Regularisation by regular noise (2009.08418v2)

Abstract: We show that perturbing ill-posed differential equations with (potentially very) smooth random processes can restore well-posedness -- even if the perturbation is (potentially much) more regular than the drift component of the solution. The noise considered is of fractional Brownian type, and the familiar regularity condition $\alpha>1-1/(2H)$ is recovered for all non-integer $H>1$.