Intermediate scales in supersymmetric GUTs:
The survival of the fittest
(Melfo, Alejandra; Aulakh, Charanjit S.; Bajc, Borut; Rasin, Andrija; Senjanovic, Goran)

We show that intermediate scales in supersymmetric grand unified theories may exist naturally. Their origin is traced to the violation of the survival principle: in supersymmetry internal symmetries often forbid cubic couplings in the superpotential. This leads to a plethora of light supermultiplets whose masses are generated only by higher dimensional operators and thus suppressed by the cut-off scale. These new states often carry exotic quantum numbers and may be, in some cases, accessible to experiments in the near future.