2 problems

Let the ambient space be $\mathbb{R}^{d+1}$, with absorbing boundary identified with $\mathbb{R}^d$. Write $\boldsymbol{r}$ for the displacement along the boundary, let $\lambda>0$…

Let $f_\epsilon$ be the non-negative solution of the kinetic equation in the preceding theorem, and let $f_0=\rho_0(t,x)Q_0(y,v)$ be its formal asymptotic limit, where $\rho_0$ sat…