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Local Hamiltonian for spherically symmetric gravity coupled to a scalar field
Néstor Alvarez1, Rodolfo Gambini, Jorge Pullin
1Instituto de Física, Facultad de Ciencias, Iguá 4225, esq. Mataojo, Montevideo, Uruguay.
Physical Review Letters
|March 10, 2012
Summary
Researchers developed a new gauge fixing method for gravity with scalar fields in spherical symmetry. This approach allows the Hamiltonian to be a spatial integral of a local density, potentially enabling black hole evaporation quantization.
Area of Science:
- Theoretical physics
- Quantum gravity
- General relativity
Background:
- Formulating gravity coupled with scalar fields in spherical symmetry has been challenging.
- Previous attempts to define a spatially integrated Hamiltonian density for this system were unsuccessful.
Purpose of the Study:
- To present a novel gauge fixing for gravity coupled to a scalar field in spherical symmetry.
- To achieve a Hamiltonian formulation that is a spatial integral of a local density.
Main Methods:
- Introduced a specific gauge fixing procedure for the gravitational and scalar fields.
- Ensured the Hamiltonian is expressed as an integral over space of a local density.
Main Results:
- Successfully formulated the Hamiltonian as a spatial integral of a local density.
- The gauge fixing is applicable to a restricted but potentially significant set of initial data.
Conclusions:
- The developed gauge fixing method offers a new pathway for quantizing gravity in spherical symmetry.
- This formulation could be crucial for studying phenomena like evaporating black holes.
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