Abstract: A composite model of fermions based on three-flavoured preons is presented. It is shown that the opposite character of interactions between preons leads to formation of complex structures reproducing three generations of quarks and leptons with all their quantum numbers and masses. The model is self-consistent (it doesn’t use input parameters). Nevertheless, the masses of the generate...

A Coherent Potential Approximation is developed for s–wave and d–wave superconductivity in disordered systems. We show that the CPA formalism reproduces the standard pair-breaking formula, the self-consistent Born Approximation and the self-consistent T -matrix approximation in the appropriate limits. We implement the theory and compute Tc for s–wave and d–wave pairing using an attractive neare...