Phenomenological viability of string and M-theory scenarios Original Research Article

We analyze the constraints that a correct phenomenology and the absence of dangerous charge and colour breaking (CCB) minima or unbounded from below (UFB) directions impose on the parameter space of different superstring and M-theory scenarios. Namely, we analyze in detail the case where supersymmetry (SUSY) breaking is driven by non-vanishing dilaton and/or moduli F-terms in weakly and strongly coupled strings, and the specific case where the mechanism of SUSY breaking is gaugino condensation with or without the participation of non-perturbative contributions to the Kähler potential. The results indicate that, only in some small windows of the parameter space all the previous tests are successfully passed. We also discuss the impact of non-universality of the soft breaking terms on CCB/UFB bounds.