Abstract:
This report first describes the debate on whether there is an accelerating expansion of the Universe. Secondly, using nucleon decay catalysed by magnetic monopole as an energy source, it will cause a thermal explosion of the whole Universe when the Universe contracts to a high density, and the luminosity produced by magnetic monopole catalyseddecay is much larger than the Eddington luminosity, which is the stability limit of the whole Universe. This leads us to propose a model for the evolution of the universe as a whole: an oscillatory model with alternating expansion and contraction.