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We consider a string-inspired, gravitational theory of scalar and electromagnetic fields and we investigate the existence of axially-symmetric, Gödel-type cosmological solutions. The neutral case is studied first and an "extreme" Gödel-type rotating solution, that respects the causality, is determined. The charged case is considered next and two new configurations for the, minimally-coupled to gravity, electromagnetic field are presented. Another configuration motivated by the expected distribution of currents and charges in a rotating universe is studied and shown to lead to a Gödel-type solution for a space-dependent coupling function. Finally, we investigate the existence of Gödel-type cosmological solutions in the framework of the one-loop corrected superstring effective action and we determine the sole configuration of the electromagnetic field that leads to such a solution. It turns out that, in all the charged cases considered, Closed Timelike Curves do appear and the causality is always violated.

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The results for the running of the gauge couplings in the MSSM are up-dated by proper inclusion of all low scale effects. They are presented as predictions for the strong coupling constant in the scenario with only two parameters at the GUT scale (α U and M U ) and as a mismatch of the couplings at the scales ∼ 3 × 10 16 GeV and 4 × 10 17 GeV, when all three couplings are taken as the experimental input.