Non-universalities in Supergravity Grand Unification

Non-universalities in the soft SUSY breaking parameters within grand unification are investigated. In general non-universalities contain effects of Planck physics and are sensitive to physics between the GUT scale and the Planck/string scale. The effect of the top Landau pole on the non-universalities in the Higgs sector are discussed. A class of models are investigated where it is shown that the non-universalities at the GUT scale depend upon on both the grand unification group and the particle spectrum in the post GUT region, different assumptions giving rise to different phenomena. Thus the sparticle spectrum at low energy will be sensitive not only to GUT physics but also to physics up to the string scale. The possibilities of experimentally probing the post GUT domain at LHC and at linear colliders using various sum rules is described.