English

Refined uniqueness results for 2D Euler and gSQG with rough Kraichnan noise

Probability 2026-01-12 v1 Analysis of PDEs

Abstract

We prove strong well-posedness results for the stochastic 2D Euler equations in vorticity form and generalized SQG equations, with LpL^p initial data and driven by a spatially rough, incompressible transport noise of Kraichnan type. Previous works addressed this problem with noise of spatial regularity α(0,1/2)\alpha\in (0,1/2), in a setting where a rougher noise yields a stronger regularization. We remove this limitation by allowing any α(0,1)\alpha \in (0,1), covering the same range of parameters for which anomalous regularization effects are known to occur in passive scalars. In particular, this covers the physically relevant case α=2/3\alpha=2/3, associated with the Richardson-Kolmogorov scaling of energy cascade.

Keywords

Cite

@article{arxiv.2601.05982,
  title  = {Refined uniqueness results for 2D Euler and gSQG with rough Kraichnan noise},
  author = {Marco Bagnara and Lucio Galeati},
  journal= {arXiv preprint arXiv:2601.05982},
  year   = {2026}
}