The recent discovery of the putative 125-GeV Higgs boson has motivated anumber of attempts to reconcile its relatively large mass with the predictionsof the minimal supersymmetric standard model (MSSM). Some approaches invokedlarge trilinear supersymmetry-breaking terms A_t between stops and one of theelementary Higgs fields. We consider the possibility that electroweak symmetrybreaking may be triggered by supersymmetry breaking with a large A_t, largeenough to generate a composite field with the same quantum numbers as the Higgsboson and with a non-vanishing vacuum expectation value. In the resultingvacuum, the usual relation between the gauge couplings and the Higgsself-coupling does not apply, and there is no reason to expect the same upperbound on the mass of the lightest Higgs boson. In a simple model where thebound state is assumed to have no mixing with the other fields, we calculatethe critical coupling A_t necessary for symmetry breaking using thelowest-order Bethe-Salpeter (BS) equation. Study of the BS equation iscomplicated by the structure of its lowest-order kernel, which is a crossed boxgraph, but we find an accurate approximation to its solution. In a realisticmodel, the mixing of the bound state with the fundamental Higgs boson creates asymmetry-breaking seesaw. We outline the steps toward a realistic model.
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