Local well-posedness problem
In working with my collaborators to justify the diffusion equation resulted from wave turbulence systems dominated by non-local interactions, we need to prove the local well-posedness of some wave kinetic equation. The system under our consideration is a three-dimensional Majda-McLaughlin-Tabak ( MMT) equation, with its wave kinetic equation given in the form of $\frac{\partial n_k}{\partial t} = 4\pi {\large{\int}}_{\mathbb{R}^9} |k|^{2\beta} |k_1|^{2\beta} |k_2|^{2\beta} |k_3|^{2\beta} (n_1n_2n_3 + n_2n_3n_k - n_2n_1n_k - n_3n_1n_k)$ $\delta(k+k_1-k_2-k_3) \delta(\omega+\omega_1-\omega_2-\omega_3) dk_1dk_2dk_3$, with $k\in \mathbb{R}^3$ and $\omega=|k|^\alpha$. This equation describes the evolution of wave action spectrum as a result of four-wave interactions. I will not detail more about the physical meaning of the equation and notations used therein, because that will distract readers too much from the main theme of the post. Anyway, one ...