Decoherence and Effective Field Theories

          @misc{ scivideos_PIRSA:11100121,
            doi = {10.48660/11100121},
            url = {https://pirsa.org/11100121},
            author = {Stamp, Philip},
            keywords = {},
            language = {en},
            title = {Decoherence and Effective Field Theories},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2011},
            month = {oct},
            note = {PIRSA:11100121 see, \url{https://scivideos.org/index.php/pirsa/11100121}}
          }
          

Abstract

Effective field theories, underpinned by the resnormalization framework, are a central feature of condensed matter physics and relativistic field theory. However the phenomenon of decoherence is not so easily subsumed under this framework. Ordinary environmental decoherence may lead to very unusual effective theories, and recent ideas about intrinsic decoherence in Nature (eg., Penrose's ideas aobut gravitational decoherence) do not obviously lead to any effective field theory. I will review our ideas aobut environmental decoherence, with some examples from condensed matter physics, highlighting some of the peculiar features of these. I will then discuss what we know of intrinsic decoherence (which in some cases amounts to a breakdonw of quantum mechanics, focussing on a new path integral formulation of Penrose's ideas.