Mapping classical fields to quantum states

          @misc{ scivideos_PIRSA:09100093,
            doi = {10.48660/09100093},
            url = {https://pirsa.org/09100093},
            author = {Wharton, Kenneth},
            keywords = {Quantum Foundations},
            language = {en},
            title = {Mapping classical fields to quantum states },
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2009},
            month = {oct},
            note = {PIRSA:09100093 see, \url{https://scivideos.org/index.php/pirsa/09100093}}
          }
          

Abstract

Abstract: Efforts to extrapolate non-relativistic (NR) quantum mechanics to a covariant framework encounter well-known problems, implying that an alternate view of quantum states might be more compatible with relativity. This talk will reverse the usual extrapolation, and examine the NR limit of a real, classical scalar field. A complex scalar \psi that obeys the Schrodinger equation naturally falls out of the analysis. One can also replace the usual operator-based measurement theory with classical measurement theory on the scalar field, and examine the NR limit of this as well. In this limit, the local energy density of the field scales as |\psi|^2, adding credibility to this approach. With the added postulate that "all measurements correspond to boundary conditions that extremize the classical action" (see arXiv:0906.5409), additional quantitative comparisons emerge between this \psi and the standard quantum wavefunction. Uncertainty can then be introduced (along with a "collapse" due to Bayesian updating) by simply giving the classical scalar field two components instead of one, leading to an intriguing \psi-epistemic model.