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arXiv · 2012.02700

Super-entropic black hole with Immirzi hair

Simon Boudet·Flavio Bombacigno·Giovanni Montani·Massimiliano Rinaldi
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Abstract

In the context of f(R) generalizations to the Holst action, endowed with a dynamical Immirzi field, we derive an analytic solution describing asymptotically Anti-de Sitter black holes with hyperbolic horizon. These exhibit a scalar hair of the second kind, which ultimately depends on the Immirzi field radial behaviour. In particular, we show how the Immirzi field modifies the usual entropy law associated to the black hole. We also verify that the Immirzi field boils down to a constant value in the asymptotic region, thus restoring the standard Loop Quantum Gravity picture. We finally prove the violation of the reverse isoperimetric inequality, resulting in the super-entropic nature of the black hole, and we discuss in detail the thermodynamic stability of the solution.

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Simon Boudet, Flavio Bombacigno, Giovanni Montani, Massimiliano Rinaldi. 2020-12-04. Super-entropic black hole with Immirzi hair. https://doi.org/10.1103/physrevd.103.084034

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