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Metastable SUSY Breaking in the Cooling Universe

Vadim Kaplunovsky (Texas)
04 July 2007, 11:50 - 12:25

We investigate the cosmological aspects of metastable SUSY breaking. Suppose a field theory has both supersymmetric and non-SUSY non-perturbative vacuum states, and the non-SUSY vacua are metastable but very long lived (10 billion years or more). In a Universe which starts at very high temperature and slowly cools down to low temperatures, how likely is that field theory is to end up in a metastable non-SUSY vacuum? We answer this question for the ISS model (Seiberg dual of SQCD) of metastable SUSY breaking. At high temperatures, this theory has only one phase where all scalars have zero VEVs, but at some critical temperature T_c there is a second-order (or weakly first order) transition into a magnetic Higgs phase, which eventually (as T?0) evolves into the metastable non-SUSY vacuum. The mesonic-VEV phase (which would become a SUSY vacuum for T?0) appears above T_c and becomes thermodynamically preferred somewhat below T_c, but the first-order transition into this phase never happens because it is always separated from the other phases by a very wide energy barrier. Thus, at the end of the Big Bang, the theory ends in the meta-stable SUSY-breaking vacuum, and will stay there until long after the present era. This result does not depend on the specific details of the ISS model but only on its general features. Therefore, we believe that most models of metastable SUSY breaking will behave in the same way: In the cooling Universe, they would end up in a metastable SUSY-breaking vacuum.
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