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The Gravitational Hamiltonian in the Presence of Non-Orthogonal Boundaries

S. W. Hawking·C. J. Hunter
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Abstract

This paper generalizes earlier work on Hamiltonian boundary terms by omitting the requirement that the spacelike hypersurfaces $Σ_t$ intersect the timelike boundary $\cal B$ orthogonally. The expressions for the action and Hamiltonian are calculated and the required subtraction of a background contribution is discussed. The new features of a Hamiltonian formulation with non-orthogonal boundaries are then illustrated in two examples.

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S. W. Hawking, C. J. Hunter. 1996-08-27. The Gravitational Hamiltonian in the Presence of Non-Orthogonal Boundaries. https://doi.org/10.1088/0264-9381%2F13%2F10%2F012

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