Heterotic String Optical Unification

The lower limit to string coupling unification in weakly coupled heteroticstrings was shown by Kaplunovsky to be around ΛH ∼ 5 × 1017 GeV. Incontrast, under the scenario of an intermediate scale desert, the SU(3)C ×SU(2)L × U(1)Y ([321]) Minimal Supersymmetric Standard Model (MSSM)unification scale is ΛU ∼ 2.5 × 1016 GeV. Optical unification was proposed by Giedt as a robust mechanism for relating these two scales. In this mechanism,intermediate scale MSSM-charged exotic particles effect running couplings like a diverging lens, always producing a “virtual” image of the string unificationpoint between the string scale and the exotic particle mass scale. A heterotic string model that offers the potential to realize optical unification was recentlyconstructed. This paper reports the initial results of an investigation into the possibility of optical unification realization in this model. This paper is a product of the NSF REU program at Baylor University and is based on a talk presented at the Second International Conference on String Phenomenology, Durham, England, 29 July 4 August, 2003.