I just want to know for a soomth boundary domain whetherwith smooth boundary whether exterior Newtonian potential has singular analytic extension into the domain or into a part of the domiandomain.
Definition of Newtonian potential of domain $\Omega$ at x is defined to be $u(x)=\int_{R^{n}}\Gamma(|x-y|)\chi_{\Omega}(y)dy$. When $x\in \Omega$ we say it is the interior Newtonian potential, otherwise we call it exterior Newtonian potential. Here $\Gamma(x)=\frac{1}{|x|^{n-2}}$ is the fundamental solution of Laplace, $\chi_{\Omega}$ is the characterization fucntion of $\Omega$
For example, the exterior Newtonian potential of the ball $B(a,R)$ is just $\frac{R^{n-2}}{n(n-2)}\frac{1}{|x-a|^{n-2}}$ when $n>2$. Even though it is Newtonian potential of the ball out of it, we can regard it as a singular analytic function on $R^{n}$. So we can say the exterior newtonian potential of the ball have singular analytic extension in it.
Or in particular,: what is the exterior newtonianNewtonian potential of the domain which is formed by moving the center of a ball along a arbitrary small smooth curve.? Does this case allow singular analytic extension in the domain.?