A mechanism of double protection of the Higgs potential, by supersymmetry and by a global symmetry, is investigated in a class of supersymmetric models with the $SU(3{)}_C\times SU(3{)}_W\times U(1{)}_X$ gauge symmetry. The electroweak symmetry can be then broken with no fine-tuning at all.

• Received 14 October 2005

DOI:https://doi.org/10.1103/PhysRevLett.96.031801