Asked by At

Given two SDE's with random diffusion coefficients, if the diffusion coefficients are pathwise uniformly close, can we say the same about the solutions to corresponding SDE's?

More precisely, consider $$ dX^1_t = b(X^1_t) dt + \sigma^1 \cdot \nu (X^1_t) dW $$ and $$ dX^2_t = b(X^2_t) dt + \sigma^2 \cdot \nu (X^2_t) dW $$ where $\sigma^1$ and $\sigma^2$ are continuous processes.

Is it possible to say that, for all $T \leq \infty$ and $\epsilon > 0$, there exists $\delta > 0$ such that $$ P(\sup_{0 \leq u \leq T} |\sigma^1_u - \sigma^2_u| > \delta) < \delta \Rightarrow P(\sup_{0 \leq u \leq T} |X^1_u - X^2_u| > \epsilon) < \epsilon? $$

(Assume integrability and growth conditions on $b, \nu, \sigma^1$ and $\sigma^2$ to ensure strong existence and uniqueness of $X^1$ and $X^2$.)