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Gravitational Constraints which Generate a Lie Algebra

Karel V. Kuchar·Joseph D. Romano
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Abstract

The coupling of gravity to dust helps to discover simple quadratic combinations of the gravitational super-Hamiltonian and supermomentum whose Poisson brackets strongly vanish. This leads to a new form of vacuum constraints which generate a true Lie algebra. We show that the coupling of gravity to a massless scalar field leads to yet another set of constraints with the same property, albeit not as simple as that based on the coupling to dust.

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Karel V. Kuchar, Joseph D. Romano. 1995-01-09. Gravitational Constraints which Generate a Lie Algebra. https://doi.org/10.1103/physrevd.51.5579

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