CBB is abbreviation for converged big bang which was found by dipole photon model to replace conventional big bang. As photon travels, pair particles of dipole photon shows relaxation which we call dopler red shift. so, red shift is merely related with the travel distance of photon. However, It is not sufficient to explain why Bing Bang is importantly cited in the society. CBB is developed for the unsatisfied people for dipole photon model.