Dynamics of M-theory vacua

At very early times, the Universe was not in a vacuum state. Under the assumption that the deviation from equilibrium was large, in particular, that it is higher than the scale of inflation, we analyze the conditions for local transitions between states that are related to different vacua. All pathways lead to an attractor solution of a description of the Universe by eternal inflation with domains that have different low energy parameters. The generic case favors transitions between states that have significantly different parameters rather than jumps between nearby states in parameter space. I argue that the strong CP problem presents a potential difficulty for this picture, more difficult than the hierarchy problem or the cosmological constant problem. Finally, I describe how the spectrum of quark masses may be a probe of the early dynamics of vacuum states. As an example, by specializing to the case of intersecting braneworld models, I show that the observed mass spectrum, which is approximately scale invariant, corresponds to a flat distribution in the intersection area of the branes, with a maximum area A(max)similar to100alpha(').