2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/72211We consider a Yamabe type problem on a family $A_ε$ of annulus shaped domains of $\R^3$ which becomes "thin" as $ε$ goes to zero. We show that, for any given positive constant $C$, there exists $ε_0$ such that for any $ε< ε_0$, the problem has no solution $u_ε$ whose energy is less than $C$. Such a result extends to dimension three a result previously known in higher dimensions. Although the strategy to prove this result is the same as in higher dimensions, we need a more careful and delicate blow up analysis of asymptotic profiles of solutions $u_ε$ when $ε$ goes to zero.24 pagesAnalysis of PDEs35J65, 58E05, 35B40text