A nonlinear Schr\"odinger equation with fractional noise
Abstract
We study a stochastic Schr\"odinger equation with a quadratic nonlinearity and a space-time fractional perturbation, in space dimension less than 3. When the Hurst index is large enough, we prove local well-posedness of the problem using classical arguments. However, for a small Hurst index, even the interpretation of the equation needs some care. In this case, a renormalization procedure must come into the picture, leading to a Wick-type interpretation of the model. Our fixed-point argument then involves some specific regularization properties of the Schr\"odinger group, which allows us to cope with the strong irregularity of the solution.
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