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On a class of 2-surface observables in general relativity

Laszlo B Szabados
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Abstract

The boundary conditions for canonical vacuum general relativity is investigated at the quasi-local level. It is shown that fixing the area element on the 2- surface S (rather than the induced 2-metric) is enough to have a well defined constraint algebra, and a well defined Poisson algebra of basic Hamiltonians parameterized by shifts that are tangent to and divergence-free on $. The evolution equations preserve these boundary conditions and the value of the basic Hamiltonian gives 2+2 covariant, gauge-invariant 2-surface observables. The meaning of these observables is also discussed.

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Laszlo B Szabados. 2006-02-16. On a class of 2-surface observables in general relativity. https://doi.org/10.1088/0264-9381%2F23%2F7%2F006

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