Dyons near the Planck scale
  In the present letter we suggest a new model of preons-dyons making composite quark-leptons and bosons, described by the supersymmetric string-inspired flipped E_6\times \tilde E_6 gauge group of symmetry. This investigation predicts the possible extension of the Standard Model to the Family replicated gauge group model of type G^{N_{fam}}, where N_{fam} is the number of families. Here E_6 and \tilde E_6 are non-dual and dual sectors of theory with hyper-electric g and hyper-magnetic \tilde g charges, respectively. Our model is based on the recent theory of composite non-Abelian flux tubes in SQCD. Considering the breakdown of E_6 (and \tilde E_6) at the Planck scale into the SU(6)\times U(1) gauge group, we have shown that the six types of composite N = 1 supersymmetric non-Abelian flux tubes are created by the condensation of spreons-dyons near the Planck scale and have fluxes quantized according to the Z_6 center group of SU(6): \Phi_n = n\Phi_0 (n = \pm 1,\pm 2,\pm 3). These fluxes give three types of k-strings with tensions T_k = kT_0, where k = 1,2,3, and produce three generations of composite quark-leptons and bosons. Thus, the present model predicts N_{gen} = N_{fam} = 3. The condensation of spreons near the Planck scale gives the phase transition at scales M_{crit} and \tilde M_{crit}, and we have calculated the critical values of gauge coupling constants. 
Larisa Laperashvili and C.R. Das