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Quantum geometry and microscopic black hole entropy

Alejandro Corichi·Jacobo Diaz-Polo·Enrique Fernandez-Borja
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Abstract

Quantum black holes within the loop quantum gravity (LQG) framework are considered. The number of microscopic states that are consistent with a black hole of a given horizon area $A_0$ are counted and the statistical entropy, as a function of the area, is obtained for $A_0$ up to $550 l^2_{\rm Pl}$. The results are consistent with an asymptotic linear relation and a logarithmic correction with a coefficient equal to -1/2. The Barbero-Immirzi parameter that yields the asymptotic linear relation compatible with the Bekenstein-Hawking entropy is shown to coincide with a value close to $γ=0.274$, which has been previously obtained analytically. However, a new and oscillatory functional form for the entropy is found for small, Planck size, black holes that calls for a physical interpretation.

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Alejandro Corichi, Jacobo Diaz-Polo, Enrique Fernandez-Borja. 2006-08-14. Quantum geometry and microscopic black hole entropy. https://doi.org/10.1088/0264-9381%2F24%2F1%2F013

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