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arXiv · 1412.7435

Horizon entropy with loop quantum gravity methods

Daniele Pranzetti·Hanno Sahlmann
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Abstract

We show that the spherically symmetric isolated horizon can be described in terms of an SU(2) connection and a su(2) valued one form, obeying certain constraints. The horizon symplectic structure is precisely the one of 3d gravity in a first order formulation. We quantize the horizon degrees of freedom in the framework of loop quantum gravity, with methods recently developed for 3d gravity with non-vanishing cosmological constant. Bulk excitations ending on the horizon act very similar to particles in 3d gravity. The Bekenstein-Hawking law is recovered in the limit of imaginary Barbero-Immirzi parameter. Alternative methods of quantization are also discussed.

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Daniele Pranzetti, Hanno Sahlmann. 2015-05-18. Horizon entropy with loop quantum gravity methods. https://doi.org/10.1016/j.physletb.2015.04.070

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