Abstract
Recently, a 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 two-dimensional gravity theories, including th order Lovelock gravity in dimensions. The resulting expression for the true local Hamiltonian is universal and remarkably simple in form.
- Received 16 December 2011
DOI:https://doi.org/10.1103/PhysRevD.85.084011
© 2012 American Physical Society