Gravity and BF theory defined in bounded regions

Viqar Husain; Seth Major

doi:10.1016/s0550-3213(97)00371-4

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arXiv · gr-qc/9703043

Gravity and BF theory defined in bounded regions

Viqar Husain·Seth Major

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Abstract

We study Einstein gravity in a finite spatial region. By requiring a well-defined variational principle, we identify all local boundary conditions, derive surface observables, and compute their algebra. The observables arise as induced surface terms, which contribute to a non-vanishing Hamiltonian. Unlike the asymptotically flat case, we find that there are an infinite number of surface observables. We give a similar analysis for SU(2) BF theory.

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Viqar Husain, Seth Major. 1997-04-02. Gravity and BF theory defined in bounded regions. https://doi.org/10.1016/s0550-3213(97)00371-4

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