Phenomenological viability of string and M-theory scenarios

Abstract

We analyze the constraints that a correct phenomenology and the absence of dangerous charge and color 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 K{\"a}hler potential. The results indicate that, only in some small windows of the parameter space all the previous tests are succesfully passed. We also discuss the impact of non-universality of the soft breaking terms on CCB/UFB bounds.Comment: 18 pages + 10 figures, PostScript fil