Does Time Emerge from Timeless Laws, or do Laws of Nature Emerge in Time?

          @misc{ pirsa_PIRSA:11100113,
            doi = {10.48660/11100113},
            url = {https://pirsa.org/11100113},
            author = {Smolin, Lee},
            keywords = {},
            language = {en},
            title = {Does Time Emerge from Timeless Laws, or do Laws of Nature Emerge in Time? },
            publisher = {Perimeter Institute},
            year = {2011},
            month = {oct},
            note = {PIRSA:11100113 see, \url{https://pirsa.org}}
          }
          

Abstract

The history of physics, from Galileo's spatialization of time to Einstein's block universe, and on to Julian Barbour's timeless quantum cosmology, tells a story by which time is demoted from a fundamental aspect of experience to an emergent illusion in a world held to be fundamentally timeless. The question I would like to address is, is this correct, or will the next stage in the development of physics require a rediscovery of time as a primary aspect of nature? One reason to bet on the reality of time is the strength of the argument of Pierce that laws of nature require explanation and that laws must evolve to be explained. This implies that time is prior to law, which means time cannot emerge from timeless law. This however raises a problem: is the evolution of law lawful? Are all laws effective and approximate? Is there a metalaw which governs the evolution of laws? If so, what selects the metalaw? One approach to this meta-laws dilemma is that the distinction between dynamical laws and the states they act on, which is absolute in most physical theories, is emergent. I present a simple model to illustrate this approach. This talk is partly based on joint work with Roberto Mangabeira Unger.