Probability of the Standard Model Appearance from a Matrix Model

The standard model of particle physics lies in an enormous number of string vacua. In a nonperturbative formulation of string theory, various string vacua can, in principle, be compared dynamically, and the probability distribution over the vacuum space could be calculated. In this paper, we consider situations where the IIB matrix model is compactified on a six-dimensional torus with various gauge groups and various magnetic fluxes, find matrix configurations that provide the standard model matter content, and estimate semiclassically the probability of their appearance.