Differential Harnack Estimates for the Filtration Equations on Riemannian Manifolds via Nash--Moser Iteration
We prove local differential Harnack estimates for smooth positive solutions of the Filtration Equations $u_t=\Delta F(u)$ on complete Riemannian manifolds in uniformly parabolic ranges. A Bochner--discriminant argument gives a coercive positive-part inequality, which is closed by Nash--Moser iteration. We derive Harnack and Liouville consequences, recover the Aronson-B\'enilan estimates for porous medium equation and fast diffusion equation, and describe a class of genuinely non-power filtration laws.