| Contents |
| We study the existence of subharmonic solutions of the capillarity equation
$$-\Big( u'/{ \sqrt{1+{u'}^2}}\Big)'= f(t,u).$$
According to the specific structure of the curvature operator and to the behaviour of $f$ at infinity and at zero, we get the existence of arbitrarily large bounded variation subharmonic solutions, or arbitrarily small classical subharmonic solutions.
The method of proof relies on the use of non-smooth critical point theory in the former case and on the Poincar\'e-Birkhoff theorem in the latter one. |
|