# Schrodinger Evolution for the Universe: Reparametrization

@article{Gryb2015SchrodingerEF, title={Schrodinger Evolution for the Universe: Reparametrization}, author={Sean B. Gryb and Karim P. Y. Th{\'e}bault}, journal={Classical and Quantum Gravity}, year={2015}, volume={33}, pages={065004} }

Starting from a generalized Hamilton-Jacobi formalism, we develop a new framework for constructing observables and their evolution in theories invariant under global time reparametrizations. Our proposal relaxes the usual Dirac prescription for the observables of a totally constrained system (`perennials') and allows one to recover the influential partial and complete observables approach in a particular limit. Difficulties such as the non-unitary evolution of the complete observables in terms…

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