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arXiv · 1612.05622

Factor Ordering and Path Integral Measure for Quantum Gravity in (1+1) Dimensions

Abstract

We develop a mathematically rigorous path integral representation of the time evolution operator for a model of (1+1) quantum gravity that incorporates factor ordering ambiguity. In obtaining a suitable integral kernel for the time-evolution operator, one requires that the corresponding Hamiltonian is self-adjoint; this issue is subtle for a particular category of factor orderings. We identify and parametrize a complete set of self-adjoint extensions and provide a canonical description of these extensions in terms of boundary conditions. Moreover, we use Trotter-type product formulae to construct path-integral representations of time evolution.

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BibTeXRIS

John Haga, Rachel Lash Maitra. 2017-06-07. Factor Ordering and Path Integral Measure for Quantum Gravity in (1+1) Dimensions. https://doi.org/10.3842/sigma.2017.039

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