TY - JOUR

T1 - Black-hole horizons in modified spacetime structures arising from canonical quantum gravity

AU - Bojowald, Martin

AU - Paily, George M.

AU - Reyes, Juan D.

AU - Tibrewala, Rakesh

PY - 2011/9/21

Y1 - 2011/9/21

N2 - Several properties of canonical quantum gravity modify spacetime structures, sometimes to the degree that no effective line elements exist to describe the geometry. An analysis of solutions, for instance in the context of black holes, then requires new insights. In this paper, standard definitions of horizons in spherical symmetry are first reformulated canonically, and then evaluated for solutions of equations and constraints modified by inverse-triad corrections of loop quantum gravity. When possible, a spacetime analysis is performed which reveals a mass threshold for black holes and small changes to Hawking radiation. For more general conclusions, canonical perturbation theory is developed to second order to include back-reaction from matter. The results shed light on the questions of whether renormalization of Newton's constant or other modifications of horizon conditions should be taken into account in computations of black-hole entropy in loop quantum gravity.

AB - Several properties of canonical quantum gravity modify spacetime structures, sometimes to the degree that no effective line elements exist to describe the geometry. An analysis of solutions, for instance in the context of black holes, then requires new insights. In this paper, standard definitions of horizons in spherical symmetry are first reformulated canonically, and then evaluated for solutions of equations and constraints modified by inverse-triad corrections of loop quantum gravity. When possible, a spacetime analysis is performed which reveals a mass threshold for black holes and small changes to Hawking radiation. For more general conclusions, canonical perturbation theory is developed to second order to include back-reaction from matter. The results shed light on the questions of whether renormalization of Newton's constant or other modifications of horizon conditions should be taken into account in computations of black-hole entropy in loop quantum gravity.

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U2 - 10.1088/0264-9381/28/18/185006

DO - 10.1088/0264-9381/28/18/185006

M3 - Article

AN - SCOPUS:80052982370

SN - 0264-9381

VL - 28

JO - Classical and Quantum Gravity

JF - Classical and Quantum Gravity

IS - 18

M1 - 185006

ER -