Gradient estimates for the porous medium type equations and fast diffusion type equations on complete noncompact metric measure space with compact boundary

Abstract

In the paper, we derive Li-Yau gradient estimates and Souplet Zhang type estimates of the following equation \begin{equation*} \begin{split} u_t= \Delta_\xi p+\lambda u+A(u) , \end{split} \end{equation*} on complete noncompact metric measure space $ (M, g,e^{-\xi}dv_g) $ with compact boundary. We will also give the local gradient estimates of the equation \begin{equation*} \Delta_\xi(u^p)+\lambda u+A(u)=0, \end{equation*} on complete noncompact manifold with compact boundary.