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arXiv · 1112.3301

Local Hamiltonian for Spherically Symmetric Collapse: Geometrodynamics Approach

Jack Gegenberg·G. Kunstatter
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Abstract

Recently a {\it local} true (completely gauge fixed) Hamiltonian for spherically symmetric collapse was derived in terms of Ashtekar variables. We show that such a local Hamiltonian follows directly from the geometrodynamics of gravity theories that obey a Birkhoff theorem and possess a mass function that is constant on the constraint surface in vacuum. In addition to clarifying the geometrical content, our approach has the advantage that it can be directly applied to a large class of spherically symmetric and 2D gravity theories, including $p$-th order Lovelock gravity in D dimensions. The resulting expression for the true local Hamiltonian is universal and remarkably simple in form.

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Jack Gegenberg, G. Kunstatter. 2012-03-13. Local Hamiltonian for Spherically Symmetric Collapse: Geometrodynamics Approach. https://doi.org/10.1103/physrevd.85.084011

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