The equations that represent all known fundamental laws of nature are invariant under time reversal. However, it is a fact that real processes are irreversible. The origin of such changes and the existence of an asymmetry in time have been a source of perplexity for physicists and philosophers alike. In this talk I will review the history of this problem and I will propose a solution based on a global-to-local coupling between the dynamic of spacetime and the electromagnetic phenomena occurring at each point of the universe.