I have the SDE:
$$X_t=X_0+\int_0^t \sqrt{1-X_s^2}dW_s-\frac{1}{2}\int_0^t X_s ds$$
I get no strong solutions but a weak solution (only one I was able to find):
$$X_t=\text{cos}(W_t),$$
I wonder primarily two questions:
- Are there other weak solutions that distributionally differ?
- Is there any solution that works for all real $X_0$ (the above solution requires $X_0$ is 1).