{ "id": "1805.02324", "version": "v1", "published": "2018-05-07T02:45:16.000Z", "updated": "2018-05-07T02:45:16.000Z", "title": "Regularity of Solutions of the Camassa-Holm Equations with Fractional Laplacian Viscosity", "authors": [ "Zaihui Gan", "Yong He", "Linghui Meng", "Yue Wang" ], "comment": "39 pages", "categories": [ "math.AP" ], "abstract": "We study the existence, uniqueness and regularity of solutions to the $n$-dimensional ($n=2,3$) Camassa-Holm equations with fractional Laplacian viscosity with smooth initial data. It is a coupled system between the Navier-Stokes equations with nonlocal viscosity and a Helmholtz equation. The main difficulty lies in establishing some a priori estimates for the fractional Laplacian viscosity. To achieve this, we need to explore suitable fractional-power Sobolev-type estimates, and bilinear estimates for fractional derivatives. Especially, for the critical case $\\displaystyle s=\\frac{n}{4}$ with $n=2,3$, we will make extra efforts for acquiring the expected estimates as obtained in the case $\\displaystyle \\frac{n}{4}