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arXiv · gr-qc/9601043

Action functionals of single scalar fields and arbitrary--weight gravitational constraints that generate a genuine Lie algebra

Ioannis Kouletsis
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Abstract

We discuss the issue initiated by Kuchař {\it et al}, of replacing the usual Hamiltonian constraint by alternative combinations of the gravitational constraints (scalar densities of arbitrary weight), whose Poisson brackets strongly vanish and cast the standard constraint-system for vacuum gravity into a form that generates a true Lie algebra. It is shown that any such combination---that satisfies certain reality conditions---may be derived from an action principle involving a single scalar field and a single Lagrange multiplier with a non--derivative coupling to gravity.

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Ioannis Kouletsis. 1996-01-26. Action functionals of single scalar fields and arbitrary--weight gravitational constraints that generate a genuine Lie algebra. https://doi.org/10.1088/0264-9381%2F13%2F11%2F022

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