# The gravitational Hamiltonian in the presence of non-orthogonal boundaries

@article{Hawking1996TheGH, title={The gravitational Hamiltonian in the presence of non-orthogonal boundaries}, author={Stephen William Hawking and C. J. Hunter}, journal={Classical and Quantum Gravity}, year={1996}, volume={13}, pages={2735-2752} }

This paper generalizes earlier work on Hamiltonian boundary terms by omitting the requirement that the spacelike hypersurfaces intersect the timelike boundary 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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