| Abstract: |
| We present some results on the boundary behavior of solutions to fractional elliptic problems. In particular, we address the following problems: \
1) can one prove a Hopf-type lemma for possibly sign-changing solutions? \
2) given a non-trivial solution $u$, is it possible that $u$ has infinitely many zeros accumulating at the boundary? \
We answer these questions, and we provide concrete examples to show that the results obtained are sharp. |
|