Talk detail

Participant	Gambini, Rodolfo
Institution	University of Uruguay Facultad de Ciencias - Igua 4225 esq. Mataojo - Montevideo - Montevideo - Uruguay

Session	QG4	Accepted		Order	Time
Talk	Oral abstract	Title	Quantum scalar field in spherical quantum gravity: Standard and nonstandard techniques.
Co-authors
Abstract	We present a gauge fixing of gravity coupled to a scalar field in spherical symmetry such that the Hamiltonian is an integral over space of a local density. Such a formulation had proved elusive over the years. As in any gauge fixing, it works for a restricted set of initial data. We argue that the set could be large enough to attempt a quantization that could include the important case of an evaporating black hole. We analyse the issue of the initial and boundary conditions. This is a first step towards a full gauge fixed quantization. We aim to compare this approach with gravity coupled to a scalar field in spherical symmetry using loop quantum gravity techniques. Since this model has local degrees of freedom, one has to face ``the problem of dynamics'', that is, diffeomorphism and Hamiltonian constraints that do not form a Lie algebra. We tackle the problem using the ``uniform discretization'' technique. The first model we would like to study with both techniques is the quantum gravitational corrections of the scalar field vacuum in an approximately flat spacetime.