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arXiv · 1410.5763

A Note on Black Hole Entropy in Loop Quantum Gravity

S. Carlip
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Abstract

Several recent results have hinted that black hole thermodynamics in loop quantum gravity simplifies if one chooses an imaginary Barbero-Immirzi parameter $\gamma=i$. This suggests a connection with $\mathrm{SL}(2,\mathbb{C})$ or $\mathrm{SL}(2,\mathbb{R})$ conformal field theories at the "boundaries" formed by spin network edges intersecting the horizon. I present a bit of background regarding the relevant conformal field theories, along with some speculations about how they might be used to count black hole states. I show, in particular, that a set of unproven but plausible assumptions can lead to a boundary conformal field theory whose density of states matches the Bekenstein-Hawking entropy.

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S. Carlip. 2014-10-21. A Note on Black Hole Entropy in Loop Quantum Gravity. https://doi.org/10.1088/0264-9381/32/15/155009

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